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Showing posts with the label astronomy

Camera Obscura

Perhaps it's a little weird for me to begin an article with a glimpse of a romantic movie, but I can't think of a cooler way to start today's topic. When I came up with the idea to write about "Camera Obscura", the first thought that came to my mind was a movie from 1997 called "Addicted to Love". Of all the movies in this genre, only a few are at the top of my mind, and this one, directed by Griffin Dunne with Matthew Broderick and Meg Ryan in lead roles, is definitely the best one I remember. In short, Sam, an astronomer who, in an attempt to win back his girlfriend, turns his astronomical tools into specific spy equipment and, by using his dark-chambered pinhole camera, manages to observe what is happening in the building across the street in real time. What he used to achieve this is a principle behind Camera Obscura—a method to project the light through a small hole and create an image on the opposite wall inside a dark room, tent, or box. Something first observed and described by Mozi, a Chinese philosopher, around 400 years before Christ.


AstroMedia 'The Sun projector' cardboard kit

To better understand what camera obscura really is, think of an eye—a small, almost spherical chamber where light enters via the cornea and through a small pupil, with the iris controlling how much light enters the eye. Light then passes through a lens, which can change its shape to focus the image. The image is projected through a transparent, gel-like substance to the back of the eye (retina and macula), which contains light-sensitive cells. The light travels in straight lines from its source, and because of this, the image is formed flipped and upside down. However, the brain receives the image via the optic nerve and interprets the scene correctly.

Just like in the movie and inside the eye, we could also create our own camera obscura, which in Latin means "dark chamber." Imagine a large room completely darkened by, for example, placing cardboard sheets over the windows with a small, shaped pinhole in the middle of the cardboard. The light from the outside will enter and paint a great image on the opposite wall of the objects from the exterior. Upside down and flipped, but that could be fixed by utilizing a couple of mirrors. Check below in references for the tutorial made by PetaPixel*, an online publication covering the wonderful world of photography, or many other DIY videos from YouTube. There was also a camera obscura exhibit made by Robyn Stacey**, an Australian photographer and visual artist, that turned the Australian city of Brisbane on its head in stunning photographs.


Convert your room into a giant Camera Obscura by PetaPixel*

Today, as a continuation of the small astronomy thread on MPJ, I had my hands on a second AstroMedia kit (of three), and this one was made with the camera obscura principle for observing the Sun, its sunspots, planetary transits, and eclipses. Despite its size, it was surprisingly quick and easy to put together, or more likely, I am becoming much more experienced with paper gluing. :-) Surely, compared to the previously assembled Galilean telescope replica, it was easier to paste more non-round parts than before with the telescope's multiple tubes. Nevertheless, the Sun projector surprised me with its rather large size.

However, the kit is not an ordinary pinhole camera. Instead of a simple aperture of the camera obscura, the solar projector has a lens and two convex mirrors to choose from that work together like a Galilean telescope from the previous post. It is designed to provide higher magnification, and a plane mirror redirects the image to a comfortable viewing position. Best of all, it has a cardboard-made Dobsonian base and can be adjusted to any height between 0° and 90°. Furthermore, on both sides, there are quarter circles with degree scales, which determine the angle between the position of the sun and the horizon, which helps in calculating the height of the sun. With additional apertures, it is possible to reduce the opening and amount of light that enters the box. Smaller apertures can make sharper images. It's a surprisingly comprehensive astronomical tool.


Phases in assembling the Sun projector

To be honest, I was a bit skeptical that all the parts were glued perfectly and aligned for the light to be beaming exactly from the objective lens through the convex mirror to the plane mirror and toward the white screen, but the "First Light", as the astronomers like to call the time of the first observation with brand-new equipment, showed the Sun disc amazingly clear and focused. Now I have to wait for the next eclipse to test it with, which will be in March 2025. Or for the next Mercury transit nine years from now. Unfortunately, the transit of Venus will not happen again in this century. In the meantime, I will definitely play a little more with it and test all its features, including observation of landscapes, as in the summer there is plenty of light, so stay tuned for more information about all it can do.

Unrelated to this project, it reminded me that observing the sun could be very interesting and enjoyable. Once, when I was watching the Sun through the reflecting telescope with a solar filter, a plane transited the Sun disk at the same moment as my observation of one of the previous Mercury transits, and it was so intense, to say the least. Imagine watching Mercury slowly pass through the sun's disk when suddenly the black shadow of an airplane passes the disk in less than a second. I was stunned for a moment, trying to comprehend what exactly happened. I would probably still be puzzled by the event if the airplane hadn't left a contrail behind it, which stayed for a while in the field of view along with small Mercury and a couple of sunspots.


Details from the Sun Projector's "First Light"

Amazingly, Camera Obscura could be dating even back to the past, all the way to the prehistoric settlements. There are theories that prehistoric tribe people witnessed the effect through tiny holes in their tents or in screens of animal hide, which might have inspired them to start with cave paintings. It was not away from logic that they would intentionally make the pinholes in order to monitor the exterior for potential dangers from within their shelters.

Anyhow, it was fun building the kit as well as writing about it. Nature is definitely full of wonders, even with something so simple to test, build, and understand, like it is with monitoring light behavior within a camera obscura. By using the same principle, it is possible to make a small projector that uses a light from a smartphone to project it on the wall, and even the additional mirror is not required if the smartphone is positioned upside down in the first place. We played once with that as well, and the result is in the refs below.

Galilean Telescope (AstroMedia cardboard kit #1)
https://www.mpj.one/2023/07/galilean-telescope.html

What Do Jupiter and Mercury Have in Common?
https://www.mpj.one/2019/11/what-jupiter-and-mercury-have-in-common.html

Transit of Mercury
https://www.youtube.com/watch?v=e2yuXbUdj6o

Shoebox Projector
https://www.youtube.com/watch?v=WAsvUbysEk8

Ref:
 

Galilean Telescope

The knowledge and manufacture of lenses were known since the time of the old Greeks (the word "optics" came from the Greek word ὀπτικά, which means "appearance") and later in the old ages with Egyptian scholar Alhazen, who made important contributions to the study of optics in general. In Europe, the lenses arrived around the 13th century and immediately triggered the invention of the first eyeglasses. However, one important discovery had to wait three centuries later in order to set off a wave of new discoveries in the field of astronomy. The invention was made by Hans Lippershey, the spectacle maker from the Dutch city of Middelburg in the Netherlands, who in October 1608 tried to apply for a patent for a tool he described as an aid capable of "seeing faraway things as though nearby". It consisted of convex and concave lenses in a tube capable of magnifying objects three or four times. For strange reasons, the patent was rejected, but the new instrument immediately attracted attention. Now known as a spyglass, the invention ushered in a new era in astronomy and was the foundation of today's refracting telescopes.


Cardboard replica of the original telescope made by Galileo

Only half a year later, in the early summer, Galileo Galilei at the University of Padua near Venice started to build his first telescope based on the one Hans' made. He managed to design and build telescopes with increasingly higher magnifying power for his own use as well as for presents to his patrons. Galileo was a skilled instrument maker, and his telescopes were known for their high quality. Just like the initial spyglass from the Netherlands, his first telescope was basically a tube containing two lenses, but he managed to enhance the power that magnified objects approximately nine times with his first designs.

Even though Galileo perfected the manufacturing of lenses and telescopes—in later years he managed to produce over a hundred telescopes, some of them with magnifications as high as 33—only two have survived and can be seen in the Museum Galileo (Museo di Storia della Scienza) in Florence. One of the two, especially designed for Cosimo II de' Medici, Grand Duke of Tuscany, with gold-embossed leather, probably had (with initial lenses from the end of 1609) magnification power of around 20. The limiting factor of these early refractors, especially those with higher magnification, was their small field of view, but still, it allowed Galileo to see that the Milky Way is just a multitude of millions of stars and that the Moon's surface was not smooth and perfect but rough, with mountains and craters whose shadows changed with the position of the Sun. He saw the phases of Venus throughout the year and the most interesting fact that planet Jupiter was accompanied by four tiny satellites that moved around it with distinctive proof that not everything in the heavens revolves around the Earth.


Phases in assembling Galileo's historical telescope

This particular gold-embossed leather telescope from the Florence museum was the model for the AstroMedia cardboard replica kit I got my hands on last weekend. It was advertised as "With this historically accurate cardboard replica, you can experience firsthand the great research achievements of Galileo, which he achieved despite the optical performance of this telescope, which is modest by today's standards". All I could say after two days of carefully pasting pieces of paper one after the other was that I couldn't agree more, especially at the last moment when I pointed it to the one-kilometer-away sign of the neighboring shopping center and clearly read what it said. I can only imagine where Galileo pointed his first telescope and what his initial reaction was.

While Galileo did not invent the telescope in the first place, his contribution toward their use in astronomy and science earned him two phrase coins: Galilean telescopes, which now represent a popular name for a refraction telescope type, and Galilean moons, now referring to the first four of Jupiter's natural satellites.


Jupiter's moons as seen through modest reflecting telescope compared to the view
from a small refracting spyglass similar in size to Galileo's original telescope

Unfortunately, I cannot make any astronomy photos with this replica; after all, it is made of cardboard, and fixing it on the moving sky is a mission impossible, not to mention its extremely small field of view, which is perhaps less than a centimeter in apparent terms, which would provide only troubles for focusing the camera through it. For these reasons, I decided to embed a photo of Jupiter's moons as seen with a modest reflecting telescope (the one you can see in the background of the first image above). Below you can find a link to the YouTube video of the entire event we created a couple of years ago when Jupiter was close to Earth. In the upper right corner of the photo, I also included a small view of how Galileo might have seen Jupiter and its four large moons. It is what can be seen with a decent refracting spyglass or powerful binoculars, which, in terms of magnification power, stand at the level of Galileo's scopes.

Camera Obscura (AstroMedia cardboard kit #2)
https://www.mpj.one/2023/07/camera-obscura.html

Jupiter Moons (zviktor22):
https://youtu.be/VTEsXEx-tnE

Ref:
https://astromedia.de/Das-Historische-Galileo-Teleskop
https://catalogue.museogalileo.it/index.html
 

Is Infinity Real?

Sooner or later, computation hardware and artificial intelligence algorithms will inevitably reach the point of enough sophistication that the creation of a simulation of enormous proportions, for example, the size of the entire universe, will be effortless. So to speak. These god-like engineers of such future simulation will indeed face a decision point regarding which degree of limitation to create for their simulated entities or artificial intelligence units in order for them to never reach the point of finding the proof that their world is in fact nothing more than just a series of electrical or optical currents of one inconceivably powerful futuristic computer.

If created right, there's no doubt that the inner world of all those hypothetical units would seem to be as real to them as our own very reality is to us. So, considering the state of obvious, the question arises by itself: if our own reality is such a simulation and we are nothing but AI units within some alien quantum computer, what exactly is the limitation?


To me, it always has been infinity. My own limited mind always struggled with understanding what it really meant. Aristotle, who buzzed his head with infinity quite a lot, concluded that infinity is only potential in nature. We can always add a number to any number to the point of infinity or divide something into infinite parts, but in reality, he thought that it was impossible to exceed every definite magnitude for the simple reason that if it were possible, there would be something bigger than the heavens or something smaller than the atoms (Greek origin: άτομο, which means without volume and uncuttable).

Today we still can't find the proof of bigger or smaller volumes than we can see or understand. If we look up toward the heavens, we are pretty sure that we cannot see beyond the Big Bang or 14 billion light years in all directions due to the limitation of light speed. The same goes with understanding the smaller volumes of microcosm for which we think the current boundary is around the scale of 10e-12 Picometres due to the quantum limitation of observable micro space without disturbance by the observer.


All things considered, as proposed by mathematics, infinity might be just the other word for really, really big, or extremely small, or very old, or too far away. In every way, simply put, infinity might be just beyond our reach. Perhaps if we are really living in the simulation, this is our limitation, and we are pretty much designed in the realm of simulated physics to never reach it and to never learn what is behind the horizon. Ironically, the ultimate truth could be that there was nothing there. It might be where simulation ends and where alien software developers' backdoor is located. Their own reality could be entirely and unimaginably different.

But what if we are not living in a simulation? What if all the laws of physics were not invented by an ingenious developer and were instead real, perfectly natural, and not artificial in origin? Would we have a volume larger than heavens or smaller than quarks and strings? Or just maybe these two extremes are somehow connected and twisted in a loop with no need for infinity at all? Perhaps, ultimately, the size could be irrelevant and not a factor in all cosmic equations.
 
1 +  = ?

http://sten.astronomycafe.net/is-infinity-real/
https://en.wikipedia.org/wiki/Infinity
 

What Jupiter and Mercury Have in Common?

Before we jump to premature conclusions with easy answers such as 'nothing at all' or 'at least they are both orbiting the Sun', perhaps we could do some quick research, just in case... With Jupiter's equatorial radius almost thirty times bigger than the same property on Mercury, the obvious composition difference between one gas giant and a small rocky planet and all the other major differences in mass, density, temperature, orbital inclination, and orbit period, and with almost everything we could compare the two, it is very hard to find the slightest similarity. Not to say that Jupiter in its arsenal is in possession of moons equal to or even bigger in size than the smallest planet of our solar system.


However, within the past couple of seasons, what they had in common was the fact that they were under the spotlight of all of us who, from time to time, enjoy gazing at the sky with our naked eyes or through modest telescopes with a strong feeling of being the witnesses of our own solar system at work. It all started at the end of last year with a rare Jupiter-Mercury conjunction when two planets came close to each other to the size of two moon-diameters. It was easily observed without any optical aids just after the sunset on December 21, 2018.



Even better, the show was on June 12, 2019. On that day, the giant planet was closest to Earth during the celestial event known as Jupiter’s opposition. At its closest point, it came to within 641 million km from Earth. We took the chance to point the telescope and observe the mighty planet and its four largest Galilean moons: IO, EUROPA, GANYMEDE, and CALLISTO. If you watch the video, you'll find the entire story of the event and more facts about the history of the most famous moons, along with short footage from the Sky-Watcher and references in the video's description.



Culmination in our amateur astronomy happened a couple of days ago on November 11, 2019, with the celestial transit of Mercury over the face of the Sun. It was the last transit of the small planet for a while, and the next time it is going to 'eclipse' the mother star again will be in 2032! It was hard to take the photo of the event since it was fuzzy and cloudy with the sunset approaching rapidly, but we made it at last, and it was worth all the efforts.

Stay tuned for more celestial events in the future and maybe some more stories and photos from the active heavens, along with our first long-exposure astrophotographs from outside the solar system.
 

Choosing Planets

Let's turn our imagination to the edge and do something different today. We can call it a thought experiment, a childish game, a daydream, science fiction, pure fantasy, or whatever we want, but let's move the boundaries far away from Earth, far away from our solar system, even farther from our galaxy, and do something wild.

Let's choose a planet.

Or, to be more precise, let's select one in the vastness of the cosmos and move away from this Earth and start new life. Of course, in daydreams we are allowed to do this just because the imagination is what our species differs from others on Earth.

Ok, to begin this little endeavor, we need a little astronomy to start with. What we know for sure is that our galaxy alone contains more than 200 billion stars, the majority of them not so different from our Sun, and by using a basic statistical study based on the planet finder's microlensing technique, there are approximately 100 billion planets orbiting them. Perhaps more. Multiply that by a factor of billions of galaxies in our universe, and you'll get that there are far more Earth twins out there than living people on Earth. There are planets for everybody's taste. So let's start with the planet's basic properties.

Choosing the World

It has to be huge, much bigger than Earth, maybe twice as big in size or even more, to harbor as many people as Earth today and still have plenty of room for many more. To be something like in Canada's distant regions today with only up to a thousand people per square kilometer. However, its composition must be radically different than Earth's, as, in my imagination, it has to maintain gravity more or less like the third rock from the Sun. After all, I don't like to move there and look ridiculously dysfunctional when it comes to, say, simple walking. So fewer heavy elements inside, please, and let it be around the famous, well-known number of 9.81. More or less. So no radical changes when gravity is in question, but I would choose the one with radically fewer water layers than we are familiar with within here. Don't get me wrong, I do like water, and I would like to have plenty of it all over the place, but with no oceans or large seas. Rivers are ok in any variety, lakes too, and small seas are also fine, but please no oceans. Nobody needs that. Hey, it's my planet; if you like oceans, find your own, or don't move anywhere; there are lots of oceans here.

Basically, there must be one giant continent in Norway's style with lots of rivers and lakes and small seas with large bays and calm weather. One rotation cycle could be a little longer than Earth's, but not so much over 30 hours. You can't get rid of old habits that easily. Like Earth, it needs to have a slightly tilted rotation axis to provide longer seasons and temperature changes over the year, with a revolution over the main star similar to the one in Mars or approximately twice as long as Earth's. Earth-like atmosphere and its greenhouse effect would provide a temperature range over the year to be a little milder compared to our native planet, maybe no less than -10°C in harsh winters and no higher than +30°C in summers. A tilted axis and position within the habitable zone of the mother star would also provide no big differences between the planet's equator and pole regions. What else? Oh yes, it has to be protected with both a strong magnetic field and a couple of perfectly positioned giant outer planets from both radiation and looney asteroids and comets. It could also be part of a binary star system, where the second star could also provide additional protection when it comes to violent cataclysmic events in the neighborhood. Last and surely not least, it has to be green all over the place. Extremely suitable for cultivation of various kinds of anything possible. The geography of the planet could be variable with both long valleys and mountains, just like in our home yard.

Humanoids by Star Trek "design"

Do you like my paradise so far? In a way, it was not hard to set the basic astronomical properties of the star system and planet itself. However, a bigger challenge comes with defining the demographics of the planet. You might not like it anymore after I continue and say that I would like the planet to be colonized without any domesticated intelligent species. Why? First of all, it wouldn't be right to find a desirable planet along with at least one dominating intelligent species already evolved there. It would be like colonizing the Americas and killing or putting the population into reservations. We've been there. It's just wrong. Secondly, and probably even more important, is that I would like to share it with other intelligent species. Preferably humanoids. Not mandatory, though. That way neither would be in a position to set a flag and say, "This is mine; everybody else is not looking like me; go away". Basically, in my vision, everyone intelligent who would like to come and build a house is welcome at any time as long as they sign some sort of "sharing" agreement. Something similar to the Antarctic Treaty System we are having here on Earth. Basically, the colonization idea would be comparable to the Earth back in dinosaur time, when all the aliens missed the opportunity to colonize it when no domestic intelligent species existed to claim it for itself. Or they didn't miss it at all, and we are actually them and have never been native to this planet.

So how would all that sharing look like, and what kind of civilization am I talking about? There are so-called Kardashev scales defining possible civilizations out there, dividing them into Types I, II, and III, and it, by definition, represents a method of measuring a civilization's level of technological advancement based on the amount of usable energy they have at their disposal. All three types are far away from the civilization of humans as we know it today, and all three are suitable as potential residents for my planet. By the way, let's call it in further text "M." Accidentally, although I first thought of my first name's initial, it is titled more accurately according to the planet's classification seen in Gene Roddenberry's Star Trek. Anyway, the point of using high-end civilization in my story is that young civilizations like ours are simply not suitable. Why? Several reasons, actually. First, it seems that a big amount of mutual tolerance is needed for the sharing principle I have in mind. All desirable intelligent species have to be evolutionary mature and unburdened by racial, religious, and any other interspecies differences. Additionally, the population must be technologically advanced. The system on the planet would be as simple as possible; there would be no countries nor any kind of political organization, no governments of any kind, nothing like on the third rock of our solar system. There will be just one institution, planetary-based, with just one treaty where all colonists have to sign, and it should be pretty simple. If you want to live there, you would have to choose the land that is free and yet unoccupied, claim it yours, and the only condition to keep it is to produce zero waste outside of its boundaries. Otherwise, you can do whatever you want with it—create your dream house, build a school, trade market, entertainment facility, anything at all—as long as you play fair in relation to others.

ISS 3D Printer and first 'emailed' socket wrench

There will be no cities, as the technology at everybody's disposal would provide transportation to the most distant part of the planet easily, safely, and fast. I see smaller settlements, though, based on their mutual benefits and relations. There will be no sports, at least not in the form of the ones we know on Earth. It would be extremely unfair to play, for example, basketball involving multiple species with different masculine properties. However, the technology sports would survive, like races or any kind of recreational activities. Advanced technology in everybody's home would provide planetary and interplanetary networks of various communications; there would be no need for many supporting factories except for basic ingredients, as home computers would be equipped with state-of-the-art 3D printers capable of producing both simple tools and complex machines. The same home computer would also be able to use food replicators for creating food and food supplements. I don't like the existing concept of killing other species and using them for food. Cultivation and planting are perfectly ok, and each household would possess its own greenhouse for growing appropriate food, but I expect high-end civilizations in evolutionary terms would solve "the meat" problem, and I am not talking about a vegetarian diet.

Of course, the main star system would be well explored, with several outposts built for several purposes, along with mining outer moons, other planets, and asteroids in search of all necessary ingredients for planetary life, along with a variety of orbital activities for planetary residents, including entertainment.

Unfortunately, choosing a world to move is still just a dream. Reality still resides far in the future. Nevertheless, I wonder if such a world already exists out there in a far, far... You know.

Image ref:
https://3dprint.com/32269/made-in-space-emails-wrench/

Refs:
http://hubblesite.org/newscenter/archive/releases/2012/07/full/
http://en.wikipedia.org/wiki/Antarctic_Treaty_System
http://www.nasa.gov/audience/foreducators/k-4/features/F_Measuring_Gravity_With_Grace.html
http://en.wikipedia.org/wiki/Kardashev_scale
http://en.wikipedia.org/wiki/Class_M_planet
http://www.imdb.com/name/nm0734472/
 

Fringe Dream of Virtual Particles

Last night I had a vividly strange science fiction dream. Like with most of my dreams, and dreams in general, I guess, it was hard to recall all the details in the morning, and this one was no exception, but in a nutshell, the scene started with me in some science lab, describing the idea of how to effectively make a tiny hole in the universe. It was pretty simple—I was using four Tesla coils, perfectly positioned in the corners of the large square with edges of about a couple of meters long and with two small, battery-sized metal plates positioned in the center of the square. The experiment was that at the precise moment, Tesla coils fired four filaments of thunder, reaching the center point exactly between two metal plates at the same time, initiating a process that in the end created a tiny breach in the universe that I was describing in the dream as a brane between dimensions and within the void between multiverses. Anyway, in the process, one plate goes from metallic through dark and eventually invisible, while the other started immediately to glow and emit light and other sorts of radiation.


I was explaining in my dream that the breach positioned one plate just outside of our universe while the other stood here. Most of the pairs of virtual particles that were popping between two plates all the time out of vacuum are torn apart by the invisible plate, making them real particles from that point and attracting one toward itself, while the second particle is always attracted by the other plate, creating radiation and the glow in the process. Very similar to the Hawking radiation emitting from the event horizon of the black hole. Even though those two plates were positioned very near to each other, after the Tesla coils did the job by breaching the universe, they stayed in different realms from that point, keeping a relatively close distance between them and finding new equilibrium even when the coils were shut down.

Our plate was then taken out of the square center, wrapped in the bigger case, and used as a battery that never drains. Or, to be precise, not until the invisible plate in the system that is always outside of our universe depletes itself by doing its job of separating the particles, but it was explained in the dream to be an extremely slow process that takes centuries, even if the battery is used to generate lots of power, like empowering entire city blocks.


I know, having a geeky or nerdy dream can be weird for most people, but it's not that we can choose what to dream, can we? It is surely a product of my daydreams, so to speak, and definitely an outcome from my daily interests in astrophysics by watching various documentaries and reading articles online. The novel-like storyline was definitely the consequence of all of my science fiction fascination in both movies and books, which I enjoy from time to time as well. In this very case, the background of the entire story from the last night and today's post is all about the most intriguing feature of the universe. The one that might change everything one day. Virtual particles. They are one of those scientific theories that has extraordinary potential for the future. If we find a way to capture and control them. Hopefully not by poking our universe with bolts of lightning. :-)

But seriously, and sci-fi aside, let's see why virtual particles are one of those quantum properties I think we still wait to understand fully. First of all, they are not really virtual per se; they differ from real particles only by their short existence in time. Aside from that, they can have some or even all properties of the real particles, including mass, but so far it is not really possible to observe virtual particles due to their short lives. However, in the subatomic world, virtual particles are often found in diagrams invented by Richard Feynman that revolutionized theoretical physics by their simplicity to explain what was really happening during the quantum events.


For example, take the Feynman diagram above. It shows how two electrons collide. The internal line is a virtual photon, which is in this case a representation of the excitation of the electromagnetic field caused by electrons and their interaction. We can observe both electrons, their velocities, and paths, but we are helpless to spot the virtual particle. In this very case, whether this virtual photon is really a particle, lasting only a tiny fraction of time during collision, which would give it the title of an actual mediator of the force, just like what its counterpart, the real photon, is, or it is used just as a calculation aid, it is not really certain, but in the end any particle, real or virtual, is only a representation of the excitations of the underlying quantum fields. However, even though they are called "virtual" because of their unobservability, and even though we can't see how they "look" and "act," in one experiment we are definitely able to observe what they do. Experiment proposed by Hendrick Casimir in 1948 and confirmed by Steven Lamoreaux in 1996. The experiment is probably responsible for my dream in the first place. The Casimir effect of the virtual particle-powered machine is just by using two metal plates positioned very near each other. But to understand the Casimir effect, we need to understand one simple thing. Timespace itself. I am not kidding. This is mandatory and a requirement for further reading. Easy. ;-)

Well, I am not pretending that I understand what really happens in the universe, but mainstream science of the current date says, and I am trying to paraphrase it, that all that is around us and within us and at any point in time is just one soup of various fields. Like the Higgs field I talked about once earlier on the blog. Or gravitational field. Or in this post's story and this particular case, electromagnetic field. Any field, by definition, is a region in space (and time?) that is affected by some force. At any point in the field. It also means that a field is a region in space that contains energy. Now, an electromagnetic field is not something that can occupy a certain part of space. It is literally everywhere. It is a fundamental field that is actually in the background of the entire universe and not just in places with matter. Everywhere. Even in the vacuum, where nothing tangible exists. Some places contain more energy than others, with a vacuum being a place with the electromagnetic field in its lowest energy state. Not zero. Now, keep with me; it gets interesting—let's compare this field with actual soup that is always boiling.


If you are looking at the surface of the boiling soup, you will see bubbles and fluid filaments all over the surface, but at some places they are heavier and more powerful, and at other places they are calmer and more peaceful, but always boiling and moving. If we were able to glimpse a closer look and magnify the surface to see it on an even smaller scale, we would see that the entire surface is in a chaotic state of constant wibbling, wabbling, wobbling, blooping, and bubbling*. The same is with electromagnetic fields. The stronger wabbles are what we identify as electromagnetic radiation that propagates forward (and in the case of our soup, outside the pot to the kitchen floor), while the tiny wibbles are just a short-lived emission of photons or failed radiation, if you will.

That tiny failed radiation is possible thanks to quantum mechanics that allows temporary violations of conservation of energy, so one smaller particle can become a pair of heavier particles, and in the case of a photon, it goes from changes of being a wave, a mediator particle with no mass, or a pair of heavier particles—a couple of electrons and positrons (or a pair of quarks and antiquarks with radiation of one gluon). What exactly it is and when it happens is dependent on the ongoing process and energy levels of the system, but in the case of the lowest energy state of vacuum, we know that heavier particles are popping all the time, and due to the uncertainty principle, those virtual particles always appear in pairs. They are borrowing the energy from the vacuum and immediately collide and annihilate themselves, repaying the energy in order not to violate the laws of thermodynamics. These streams of virtual particles "coming out of vacuum and diving back" are well-known quantum features known as quantum fluctuations of the electromagnetic field.


Now, those virtual particles popping out into short existence are coming pretty randomly—and in all possible wavelengths—which brings to "the surface" a vast amount of energy due to their short life, normally invisible to us. If we position two uncharged metal plates very near to each other (less than a micrometer), only those virtual particles whose wavelengths fit a whole number of times into the gap emerge between the plates, while outside, without limitations, all possible wavelengths are accounted for. The result is that energy density between the plates is way less than the energy density of the surrounding space, and immediately a tiny force appears and starts pulling the plates toward each other. This force is named the "Casimir force", and the entire system the "Casimir effect". On first glance, it doesn't look strange—the same effect can be made with two plates in water that, with small waves created by a sonic generator**, are pulling toward each other as well—but keep in mind that the actual Casimir experiment is performed in a vacuum with no single atom of matter between or outside the monitoring system, and the plates are uncharged. So the "only effort" we need to make is to put them very near to each other, and they will start moving. The force is tiny, though; for example, for the one-square-meter plates apart by just one micron, the force is 1.3 mN*** (the weight of 1 kg is about 10N). The force is stronger for bigger plates and with shorter distances in between.

However, one potential propulsion engine, built on the principles of the Casimir effect with even a tiny but constant push like this one, is comparable with ion engines that create thrust by accelerating ions with electricity. For example, in "Dawn", the spacecraft that recently arrived in the asteroid belt was propelled by three xenon-ion thrusters, each with a force of only 90 mN. Eventually, after more than 8 years of travel, it accumulated acceleration over the mission to more than 10 km/s (41,260 km/h), which is pretty fast for a tiny push (even though it used other means of acceleration like gravity boost while transiting Mars). It carried almost 400 kg of xenon for the ion thrust engine, but the potential Casimir engine of the future would need none of such a payload. Its propellant would be the very vacuum of spacetime and its pairs of virtual particles.


Of course, the real application would come with separating virtual particles like in my dream or what black holes seem to do**** on a daily basis. If there is a way to make virtual particles real, the millinewtons will instantly lose that 'milli' prefix and be equipped with one more powerful (perhaps 'kilo' or 'mega'), and that will be something extraordinary. Something that in science fiction has a cool acronym. ZPE. Zero Point Energy. Surely, we must find other means to deal with this than by creating tiny black holes to do the job for us, but thankfully, the quantum world is always full of surprises, and perhaps one day we will build a machine that is capable of taking the energy out of a vacuum safely and is small in size, relatively speaking. Perhaps another quantum effect will be helpful for this job, the one that uses interactions between hydrogen electrons and virtual particles called the Lamb shift. But that is a story for another time.

Image refs:
https://www.nasa.gov/mission_pages/dawn/main/index.html
http://www.livescience.com/50119-superconductors-physicists-gravity-particles.html
http://pics-about-space.com/black-hole-hawking-radiation-diagram?p=3

Refs:
http://math.ucr.edu/home/baez/physics/Quantum/virtual_particles.html
* https://www.youtube.com/watch?v=Kn5PMa5xRq4
https://en.wikipedia.org/wiki/Zero-energy_universe
https://briankoberlein.com/2015/03/06/nothing-but-net/
** https://www.youtube.com/watch?v=PS8Lbq2VYIk
https://www.scientificamerican.com/article/are-virtual-particles-rea/
http://physics.stackexchange.com/questions/147096/are-virtual-particles-tool
***http://math.ucr.edu/home/baez/physics/Quantum/casimir.html
https://en.wikipedia.org/wiki/Virtual_particle
****https://en.wikipedia.org/wiki/Hawking_radiation
 

Solar System Weirdness

Do you know how big our solar system is? I can't be sure, of course, but there's a strong possibility that common knowledge about our planetary neighborhood ends with enumerating most of the planets—one dwarf planet and a couple of named moons, asteroids, and comets. Amazingly, the truth is far, far beyond that, and believe it or not, if we include the Oort cloud, the solar system, with us representing its only living residents, is approximately 3 light-years in diameter. This is, more or less, equal to 3e+13 kilometers, or 30,000,000,000,000 km. The distance is about 100 million times bigger than the distance to the Moon. It is tremendously huge and just about one and a half light-years shorter than the distance from our sun to the nearest star!

The layout of the solar system*

So next time when you, through your polluted sky, look up and see the Moon, Venus, Mars, Jupiter, and occasionally some comet tail or shooting star, remember that what you see is just a fraction of all the weirdness of everything that is gravitationally bonded to the Sun and to each other. So let's see what we don't see with our eyes and check out some weird places, some of them not so far away from our own Earth. And just to be clear, the words 'weird' and 'weirdness' I added in the title and throughout the post are here more for theatrical reasons. Surely, the fact is that what's weird to me and you is only natural behavior and property of the physics of the solar system. We are just trying to understand it.

In such a way, let's start with the first and probably the oldest mystery of the orbiting laws around the Sun. Back then, in the 19th century, French mathematician Urbain Le Verrier tried to study Mercury's orbital motion around the Sun in order to post an orbital model based on Isaac Newton's laws of motion. It happened almost a century before Einstein's theory of relativity, which is a current, state-of-the-art mathematical model of gravity and orbital physics, but back then, Verrier's model simply failed to match the observations. In short, Mercury refused to spot itself on predicted spots on the skies, and in every orbit, its perihelion (or orbital spot where the planet is closest to the sun) moved away from predicted places by a small amount. Unfortunately, instead of doubting the equations, like many times before and after in the history, Verrier posted a theory of a new planet or a large orbital body 'inside' Mercury's orbit that might be responsible for Mercury's misbehavior. He even proposed the name 'Vulcan' because of its potentially very hot orbit so near the Sun. This triggered a series of searches for the Vulcan, and until Einstein came up with the theory of relativity (and its predictions of heavily banded space and time continuum near the heavy objects) that perfectly explained all the observations of one system so close to the massive Sun observed from the distance, many professional and amateur astronomers claimed that they found the Vulcan and spotted its transit over the main star. Perhaps the final dots to the mystery were posted by the SOHO and STEREO solar missions, and neither of them found anything planetoid-ish inside Mercury's orbit. Recent calculations go even further and rule out any asteroid revolving around the Sun inside Mercury's orbit that is bigger than 6 km in diameter.

Lagrange points *2

The next weirdness of the gravitational three-dimensional geometry of the solar system (and all the other star systems out there) is called Lagrange points. Physics was observed and defined by the great Italian mathematician and astronomer Joseph-Louis Lagrange in the 18th century. He identified five points in the orbital system of two massive bodies from the perspective of a third small mass. In short, if we consider, for example, the Sun and Earth, there are three points on the connecting line between the star and the planet (L1, L2, and L3) and two more, L4 and L5, positioned on the top of equilateral triangles where two other vertices are occupied by the Sun and Earth. Now, what is special about these places is that small objects positioned in those points would be able to maintain a stable position relative to the large masses. If you check the image to the left, a small rock positioned at point L1 would be able to revolve around the sun with the same orbital period as the Earth. The same goes with the other four points. However, the first three points are pretty unstable, and objects positioned there would tend to fall out of orbit due to gravitational potential energy shown in the image as well with red and blue arrows. L4 and L5, on the other hand, are completely different stories and very stable, and while a spaceship parked in the first three points would need to fire engines constantly in order to stay put, the same spaceship in L4 and L5 would be able to shut the engines down and park it there for eternity. Think of it like the 'egg vs. equinox' myth: even though you can balance the egg on short or narrow ends (and not just on the equinox), this position is pretty unstable, and even a little vibration would knock the egg out of balance. Similarly, L4/5 points would be like putting the egg in the eggcup. Scientifically speaking, within the Earth-Sun system, L1 is very interesting as the point of monitoring the Sun without any orbital interruptions (SOHO is located there), L2 is a great place for orbital telescopes (Planck and the James Webb Space Telescope), and L3 is pretty useless as it is always hidden by the Sun and therefore the origin of all science fiction stories with a counter-Earth located in that very point, sharing the orbit with us while we would always be unable to see it. Of course, there is no planet on the other side of the sun; otherwise, we would detect its gravitational influence. However, if some aliens exist on the mission of monitoring humankind, they would pretty much choose this place to hide their mothership.

Of course, the solar system is crowded with plenty of large orbiting objects, and Lagrange points, i.e., the Sun-Earth system, are not really points per se, and due to gravitational influences of other planets, they vary in position depending on the current positions of other planets in their orbits. The same goes for the Lagrangian system of Earth-Moon with their L4/5 points, for example, suffering additional complications due to the influence of the Sun. But still, these points are ideal for some futuristic space cities orbiting the Earth, and some 40 years ago, Carolyn Meinel and Keith Henson founded 'The L5 Society' around the idea of Gerard K. O'Neill to build a colony that would be positioned in a tiny orbit around the L5 point in the Earth-Moon system. In addition, there are also plans to use L1 and L2 points in the system to build lunar elevators with appropriate counterweights and 'cables' with the use of materials that already exist in production today since they don't require a lot of strength in the process.

Jupiter and inner-solar system asteroids *3

Lastly, the absolute winner in the weirdness competition of the solar system related to Lagrange points is Jupiter and its L4 and L5 points, or in this case, regions. Due to the nature and stability of the orbits within, Jupiter is using them as a, well, sort of, garbage collector. Believe it or not, these two regions are home to more than 6,000 asteroids. They all travel around the sun with the same speed as their father, Jupiter. By astronomical convention, these asteroids are named after the Trojan War, and therefore the entire regions are called 'Jupiter Trojans'. Surely, the three largest asteroids in there are conveniently named Agamemnon, Achilles, and Hector, and the region around L4 is called the 'Greek camp', while all the others in L5 belong to the 'Trojan camp'. Other planets also collect junk, dust, and small and big asteroids in their L4/5 points, and even Earth owns one (discovered so far). It is a rock 300 meters in diameter orbiting the Sun along with Earth in L4. There are also space rocks detected in Saturn's moons and their L4/5 points, as well as the dust detected in the moons. It will be interesting what we will find in the (far) future when we start exploring the solar system for real. Lagrange points will surely be on the top of all lists to explore, study, and use. I am more than positive that lots of L4 and L5 points throughout the solar system will be used for various space lighthouses, radio beacons, and a wide variety of communication devices. Besides the large number of asteroids caught by Lagrange, there is one more group of 1000+ asteroids gravitationally bonded with Jupiter. Their name is Hildian asteroids, and they are in so-called orbital resonance with the solar system's biggest planet. In this case, it means that Hilda's aphelion point (the farthest distance from the elliptical center) is in resonance with the planet, and on every third orbit it is positioned directly opposite from Jupiter. The story with inner system asteroids doesn't end here, and if we travel a little bit inside the Jupiter orbit from Trojans and Hildas, soon enough we would stumble into a famous asteroid belt with more than a million rocks larger than 1 km in diameter. At the beginning of the 19th century, among certain groups of astronomers, including Heinrich Olbers, the so-called Bode's law stated that each planet in any star system would be approximately twice as far from the star as the one before. Remarkably, it fits nicely in the solar system with the exception of Neptune and the planet between Mars and Jupiter. Bode initiated a search for the planet to confirm the theory, and when, during the years 1801 and 1802, Ceres and Pallas were found in more or less the same orbit, Olbers suggested that they might be remnants of a large planet named Phaeton. The theory flourished in later years, especially after the discovery of other belts's large and small asteroids. Today we know more about asteroids in the belt and their composition and mass (which is around 4% of the mass of the Moon), and the current theory is that Phaeton never existed and that it was more likely that it was never formed due to heavy attraction from nearby giants. Nevertheless, both Vulcan and Phaeton continued to live in the sci-fi realm and also a couple of mythologies.

If we continue our travel toward the outer edges of the system and pass four gas giants, around 30 AU starts another belt full of heavy objects. Actually, astronomers identified two separate subsystems, one named 'Kuiper belt' and the other 'Scattered disc'. Just like the main 'inner' asteroid belt, they contain many rocky objects and dwarf planets, with Pluto as the most famous one, but also objects composed of methane, ammonia, and water ice. The scattered disk can be described as an elongated subset of the Kuiper Belt containing objects with highly eccentric orbits, like short-period comets that orbit the Sun in less than 200 years. The best-known comet from this bucket is no doubt Halley's Comet. The Kuiper Belt was discovered only recently, in the late 20th century, and its discovery owes a big thank you to conspiracy theorists and science fiction writers. Actually, after the last gas giant, Neptune, is found by following the lead of the deviations in Uranus's orbit that were caused by Neptune, the same lead is pursued further, following similar perturbations in Neptune's orbit. This directly led to the discovery of Pluto, but as soon as it was found that its mass wasn't enough, the search continued further, and many were sure that there was another big planet further away, conveniently named Planet X. In the fiction, its name was 'Nibiru', with connections to 'ancient astronauts' theorists who gave it an orbit of 3600 years with a pure doomsday scenario, as once in a while it crosses with Earth's orbit and creates a living hell and pretty much the end of life as we know it. Of course, this was just another nonsense and pseudoscience, but eventually, and most thankfully to astronomer and unofficial father of the 'Kuiper Belt', Mike Brown, who discovered lots of small trans-Neptunian objects beyond Pluto, we today know a great deal about the Kuiper Belt, and in this regard, I will just quote Mike Brown: 'Eris (the biggest TNO along with Pluto so far), and Pluto and all of the rest of them have only a trivial impact on our solar system. You could get rid of any of them (I have a vote which ones, too), and nothing much would change.' Recently, with more precise measurements of Neptune's mass, a new calculation of its orbit accounted for all observed perturbations and deviations. However, this didn't mean Planet X doesn't exist. The new theory just pushed it more beyond toward the edge of the solar system, and it earned a new name. This time it is called Tyche, and its location might be somewhere in the Oort cloud. But before we encounter this final system's weirdness, let's first see what happens just after the Kuiper Belt in the very region where a couple of man-made robots are currently still flying!

Solar system Heliosphere *4

Gravity is, of course, the main property of any star system, but from the 'weird' point of view, our path brings us to the region of the solar system just outside the most eccentric orbit from the swarm of all objects within the scattered disk. And it has nothing to do with rocky objects, tidal forces, or orbital physics. Its name is heliosphere, and it's the first boundary of our system we can positively identify. This is the real edge of the system, where ultimately solar winds finish their travel. Solar wind represents ionized particles emitted by the solar corona, and they start traveling at around four times the speed of sound in the interstellar medium. Geometrically speaking, the heliosphere is actually a bubble around the sun and all the planets and other objects, and it starts from the point where solar winds, due to interaction with solar system particles, slow down to the subsonic speed and end at the point when they fully stop, or more precisely, reach pressure balance with the interstellar medium. What is interesting about the heliosphere bubble is that it is not really spherically shaped. The sun is traveling around the center of the Milky Way, and this bubble follows, forming a comet-like shape with a tail called a heliotail, composed of particles that escaped the heliosphere, slowly evaporating because of charge exchange with interstellar media and particles from other stars. It was also speculated that throughout solar system travel, the front edge might create a turbulence edge, a bow shock, similarly to the meteors or satellites that enter the Earth's atmosphere and burn on top. The bow shock is still not confirmed, and perhaps it doesn't exist, as the sun might not travel with enough speed to form it. But it was observed in the motion of a star system called Mira, a red giant in the constellation Cetus, by GALEX, an orbiting ultraviolet space telescope, in the previous decade. Thanks to both Voyagers, we today know more about the composition and pressure of interstellar gases. Voyager 1 already 'crossed' the heliosphere edge, while Voyager 2 is still inside in the so-called "Heliosheath" region.

However, if solar wind stops at the outer edge of the heliosphere, the sun's gravity goes on and influences much further. The proposed boundary where the sun's gravity weakens and loses its dominance is at about 1.5 light-years from the sun. This edge is also the edge of the theoretical Oort cloud, a spherical disk filled with remnants of the original protoplanetary disc from around the Sun at the time of solar system creation, about 4.6 billion years ago. Due to the large distance, it is suggested that it might contain objects captured from other stars from the time of the 'birth cluster' or the beginning of the solar system and other systems while they were in the process of departing from each other. The Oort cloud, even though not scientifically confirmed today, could start with its inner circle at about 2000 AU or so. One day, when Voyager 1 reaches the region (in about 300 years), it will need another 30000 years to pass it through entirely. Unfortunately, V'Ger will not be operational by then (unless something happens to its power source, like in the first Star Trek movie from 1979). The Oort cloud is so big that its outer circle is not only influenced by the sun's gravity alone but also by the gravity of nearby stars as well as all the influences of the tidal forces of the entire Milky Way.

Imagined view of the Oort cloud *5

In a nutshell, the Oort cloud is one giant swarm of icy objects and the potential source of all long-period comets. It is also suggested that many, if not all, short-period comets originated also from the Oort cloud and were captured by gas giants, especially Jupiter. The story of long-period comets is the one responsible for the new planet X location, or Tyche, I mentioned before. Some 15 years ago, astrophysicists John Matese, Patrick Whitman, and Daniel Whitmire proposed a theory that long-period comets, instead of coming from Oort clouds in random orbits caused by gravitational perturbations originating in galaxy tidal forces, might be fully clustered and notably inclined to orbital planes of planets. As the solution to this clustering or grouping of long-period comets, they proposed the existence of one giant planet inside the Oort cloud that is either similar to Jupiter, only 3-4 times bigger, or even a brown dwarf, a failed star that would count our solar system as a sort of binary star system, which is the most common system in the galaxy. However, this theory, even though the most plausible of all encountered, to add more big planets into our solar system, lacks enough data to spot clusters of long-period comets, as their orbital periods are in the realm of thousands of years. Additionally, within the Wide-field Infrared Survey Explorer space telescope mission and its all-sky infrared survey data, no such dwarf or big planet was found. Even more, WISE ruled out the possibility of a Saturn-sized object at 10,000 AU and a Jupiter-sized or larger object out to 26,000 AU. If it still exists, Tyche might be even further away, which also might mean that it could also harbor large moons of its own. Another bold theory, but more likely, is that it doesn't exist at all, and we just need to learn more about Oort cloud complex physics to understand it fully.

I will be careful while concluding anything substantial out of this post. The fact is that I am not a real scientist or astronomer and definitely not a conspiracy theorist or pseudo-science admirer. To be on the safe side, I can say this: posting new theories in astronomy and cosmology from the surface of Earth is way easier than confirming them. We are talking about a vast region of space, and while astronomical instruments, along with science itself, are more sophisticated and better every year, I have no doubts that the real breakthrough in this realm will come only when we eventually rise up and approach closer 'and see' for ourselves. I also have doubts that this will not happen any time soon, especially not in my or your life span.

Until then, metaphorically speaking, we will continue peeking out of the window and doing math from a distance. And continue to dream about the wonders and weirdness of the heavens, waiting for us to come, see, and finally understand.

Image credits:
* Credit: Charles Carter/Keck Institute for Space Studies
   https://exoplanets.nasa.gov/news/1400/interstellar-crossing-the-cosmic-void/
   http://www.universetoday.com/32522/oort-cloud
*2 http://map.gsfc.nasa.gov/mission/observatory_l2.html
*3 https://en.wikipedia.org/wiki/Jupiter_trojan
*4 http://sci.esa.int/ulysses/42898-the-heliosphere/
*5 http://www.sciencemag.org/mysterious-oort-cloud-objects

Refs:
http://motherboard.vice.com/blog/new-planets
http://www.scientificamerican.com/article/astronomers-skeptical-over-planet-x-claims/
http://www.universetoday.com/89901/pluto-or-eris-which-is-bigger/
http://news.discovery.com/space/alien-life-exoplanets/mike-brown-planetx-pluto.htm
http://voyager.jpl.nasa.gov/where/
http://physics.stackexchange.com/questions/36092/why-are-l4-and-l5-lagrangian-points-stable
http://www.astrosociety.org/edu/publications/tnl/62/equinox2.html
http://www.nss.org/settlement/L5news/L5history.htm
https://en.wikipedia.org/wiki/L5_Society
https://www.nasa.gov/content/nasa-s-ibex-provides-first-view-of-the-solar-system-s-tail
https://en.wikipedia.org/wiki/Michael_E._Brown
 

Science of Life in Solar System

There will come one day in the future. Relatively and astronomically speaking, it might come sooner than we think. It could happen way before we realize that there is no turning back. The day when Mother Earth will simply say, Sorry guys, I have no more energy to sustain this kind of life anymore, and when most of the biodiversity cocoons on Earth will reach the ultimate hazard and start imploding back into themselves. Air and water pollution will help a lot, and not even the planet's regular motions will be able to take us into another interglacial cycle. It is as much inevitable as what we are going to do next. We will take a long look toward the stars and say, "Well, we have to do this sooner or later. It's time to leave the Earth. Time to jump into Christopher Columbus's shoes again. And find the new home."

But we will not get far. There will be no warp drives, "phasers on stun", robots, AIs, or artificial gravity like in sci-fi blockbusters, and there will be no scientific breakthroughs that will bring Moon or Mars gravity to the comfortable number of 1. No, we will be completely helpless in all our efforts to terraform other planets and gas giants' moons. Not at first. Or fast. Or to make large asteroids rotate. Or to initiate Mars' core to fire its lost magnet. Or to make Venus act a little less than hell.


Artificial biodomes of Eden in Cornwall, England*
 

Solar Eclipse

The moon travels around the Earth in an elliptical orbit, and logically there are two points in its path where it is closest and farthest from us. Today it was in "perigee-syzygy" of the Earth-Moon-Sun system, or simply called "supermoon". Coincidentally, it happens that today it has the power to fully block the sunlight in northern Europe and make the biggest shadow one can make on Earth. In Serbia it only made a partial eclipse covering somewhat less than 50% of the solar disk. These are 12 photos I took in intervals of approximately 10 minutes from the eclipse start at 9:40 until it went away around 11:58. The biggest shade was at 10:48. We were pretty lucky today since nature gave us a clear sky with just one stubborn cloud that covered the sun-moon kiss around 11AM.


The above image is the composition of those 12 photos, which I took through our Sky-Watcher telescope with a solar filter. I still don't have a proper camera or adapter for taking astronomical photos, so I used our DSLR and manually took images. Therefore, photos are not ideal and perfect, so I used a little photoshopping to make them as clear as possible.


More about today's event in our neighborhood I found at timeanddate.com and tons of websites, as the media literally went viral this morning. No wonder, as the next partial eclipse in Europe will be in 5 years, and the next total one is not expected before 2026. Unfortunately, a total eclipse in Serbia will not be visible any time soon.


It sure is spectacular when our moon eclipses the sun, but in the celestial sky above, there are more events in the same fashion. I mean, situations when three solar system bodies become aligned, so to speak. In this update of the blog story about the classic eclipse, one of those I took with our scope on May 9, 2016. It was the transit of Mercury across the Sun, and the photo ended very well. I managed to catch one of those giant sunspots as well.
 

Scientific Copenhagen

Do you have that strange feeling when you are about to visit a new city abroad and are a little afraid of what you will stumble upon when it comes to simple things? Like how to use the metro line or how to buy a bus ticket or how to identify your next destination? Or how to book your flight back to your home? Or how to handle a simple dilemma: should you exchange the money to the local currency, or is it wise to put your card in every ATM or any other 'slot' machine on your way?

Hello™ at Microsoft Campus Days, 2014

Ericsson, a Swedish multinational provider of communications technology and services, has the answer for you. And me too. Last week, I took my entire family on the trip to Copenhagen for both business and pleasure hours in the Danish capital. During my previous visits I didn't have much time for tourism or any off-work activity for that matter. So I did a little research this time, and Ericsson's "Networked Society City Index" helped a lot. With the well-developed ICT infrastructure, economy, and social development, as well as environmental progress, Copenhagen is located in the top five within the NSC index, among 31 well-developed worldwide cities. After our visit we left Denmark with a feeling that everything, or most of it, went perfectly smoothly and the applied IT was extremely helpful, simple, and useful. Unified communications (UC), integrated into people's business life from within smart gadgets and laptop computers, were also a big part of it, and I can proudly say that, in a way, I took part in the active development of Rackpeople's* Hello™ for Microsoft® Lync®—UC software that integrates with Microsoft's Lync and Exchange and presents video conferencing within a single click on a wide variety of screens and devices. The business part of last week's Copenhagen trip was to visit Microsoft Campus Days, where Hello™ had a big feature presentation and successfully presented what it can do in the current edition. From the developer's point of view, I have a good feeling that this project will have a long life with plenty of room for more versions in the future, especially if Skype and Lync integrate and create space for non-business users as well.

However, Copenhagen, besides the business side of the medal, has plenty more to offer. History, arts, sport and music events, amusement parks, museums, royal and naval sites, shopping streets and malls, restaurants, walks along the canals, sightseeing from the sea, and many more, but this time we chose to glimpse the city's unique scientific side. With a seven-year-old boy in our small family, along with me being a big fan of science and skeptical of society, our stay was really special. If you add last week's Black Friday hysteria, which brought an enormous smile on my wife's face all day long, I can safely say that we spent one of those memorable times you never forget.

The Rundetårn, a 17th-century astronomical observatory**

The very first day we went to see Rundetårn, an almost 400-year-old observatory built by King Christian IV after the first major success of naked-eye astronomical observation of planetary motion, performed by famous astronomer Tycho Brahe. His incredibly accurate measurement of 6 planets motion at the time was used by Johannes Kepler after Tycho's death in 1601, and for the first time in astronomy, three laws of planetary motion were established, including the one that all planets in the solar system move in elliptical orbits with the Sun at a focus. Even though there are still suspicious thoughts about honest relations between Brahe and Kepler and even uncleared circumstances related to Tycho's death (traces of mercury in hairs from his beard were found in the 1901 autopsy), these two colorful characters of the early 17th century made crucial contributions to our understanding of the universe, including the discovery of Newton's law of gravity, which was a direct outcome of Kepler's laws.

Anyway, the Round Tower in the heart of Copenhagen is still active and one of the oldest functioning astronomy observatories. The dome is 6.75 meters high and 6 meters in diameter and contains a refracting telescope with 80–450x magnification with an equatorial mount. Without an elevator or stairs, walking up and down its unique 209-meter-long spiral ramp that spins 7.5 times is something special I never saw before. Not to mention we had the opportunity to look through the 'scope with two very friendly astronomers who warmly welcomed us and patiently answered all the questions we had.

Apollo 17's moon rock

The next stop in our astronomy tour was the Tycho Brahe Planetarium. It is located not too far away from the observatory and hosts 'The Space Theater' with a 1000-square-meter dome-shaped screen, and seeing a giant 3D Earth rotating in front of you or 30+ meter high mammoths in "Titans of the Ice Age" is the experience you don't want to miss. They also hosted an "A Journey through Space" program and permanent exhibition with meteor specimens and one of the largest moon rocks from the Apollo 17 mission (in the above image).

Science is not science if you don't experiment in the lab, and to have at least a feeling of what scientists do on a daily basis, you have to visit Experimentarium City. The main exhibition last week was "The Brain", with tons of posts waiting to be explored and played with. Needless to say, my favorite was the game with the cool name "Mindball"—in which you have to push the ball only by using brain wave sensors. The more you are relaxed and focused, the more it will get into your control and move in the desired direction.

Mindball—moving the ball with brain activity

If you like to have your brain scanned and to see which part is activated when you move fingers, or if you want to see really cool optical illusions, or to learn more about scientific facts and how stuff works, or to play memory games, or... simply to experience a great family time, visiting Experimentarium City is mandatory.

Finally, no trip to Copenhagen would be allowed to have the adjective 'scientific' in the title without visiting the national aquarium and the zoo. Opened last year, Den Blå Planet, National Aquarium Denmark, located near Copenhagen's airport in Kastrup, is something you would need to see to believe. Especially if you came from a continental country like Serbia. Equally interesting was the zoo, which went viral earlier this year when they decided to euthanize Marius, the young giraffe, because of a duty to avoid inbreeding, approved by the European Breeding Programme for Giraffes. Right or wrong, it is not mine to say, but we humans are responsible for the health of the animal life, and at least it is a good thing that there are scientific organizations that are taking the breeding of animal species seriously. Anyway, perhaps the best impression in both the wild animal and fish exhibitions, to me, was their climate-controlled environments—in the zoo their "Tropical section" with jungle climate conditions, and in the case of the aquarium, it's the "Amazonian region" with tropical plant life, strange-looking fish, and lots of piranhas.

The Little Mermaid

Finally, I want to thank all my coworkers at Rackpeople for having a good time on and off the office, especially Lasse, who invited us for a visit and gave me the opportunity to spend my yearly bonus in Copenhagen. Trips like this are also a great opportunity to learn more about the country and region you are visiting, and I mean not just about the sites, history, monuments, and other attractions, but also about people, hospitality, and friendship. Sometimes, the result is more than you hope for... sometimes less. Perhaps the best advice when you are visiting abroad, no matter if you are doing it as a pure tourist or within a business agenda, or both, is to leave high expectations at home. Nevertheless, Copenhagen is one great corner of the world, more than worthwhile to visit, and this scientific side I wanted to show in this post is something not many cities in the world can offer.

Image references:
Scientific Copenhagen, 2014

References:
* http://www.rackpeople.com/
http://www.ericsson.com/res/docs/2013/ns-city-index-report-2013.pdf
** http://en.wikipedia.org/wiki/Rundetårn
http://www.rundetaarn.dk/en/
http://en.wikipedia.org/wiki/Tycho_Brahe
http://newsfeed.time.com/2012/11/17/was-tycho-brahe-poisoned