MPJ

Do you know how big is our Solar system? 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 couple of named moons, asteroids and comets. Amazingly, the truth is far, far beyond that and believe it or not, if we include 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 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*

Until recently I had a toy-model of Russian space station Mir hanged in our living room settled nicely between two more common house decorations. It was small in size, no bigger than five cubic inches with two teeny tiny Soyuz spacecrafts docked at their designated locks and numerous solar panels all over the place. The plastic toy is long gone now but still from time to time it raises some nice memories, especially those moments when couple of our guests after close inspection from all directions asked questions like "What the heck is this?" or "Is this art?". Not many of them recognized the most challenging technological endeavor of the last two decades of previous century at first glance. On March 23, 2001, all the biggest Mir's fragments after surviving hellish re-entry through the atmosphere hit the Pacific ocean and ended 15 years of various scientific experiments performed by 28 long duration multinational crews with total of 104 people from 12 ...

Just like a single ant who's lost in the large expanse of Brazilian Casino Beach ( Praia do Cassino , 250km in length, considered to be the largest beach on Earth), and felt as small as possible in surrounding space, we humans are experiencing similar sensation when it comes to space and especially time. But, contrary to ants, we have the ultimate tool, called science, that is allowing us to see beyond the horizon. If we could place ourselves in ant's shoes, we would find clues and evidence all around us and, metaphorically speaking, no matter of large quantities of sand grains, we would know that we were on the beach. And with time, when it comes to history of life, all the clues lie in fossil records of coral reefs. The main study, performed by J.E.N. Veron in his publication " A Reef in Time ", identified five periods in Earth's history with major extinction of corals that built reefs. In all five periods, fossil records of the reefs needed millions of ...

Moon travels around the Earth in 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 made the biggest shadow one can do on Earth. In Serbia it only made partial eclipse covering somewhat less than 50% of the Solar disk. These are 12 photos I took in intervals of approximately 10 minutes from 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 the nature gave us clear sky with just one stubborn cloud that covered the Sun-Moon kiss around 11AM. Above image is the composition of those 12 photos which I took through our Sky-Watcher telescope with solar filter. I still don't have proper camera or adapter for taking astronomical photos so I used ...

Do you know what is one significant difference between Uranus and all the other planets in Solar system? Unlike the other seven planets who, more or less, rotate in "normal" up-down position (or down-up in case of Venus), Uranus is quite abnormal. It's north-south pole rotational axis lies almost in ecliptic because it is tilted by 97.8 degrees and rotates in almost vertical direction toward the orbiting plane. In simple words, Uranus is one giant rolling ball where if you are located on its pole, you would be experiencing only one day and one night during 84 years long orbit while if you are settled near the equator, thanks to ultra-fast rotation time (for a giant planet) of 17 hours you would be experiencing fast switching between day and night and during both solstices the Sun would always be on the horizon. Thanks to this strange position of Uranus axis (probably due to some cosmic collision happened in early Solar system), the weather and climate on Uranus are always...

In the last post of the Beth's Q&A we tried to understand four basic forces and their corresponding particle carriers or bosons. With almost certain discovery of the Higgs boson physicist completed the search for this last mystery of the standard model and we now know how larger particles get their mass and how interact with each other. Now is the time to bring this story up one level and write about chemical elements representing basic 'lego' blocks of almost everything in the universe we currently comprehend. Hmm, everything but mysterious dark matter that we still don't have a clue what it's made of. Every now and again in media (mostly internet) we can read about how we all are made out of stars and other violent events in the universe dating back in time even so far in the past to the Big Bang itself. Following some of this articles Beth posted another idea for the thread and I am paraphrasing her thoughts: "I keep reading we are made from the ...