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A cratered inferno
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Mercury's surface looks similar to our Moon's. Each is heavily cratered and made of rock. Mercury's diameter is about 4800 km, while the Moon's is slightly less at about 3500 km (compared with about 12,700 km for the Earth). But Mercury is unique in many ways. Mercury is the closest planet to the Sun, orbiting at about 1/3 the radius of the Earth's orbit. As Mercury slowly rotates, its surface temperature varies from an unbearably cold -180 degrees Celsius to an unbearably hot 400 degrees Celsius. The place nearest the Sun in Mercury's orbit changes slightly each orbit - a fact used by Albert Einstein to help verify the correctness of his then newly discovered theory of gravity: General Relativity. The above picture was taken by the only sp ...
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2713 |
savio |
10 years ago |
Rosetta's Comet
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Two days ago, I streamed history being made for the first time ever online, and witnessed the Philae lander's touchdown on Rosetta's comet. The journey took 10 years, 6.4 billion kms away from here, and a 7 hour long landing. Unfortunately, it was an awkward landing where Philae landed approximately 1km away from its intended landing site that currently, one of its 3 legs is not on the surface of the comet and it itself is oriented in a way that no sufficient sunlight is being recieved enough to charge its batteries ever 12 hour rotation. At the moment, plans to try to "hop" the robot back into a position for enough sunlight are being studied, hopefully in time to execute them before Philae dies out sometime between next Friday and Saturday. ...
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6613 |
ehd123 |
9 years ago |
Rosetta's Comet - Update
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Remember Philae? That little lander that was targeting comet Rosetta? https://biology-forums.com/index.php?article=1050It was very big news around two months ago... Sadly, Philae landed incorrectly in a rather awkward position due to technical failings. After all, it was trying to land on the harsh, unstable, deteriorating/burning up surface of a comet. It bounced three times to a site away from the targeted position and ended up in a shady place with insufficient sunlight to recharge its energy reserves. And so it died out after 60 hours of touchdown. Recent tabloids have now reported that Philae is missing! Scientists from the European Space Agency have tried to analyze the images that Philae returned but things just keep on getting more ...
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13011 |
ehd123 |
9 years ago |
We are the stars, we are the universe
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I'd like to share this mind-opening video. Astrophysicist Dr. Neil DeGrasse Tyson was asked by a reader of TIME magazine, "What is the most astounding fact you can share with us about the Universe?" This is his answer. By far, one of the best...
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4506 |
ehd123 |
9 years ago |
Capturing an asteroid
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According to scientists at The Keck Institute for Space Studies in California, NASA is seriously considering capturing an asteroid to put in a high orbit around the moon. If the idea is implemented, we could be looking at a manned mission to "capture" an asteroid in the 2020s. This idea is thought to tie in with the Obama administration's enthusiasm for sending a manned mission to a near-Earth asteroid. If NASA were able to capture an object and lock it into an orbit around the moon, it could be safely used as a practise mission without the need for astronauts to move beyond the range of a rescue mission. ...
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11886 |
duddy |
11 years ago |
The infant stages of of forming a black hole
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This is supernova remnant W49B. It is located about 26,000 light-years from Earth, and as we see it it is approximately 1,000 years old. Compared to other supernova remnants of similar type and age, it is distorted in an usual way. Astronomers believe that it is distorted because it is in the infant stages of of forming a black hole -- the very first time this has been observed.
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4077 |
duddy |
11 years ago |
Asteriod impacts
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The third largest asteroid to ever hit earth has been found in South Australia. According to scientists involved, the asteroid, which measured up to 20 km across, hit Earth approximately 360 million years ago. This was around the time of the Late Devonian mass extinction, strengthening the idea that asteroid impacts have been associated with many mass extinctions throughout the history of life on Earth.
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7303 |
duddy |
11 years ago |
How big is the international space station?
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"The ISS is the largest man made object in space. Here's how it compares to other notable objects, both real and fictional, all drawn to scale."The ISS isn't just the largest space craft ever built, it's also the world's most expensive object. According the Government Accountability Office, it cost upwards of 100 billion dollars to complete.
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3443 |
duddy |
11 years ago |
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3148 |
duddy |
11 years ago |
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3249 |
duddy |
11 years ago |
Dwarf planets
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Not much of a believer in dwarf planets, but here's a cool schematic of some. In 2006 the organization responsible for classifying celestial bodies, the International Astronomical Union, decided that a new class of objects was needed. The solar system's erratic ninth planet, Pluto, was assigned to the new “dwarf planet” category along with four other bodies, all tinier than Earth’s moon. Some astronomers expect there may be as many as 50 dwarf planets in the solar system. Eris, the largest dwarf planet, is only slightly bigger than Pluto, at 1,445 miles in diameter (2,326 km). Discovered in 2003, Eris orbits at an average distance of 68 AU (that is, 68 times the Earth’s distance from the sun) and takes 561.4 Earth years to circle the sun. E ...
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3354 |
duddy |
11 years ago |
Imagine being inside this hurricane
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This fantastic photograph of a hurricane on Saturn was recently snapped by NASA's Cassini spacecraft. It measures an astonishing 2,000 kilometers across the eye - that's big enough to cover the UK twelve times. Wind speeds reach as fast as 150 meters per second.
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3080 |
duddy |
10 years ago |
Simulating Mars in Northern Canada
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A manned mission to Mars will inevitably consist of a few people living in incredibly close quarters in a constantly stressful environment. Starting next summer, Mars Society will be conducting a mock Mars mission in the Canadian Arctic. Six participants will live in a facility 7.6 meters tall (25 feet) and 8.3 meters wide (27 feet). For one full year, they will perform a great deal of geological experiments similar to work that would be done on Mars. Spacesuits will be worn to help simulate Mars-like conditions. Though similar studies have been done in the past, this is the most stressful and will be more true to actual conditions on Mars. The goal of the experiment is to determine leadership structure and what equipment will be necessary. ...
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2867 |
duddy |
10 years ago |
Will the Big Bang be a thing of the past?
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Cosmologists have formulated a new theory that suggest the universe didn’t start with the Big Bang. They believe the birth of the universe happened after a 4D star collapsed into a black hole and ejected debris, which helps explain why the universe has an almost uniform temperature.
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3070 |
duddy |
10 years ago |
Aurora borealis
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This picture of a green and red aurora was taken on September 26, 2013, from the International Space Station. The colours of the aurora borealis depend on which atoms the solar storm excites. Green auroras appear when charged particles from the solar wind crash with oxygen atoms in Earth’s atmosphere and produce green photons; red auroras occur when the particles collide with nitrogen atoms or when there are lower-energy oxygen collisions, producing red photons.
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2583 |
duddy |
10 years ago |