Get flash to fully experience Pearltrees
Special Relativity Physics at the end of the nineteenth century found itself in crisis: there were perfectly good theories of mechanics (Newton) and electromagnetism (Maxwell), but they did not seem to agree. Light was known to be an electromagnetic phenomenon, but it did not obey the same laws of mechanics as matter. Experiments by Albert A. Michelson (1852-1931) and others in the 1880s showed that it always traveled with the same velocity, regardless of the speed of its source.
This is pretty much how Kim Stanley Robinson does it in the MARS TRILOGY, although the characters weren't counting on the development of the longevity drugs, which eventually allow some of them to visit Earth again. There is also the issue that long-term colonists to Mars are going to get stuck there anyway, since both the voyage out and any significant time spent on the planet in reduced gravity will make it difficult for them to return to Earth gravity anyway, not without a constant training regime. Children born on Mars will find it even more difficult to adapt to heavier gravity on Earth. Still, we do need to get moving on the colonisation of Mars if we want to set up the tech-foundaries and start churning out Titans for the glory of the God-Emperor. 11/17/10 9:33am
26 May 2011 Last updated at 14:01 ET By Jason Palmer Science and technology reporter, BBC News The study looked at pockets of volcanic material locked in glass An analysis of sediments brought back by the Apollo 17 mission has shown that the Moon's interior holds far more water than previously thought. The analysis, reported in Science , has looked at pockets of volcanic material locked within tiny glass beads. It found 100 times more water in the beads than has been measured before, and suggests that the Moon once held a Caribbean Sea-sized volume of water. The find also casts doubt on aspects of theories of how the Moon first formed.
The universe hates you. Let's get that out of the way right now. The universe loathes your guts and is infuriated by the way you dress, and the stupid way you talk sends it into a murderous rage. It's just one bad morning and an empty coffee canister away from driving to your house and shanking you in the neck. With a supernova.
Seil Collins, reporter (Image: ASA/AEI/ZIB/M.Koppitz and L.Rezzolla) A supercomputer has revealed the process behind the formation of short gamma-ray bursts (GRBs) in gory detail.
Physicists have a new tool to picture how black holes warp the fabric of space-time around them. Just as magnetic field lines show how magnetic forces vary in space, a new study suggests that "tendex" and "vortex" lines show how gravity warps space. The technique offers new insight into why some black holes get a kick after undergoing a merger, and could help in the search for gravitational waves.
Even if predictions of a second sun are fulfilled, the double sunset would not be as spectacular as the one Luke Skywalker witnessed in "Star Wars." YouTube wellers of the fictional "Star Wars" planet Tatooine live under two suns.
LIQUID water may survive on free-floating planets that have no star to warm them. If they also support life, they could act as stepping stones to spread life around the galaxy. Gravitational tussles with other planets or passing stars can eject planets from their solar systems. But even in the cold of space, these wayward worlds could stay warm, thanks to the decay of radioactive elements in their rocky cores. Dorian Abbot and Eric Switzer of the University of Chicago calculate that rocky planets with a similar mass to Earth could remain warm enough to keep water liquid under thick, insulating ice sheets for over a billion years.
Editorial: " Kepler shows us a galaxy fit for life " WHAT are the billions of stars and planets beyond our solar system up to? Do they behave like ours or are we a freak of nature?
Read full article Continue reading page | 1 | 2 | 3 Video: Sun spots SUNSPOTS come and go, but recently they have mostly gone. For centuries, astronomers have recorded when these dark blemishes on the solar surface emerge, only for them to fade away again after a few days, weeks or months.
Video: Magnetic eruption An unusually complex magnetic eruption on the sun has flung a large cloud of electrically charged particles towards Earth. When the cloud hits, which could be anytime now, it could spark aurorae in the skies around the poles and pose a threat to satellites – though probably not a particularly severe one. On 1 August, a small solar flare erupted above sunspot 1092. It would not have raised many eyebrows, except that a large filament of cool gas stretching across the sun's northern hemisphere also chose that moment to explode into space. Despite being separated by hundreds of thousands of kilometres, the two events may be linked.
Update on 5 March: Lead researcher Jack Lissauer says: "Further study of the light curve of this target produced an alternative interpretation wherein one of the co-orbital candidates (KOI 730.03) has a period that is twice what we originally estimated. We think that this new interpretation, without co-orbital candidates, is more likely to be correct. We will continue to acquire Kepler data and ground-based observations ... so we can reach a better understanding of this interesting, multi-resonant, system." Buried in the flood of data from the Kepler telescope is a planetary system unlike any seen before. Two of its apparent planets share the same orbit around their star.
An international team of scientists has discovered a planet made of diamond after first detecting a pulsar using the Parkes and Lovell radio telescopes. Pulsars are essentially small spinning stars approximately 20 km in diameter that emit a beam of radio waves. As the star spins its radio beam sweeps repeatedly over Earth, allowing radio telescopes to pick up a regular pattern of pulses. However, the arrival times of the pulses emanating from the pulsar - known as PSR J1719-1438 - were markedly and systematically modulated. Researchers subsequently concluded the deviation was due to the gravitational pull of a small companion planet orbiting the pulsar in a binary system.
If someone woke me out of a sound sleep and forced me at gunpoint to say which is my favorite camera in the solar system, they’d probably have to shoot me. But I think that HiRISE onboard the Mars Reconnaissance Orbiter would be in the top three. And it’s pictures like this one that put it there: [Click to get to greatly embiggened pictures.] That is not a closeup of my chin before I shave. It’s Mars, a dune field in the far north; at latitude 83.5° to be precise, less than 400 km (240 miles) from the north pole.
There has been a ton of chatter on the interwebs about yet another potentially habitable planet in the Gliese 581 system, approximately 20.5 light years from earth. This one, Gliese 581g, was discovered by the Lick-Carnegie Exoplanet Survey using Keck. Based on its size, is approximately 3 earth masses, with roughly earth-like gravity. More important still, is the fact that it’s roughly in the middle of the “ Goldilocks zone “ Most everyone is focusing on the unfortunate fact that 581g seems to be tidally locked with its sun, which means that one side is blazing hot, and the other is freezing cold (and, of course, that there’d be only either day or night on each side). But who cares?