Friday, November 25, 2011

For now, neutrino calculations holding, 11.25.11

Scientists at Cern have validated some of their calculations regarding neutrinos, tiny particles that they think can travel faster than light. We say that with some uncertainty, though, because as soon as the Opera (Oscillation Project with Emulsion [T]racking Apparatus) collaboration published their findings regarding the particles, physicists started desperately trying to find as many flaws in the experiment as possible.
Why is that? Well, physics, and all the disciplines that rely on it, have many of their baseline calculations and formulas based on the idea that nothing can travel faster than the speed of light. This is especially important to astronomers, because calculating how long light has to travel before we are able to see it from Earth is one of the main ways they figure out approximately how old stars are and how far away they are in space. If all of those calculations are suddenly proved fundamentally flawed, well…everything would have to change. If the findings at Cern are eventually proven true, most of the scientific community will have to undergo a complete overhaul in the way they think and conduct their calculations.
As soon as the earliest results were published in September (with some trepidation—the scientists conducting the experiments are practically begging other facilities around the world to do what they can to try to test the experiments to see what sort of results they get), a laundry list of possible flaws with the experiment has started to form. One of the largest problems has just been tested, and the original results have held.
The idea was that the bunches of neutrinos that are tested would have produced different results based on their string size, or the number of neutrinos that are used at one time during the experiment. To test this, the scientists at Cern ran their experiments at least 20 more times with smaller test sizes, and the original results have still held true. There are still many, many more experiments that need to be conducted to be able to say once and for all that there are some things that can travel faster than light, but for now, one more step has been made in that direction.
 Credit: BBC News Science & Environment.

Friday, November 4, 2011

Scientists re-thinking theories for life on Mars, 11.04.11

New interpretations of data from NASA and European orbiters are beginning to come together, suggesting that the possibility for life on Mars is not so strong on the surface, but much more promising for the subsurface directly underground.

This interpretation comes after researchers have discovered clay and certain types of minerals in the Martian subsurface. Clay can only be formed through the interaction of liquid water with rock, so finding clay under the surface suggests a much more consistent liquid presence than it does for the surface, which usually only has frozen ice in its craters and at its poles.

Image credit:
One of the minerals that they have discovered that supports their new theories is a rather icky-colored stone called prehnite. Prehnite can only form in areas where the temperature is over 400 degrees Fahrenheit, so the presence of prehnite and the abundant clay in the subsurface suggests the likelihood for strong hydrothermal (hot water) activity beneath the Martian surface.

That being the case, it is not so strange to think about the likelihood of finding life on Mars. Based on earth’s own geothermal and hydrothermal activity, scientists know it is possible for various kinds of life (usually bacteria and all manner of simple microbes) to live in their own environments, underground, away from the light of the sun.

So, is it time to chuck the rovers and reach for a shovel instead? Not necessarily. More research still needs to be done. There is also more than enough evidence left on the surface of Mars for astronomers to know there was liquid water there at times, and there is still plenty of ice left in some places, so the possibility for life is still there. The idea of finding bacteria on a planet puts the phrase “finding a needle in a haystack” to shame, though. Knowing where to look that is the hard part.

Credit: NASA.

Telescope solves ancient historical mystery, 10.28.11

Astronomers recently used NASA’s Spitzer Space Telescope to unravel a 2,000 year old mystery. In 185 A.D., Chinese sky watchers made note of something they noticed in the sky. They called it a “guest star” at the time, and continued to make notation of its visibility for about the next 8 months. Astronomers had had ideas about what the object could have been, but now using the power of science, they can peer into the depths of space in the area the Chinese had noted and see what may be left over from this mysterious “guest star.” Their findings? A supernova.
Image credit: NASA/JPL-Caltech/UCLA.
This particular supernova is a Type 1a supernova. Supernovae happen when a star dies, either by imploding in on itself as its core collapses, creating a black hole, or bursting outward, as was the case with this supernova. However, scientists who had observed it before had been puzzled because the debris left over is far larger and more spread out than a supernova of that age should be.

With more observation they discovered the star actually exploded inside of some sort of shell of open space. This allowed the material that was ejected from the star as it exploded to travel unimpeded for great distances, much further than it would have traveled before. At any rate, it is an impressive sight. We can only wonder what the Chinese would have said about their “guest star” all those years ago if they could have seen it up close.

Credit: NASA.