Whoo!axel000 wrote:Study - life's building blocks originated from space
More confirmation that life on earth is not unique.
Nice chart.teamonkey wrote:Pluto is still a dwarf planet (as are Eris and Ceres), but it's now also a plutoid (as is Eris).Darkflame wrote:Well, exactly, its completely arbitary.
So whats the point of changing it at all?
Whats the point of expending so much effort on a classification that...from a scientific standpoint...is utterly useless?
It's a bit arbitrary, but the issue is partly down to the planets sweeping up crap. As planets orbit, they affect the dust, gas and rocks in the area. Eventually they sweep it away or collect it. Up until Neptune the solar system is fairly clean, beyond that it gets muckier. Pluto is big enough to clear its orbit, but not big enough to make a significant difference. Hence the classification "trans-Neptunian objects", which now includes plutoids as a specific type.
[EDIT] here:
http://en.wikipedia.org/wiki/Trans-Neptunian_object
"Those red ones in the corner by the fence" still has a use that is specific to one particular garden. It doesn't stop them having a proper name or classification. "Like those red ones in the corner by the fence in our garden" is still useful.Darkflame wrote:But with a one-off sample range we have at the moment, and (very) limited data on stuff around other stars, is it not like defining the names of plants based on where they grow in your back yard :p
If the grow on a yard as opposed to in a garden they're weeds.Darkflame wrote: But with a one-off sample range we have at the moment, and (very) limited data on stuff around other stars, is it not like defining the names of plants based on where they grow in your back yard :p
This image of the Martian soil was taken by the Phoenix Mars Lander's optical microscope and shows the variety of colors, shapes and sizes of the soil particles. Credit: NASA/JPL-Caltech/University of Arizona.
This image taken by the Optical Microscope on NASA's Phoenix Mars Lander on Sol 17 (June 11, 2008) shows soil sprinkled from the lander's Robot Arm scoop onto a substrate that has been micromachined to produce different patterns of pegs and holes to capture the smallest particles in the Martian soil. The micromachined substrates are designed to tightly hold particles for imaging using the Atomic Force Microscope on Phoenix, which should be able to zoom in another 40 times beyond the magnification in this Optical Microscope image. For scale, each strip is 0.4 millimeter (0.016 inch) wide. Credit: NASA/JPL-Caltech/University of Arizona/Imperial College London
SourceThe microscope images show a wide variety of particle sizes, colors and types in the soil. One of the particles viewed through the microscope is just 50 microns across, a little less than diameter of human hair. It is greenish in one part, which Pike says could be olivine, a mineral seen elsewhere on Mars. The other part of the particles "the very characteristic orange color" of the Martian soil as a whole, Pike said.
Another particle is black, glassy and more rounded in its shape. "This may very well be a volcanic glass," Pike said.
The microscope images also showed that the clumpy tendencies of the soil go right down to the microscopic level. The green-and-orange particle is actually "a clump of even finer particles," Pike said.
"It's obviously a very sticky material right down to the finest scale," he added.
Correction: you can only drop lumps of rock on Wales; it was an error made by the website (Bad Astronomy, funnily enough) I found the link on originally.F-ZeroOne wrote:http://down2earth.eu/impact_calculator/
Deepdene Impact.
Drake EquationEuropean astronomers have found a trio of "super-Earths" closely circling a star that astronomers once figured had nothing orbiting it.
The discovery demonstrates that planets keep popping up in unexpected places around the universe.
Scientists are more interested in the broader implications of the finding: The universe is teeming with far more planets than thought.
The mission will extend into the next decade the continuous record of sea-surface height measurements started in 1992 by the NASA-French Space Agency's TOPEX/Poseidon mission and extended by the NASA-French Space Agency Jason 1 mission in 2001.
The satellite will continue monitoring trends in sea-level rise, one of the most important consequences and indicators of global climate change. Measurements from TOPEX/Poseidon and Jason 1 have shown that mean sea level has risen by about three millimeters (0.12 inches) a year since 1993, twice the rate estimated from tide gauges in the past century. But 15 years of data are not sufficient to determine long-term trends.
The Ocean Surface Topography Mission (OSTM)/Jason 2 is a partnership of NASA, the National Oceanic and Atmospheric Administration (NOAA), the French Space Agency Centre National d'Etudes Spatiales (CNES) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).
