Carbon

Oxygen and Carbon Found in Atmosphere of an Extrasolar Planet

The Hubble telescope has identified oxygen and carbon in the atmosphere of an extrasolar planet for the first time. The oxygen and carbon are evaporating from a "hot jupiter" planet HD 209458b, orbiting a star lying 150 light-years from Earth. HD 209458b is only 4.3 million miles from its Sun-like star, completing an orbit in less than 4 days. This is not a sign of life!

Carbonate minerals on Mars

A NASA press release indicates that NASA's Spirit, the first of two Mars Exploration Rovers on the surface within Mars' Gusev crater, has identified carbonate minerals "in the rover's first survey of the site with its infrared sensing instrument, called the miniature thermal emission spectrometer or Mini-TES. Carbonates form in the presence of water, but it's too early to tell whether the amounts detected come from interaction with water vapor in Mars' atmosphere or are evidence of a watery local environment in the past, scientists emphasized."

"We came looking for carbonates. We have them. We're going to chase them," said Dr. Phil Christensen of Arizona State University, Tempe, leader of the Mini-TES team. Previous infrared readings from Mars orbit have revealed a low concentration of carbonates distributed globally. Christensen has interpreted that as the result of dust interaction with atmospheric water. First indications are that the carbonate concentration near Spirit may be higher than the Mars global average.

After the rover drives off its lander platform, infrared measurements it takes as it explores the area may allow scientists to judge whether the water indicated by the nearby carbonates was in the air or in a suspected ancient lake. http://marsrovers.jpl.nasa.gov/gallery/press/spirit/20040109a/graph-carb...

Soot major culprit of global warming?

The observation that soot makes global warming "worse" is well covered today. The BBC covers this - largely because it appears that soot is more important for global warming than realised earlier. Dr James Hansen and Larissa Nazarenko, (Goddard Institute for Space Studies, NASA, and Columbia University Earth Institute) suggest that trying to reduce the amount of soot produced would be easier than cutting carbon dioxide and other greenhouse gas emissions. Concentrations of soot are often high over China and India, where coal and organic fuels are used domestically, and over Europe and North America, where the main source is diesel oil.1

Buckyballs clue to mass extinction 250 million years ago

Earth's most severe mass extinction - an event 250 million years ago that wiped out 90 percent of all marine species and 70 percent of land vertebrates - was triggered by a collision with a comet or asteroid, according to a team led by The University of Washington, Seattle, USA. Evidence is based upon elegant findings involving carbon molecules called buckminsterfullerenes (C60, Buckyballs) with the gases helium and argon trapped inside their cage structures.

The scientists do not know the site of the impact 250 million years ago, when all Earth's land formed a supercontinent called Pangea. However, the space body left a calling card - a much higher level of complex carbon molecules called buckminsterfullerenes, or Buckyballs, with the noble (or chemically nonreactive) gases helium and argon trapped inside their cage structures. Fullerenes, which contain 60 or more carbon atoms and have a structure resembling a soccer ball or a geodesic dome, are named for Buckminster Fuller, who invented the geodesic dome.

The researchers know these particular Buckyballs are extraterrestrial because the noble gases trapped inside have an unusual ratio of isotopes. For instance, terrestrial helium is mostly helium-4 and contains only a small amount of helium-3, while extraterrestrial helium - the kind found in these fullerenes - is mostly helium-3.

"These things form in carbon stars. That's what's exciting about finding fullerenes as a tracer," according to Luann Becker, one of scientific team involved. The extreme temperatures and gas pressures in carbon stars are perhaps the only way extraterrestrial noble gases could be forced inside a fullerene, she said. These gas-laden fullerenes were formed outside the Solar System, and their concentration at the Permian-Triassic boundary means they were delivered by a comet or asteroid.

WebElements: the periodic table on the WWW [http://www.webelements.com/]

Copyright 1993-2011 Mark Winter [The University of Sheffield and WebElements Ltd, UK]. All rights reserved.