|| Home. | Universe Galaxies And Stars Archives. | |
|| Universe | Big Bang | Galaxies | Stars | Solar System | Planets | Hubble Telescope | NASA | Search Engine ||
Young stars in the universe.
This artist's conception shows a young, hypothetical planet around a cool star. A soupy mix of potentially life-forming chemicals can be seen pooling around the base of the jagged rocks. Observations from NASA's Spitzer Space Telescope hint that planets around cool stars -- the so-called M-dwarfs and brown dwarfs that are widespread throughout our galaxy -- might possess a different mix of life-forming, or prebiotic, chemicals than our young Earth.
Life on our planet is thought to have arisen out of a pond-scum-like mix of chemicals. Some of these chemicals are thought to have come from a planet-forming disk of gas and dust that swirled around our young sun. Meteorites carrying the chemicals might have crash-landed on Earth.
Astronomers don't know if these same life-generating processes are taking place around stars that are cooler than our sun, but the Spitzer observations show their disk chemistry is different. Spitzer detected a prebiotic molecule, called hydrogen cyanide, in the disks around yellow stars like our sun, but found none around cooler, less massive, reddish stars. Hydrogen cyanide is a carbon-containing, or organic compound. Five hydrogen cyanide molecules can join up to make adenine -- a chemical element of the DNA molecule found in all living organisms on Earth.
Image credit: NASA/JPL-Caltech.
NASA's Spitzer Space Telescope detected a prebiotic, or potentially life-forming, molecule called hydrogen cyanide (HCN) in the planet-forming disks around yellow stars like our sun, but not in the disks around cooler, reddish stars.
The observations are plotted in this graph, called a spectrum, in which light from the gas in the disks around the stars has been split up into its basic components, or wavelengths. Data from stars like our sun are yellow, and data from cool stars are orange. Light wavelengths are shown on the X-axis, and the relative brightness of disk emission is shown on the Y-axis. The signature of a baseline molecule, called acetylene (C2H2), was seen for both types of stars, but hydrogen cyanide was seen only around stars like our sun.
Hydrogen cyanide is an organic, nitrogen-containing molecule. Five hydrogen cyanide molecules can link up to form adenine, one of the four chemical bases of DNA.
Image credit: NASA/JPL-Caltech/JHU
Universe - Galaxies and Stars: Links and Contacts
|| GNU License | Contact | Copyright | WebMaster | Terms | Disclaimer | Top Of Page. ||