The many spectacular colors of the Rho Ophiuchi [ http://www.seds.org…] (oh'-fee-yu-kee) clouds highlight the many processes that occur there. The blue regions shine primarily by reflected light. Blue light from the star Rho Ophiuchi [ http://coolcosmos.i…] and nearby stars reflects [ http://antwrp.gsfc.…] more efficiently off this portion of the nebula than red light. The Earth's daytime sky appears blue [ http://www.why-is-t…] for the same reason. The red and yellow regions shine primarily because of emission [ http://antwrp.gsfc.…] from the nebula's atomic and molecular gas. Light from nearby blue stars - more energetic than the bright star Antares [ http://www.astro.ui…] - knocks electrons [ http://www-istp.gsf…] away from the gas, which then shines when the electrons recombine with the gas. The dark regions [ http://antwrp.gsfc.…] are caused by dust grains [ http://nedwww.ipac.…] - born in young stellar atmospheres - which effectively block light emitted behind them. The Rho Ophiuchi star clouds [ http://antwrp.gsfc.…], well in front of the globular cluster [ http://www.seds.org…] M4 [ http://antwrp.gsfc.…] visible above [ http://www.noao.edu…] on far lower left, are even more colorful than humans can see [ http://www.colormat…] - the clouds emits light in every wavelength band [ http://imagine.gsfc…] from the radio [ http://imagers.gsfc…] to the gamma-ray [ http://imagers.gsfc…].
Explanation
The many spectacular colors of the Rho Ophiuchi [ http://www.seds.org…] (oh'-fee-yu-kee) clouds highlight the many processes that occur there. The blue regions shine primarily by reflected light. Blue light from the star Rho Ophiuchi [ http://coolcosmos.i…] and nearby stars reflects [ http://antwrp.gsfc.…] more efficiently off this portion of the nebula than red light. The Earth's daytime sky appears blue [ http://www.why-is-t…] for the same reason. The red and yellow regions shine primarily because of emission [ http://antwrp.gsfc.…] from the nebula's atomic and molecular gas. Light from nearby blue stars - more energetic than the bright star Antares [ http://www.astro.ui…] - knocks electrons [ http://www-istp.gsf…] away from the gas, which then shines when the electrons recombine with the gas. The dark regions [ http://antwrp.gsfc.…] are caused by dust grains [ http://nedwww.ipac.…] - born in young stellar atmospheres - which effectively block light emitted behind them. The Rho Ophiuchi star clouds [ http://antwrp.gsfc.…], well in front of the globular cluster [ http://www.seds.org…] M4 [ http://antwrp.gsfc.…] visible above [ http://www.noao.edu…] on far lower left, are even more colorful than humans can see [ http://www.colormat…] - the clouds emits light in every wavelength band [ http://imagine.gsfc…] from the radio [ http://imagers.gsfc…] to the gamma-ray [ http://imagers.gsfc…].
