Photo's of the Day

 This photo is the many spectacular colors of the Rho Ophiuchi (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 and nearby stars reflects more efficiently off this portion of the nebula than red light. The Earth's daytime sky appears blue for the same reason. The red and yellow regions shine primarily because of emission from the nebula's atomic and molecular gas. Light from nearby blue stars - more energetic than the bright star Antares - knocks electrons away from the gas, which then shines when the electrons recombine with the gas. The dark brown regions are caused by dust grains - born in young stellar atmospheres - which effectively block light emitted behind them. The Rho Ophiuchi star clouds, well in front of the globular cluster M4 visible above on lower left, are even more colorful than humans can see - the clouds emits light in every wavelength band from the radio to the gamma-ray.

 This photo to the left is showing part of Grand Junction, Colorado, being pummeled by a lightning bolt was captured during an extremely active thunderstorm on the night of September 13, 2013. The mighty cloud-to-ground strike illuminated much of the cloud and a shaft of intense rain as well. It appears that the storm was in the building/mature stage, which is when most lightning occurs. Compare this storm’s profile to that of a similar nighttime storm that occurred near Lake Powell, Utah, on September 14, 2013.