Astronomy Picture of the Day

Discover the cosmos! Each day we feature a different image or photograph of our fascinating universe, along with a brief explanation written by a professional astronomer.

October 25, 1995

Painting with Solar Neutrons
Credit: NASA, CGRO, COMPTEL collaboration.

Explanation: Solar flares are propelled high above the Sun's surface by powerful, twisted magnetic fields. The flares spew high energy atomic and subatomic particles into space. During an intense solar flare on June 15, 1991, a spray of solar neutrons was detected by the COMPTEL instrument onboard NASA's Compton Gamma Ray Observatory. Like paint from a spray can, the neutrons formed the above image (seen in false color) on the COMPTEL detectors. Such astronomical images made by high energy particles are unusual, astronomers typically use visible light and other forms of electromagnetic radiation to study the Universe. High energy particles from solar flares affect the Earth and near Earth environment so solar activity is constantly monitored.

Tomorrow's picture: Aurora Astern

Authors & editors: Robert Nemiroff (GMU) & Jerry Bonnell (USRA).
NASA Technical Rep.: Sherri Calvo. Specific rights apply.
A service of: LHEA at NASA/ GSFC