সারাংশ

description at other version: The Helix Nebula, which is composed of gaseous shells and disks puffed out by a dying sunlike star, exhibits complex structure on the smallest visible scales. In this image from NASA's Spitzer Space Telescope, infrared light at wavelengths of 3.2, 4.5, and 8.0 microns has been colored blue, green, and red (respectively). The color saturation also has been increased to intensify hues. The "cometary knots" show blue-green heads due to excitation of their molecular material from shocks or ultraviolet radiation. The tails of the cometary knots appear redder due to being shielded from the central star's ultraviolet radiation and wind by the heads of the knots.

Image use policy: http://www.spitzer.caltech.edu/info/18-Image-Use-Policy

লাইসেন্স প্রদান

	এই ফাইলটি পাবলিক ডোমেইনে আছে কারণ এটি শুধুমাত্র নাসা কর্তৃক নির্মিত হয়েছিল। নাসার কপিরাইট নীতি হচ্ছে যে "নাসা কর্তৃক উল্লেখ না থাকলে নাসার উপাদান কপিরাইট দ্বারা সুরক্ষিত নয়"। (Template:PD-USGov, নাসার কপিরাইট নীতির পাতা অথবা জেপিএল চিত্র ব্যবহারের নীতি দেখুন।)
	সতর্কবার্তা: Use of NASA logos, insignia and emblems are restricted per US law 14 CFR 1221. The NASA website hosts a large number of images from the Soviet/Russian space agency, and other non-American space agencies. These are not necessarily in the public domain. Materials based on Hubble Space Telescope data may be copyrighted if they are not explicitly produced by the STScI.[1] See also {{PD-Hubble}} and {{Cc-Hubble}}. The SOHO (ESA & NASA) joint project implies that all materials created by its probe are copyrighted and require permission for commercial non-educational use. [2] Images featured on the Astronomy Picture of the Day (APOD) web site may be copyrighted. [3]