(Clearwisdom.net)
(Image from: http://www.ipac.caltech.edu/Science/)
The image above shows part of our Milky Way. This image was retrieved from analyzing IRAS data. The center of the image is the diffused nebula called "NGC 7822." Gas and dust cloud regions are also found in the image. A great number of new stars are forming in this region. These stars are extremely bright, exceeding the sun's brightness by thousands of times.
The image was retrieved from 3 wave bands of infrared observation. The three wave bands are 12, 60, and 100 microns, respectively. The region from yellow to white is the infrared bright region, which will not show up on normal visible-light photos. The newly formed stars are always in the deep region of the gas and dust cloud. However, the gas and dust clouds are nearly completely opaque. The visible light emitted from the newly formed stars is absorbed by the gas and dust clouds. Fortunately, the gas and dust cloud becomes the source of infrared radiation after it absorbs light, and it is heated by the absorbed energy. This allows newly formed stars to be observed in this way.
