Meanings of infrared emission in English

There are unexplained sources of infrared emission, far out among the galaxies.

She only saw them against the craggy polyp because of their infrared emission.

It also had an infrared emission; the dark wrinkled surface was radiating more heat than the little stars were shining on it.

In the 1980s, excess infrared emission was discovered around main-sequence stars; subsequent direct-imaging observations revealed orbiting disks of cold dust to be the source.