Interstellar Dust

Hubble telescope measured the quantity of an interstellar dust in the nearest galaxies

Astrophysics learned to estimate quantity of an interstellar dust in galaxies on range of distribution of ultra-violet radiation from the ionized hydrogen. The study was done with information from Hubble telescope. During the research the scientists analyzed structure of 14 galaxies located in relative proximity from Earth. Astrophysics paid the main attention to distribution in radiation of a series of Lyman. This ultra-violet radiation results from hydrogen transition from unexcited condition. Atom transition from the lowest in the basic leads conditions to photon radiation with a length of wave of 121,6 nanometers. This length of a wave is called an alpha as the hydrogen line. Its important property is that such radiation before leaving limits of a galaxy and to reach the Earth is repeatedly reradiated. As a result, round galaxies in a range of the alpha line it is often possible to observe gala, radiated by interstellar gas. In the new work the scientists showed that the sizes of this gala, which sometimes considerably exceeds the sizes of the galaxy, can tell about quantity in it to an interstellar dust. Authors established that the raise dust more, the less distance overcome by radiation of hydrogen. Therefore, knowing the sizes of gala, it is possible to establish the relative contents in a galaxy of an interstellar dust. The Hubble telescope is in an orbit since 1990. It makes observations in the optical and ultra-violet ranges. According to the scientists, with the termination of mission of a telescope and before introduction in a system of the new device of “James Webb” the astrophysics will not have the opportunities to receive images in the ultra-violet range with high resolution, which is now provided by Hubble telescope.
source:NASA

Post navigation