Spiral galaxies, much like our very own Milky Way, are structured like pinwheels of stars, space debris, and planets. Recent findings, however, suggest that these galaxies are much more massive that what was previously speculated. Scientists found out that halos of gas clouds extend outward for more than one million light years. One light-year is equal to six trillion miles.
It was difficult to detect the halos. Scientists were only able to discover the halos using Hubble’s Cosmic Origins Spectograph (COS). They did this by using distant quasars, whirling eyes of super massive black holes, as flashlights to trace ultraviolet lights as it went through the gas holes extensions of the galaxies’ foregrounds. The absorbed light of the gases where further broken down by a spectrograph, to find out the density, temperature, distance, velocity, and chemical make-up of the cloud of gases.
Extending out of the spiral galaxies, the gases provided the galaxies more mass than previously considered. One example, Milky Way, has a diameter of around 100,000 light-years. Furthermore, scientists also discovered huge deposits of gas which is estimated to be millions of degrees Fahrenheit which were encircling the spiral galaxies and halos.
In a news release, study leader and professor of Astrophysics and Space Astronomy at the University of Colorado at Boulder John Stocke reported that gas is stored and later recycled using an extended galaxy halo, going back in the galaxy to refresh a new generation of star formation. In a lot of ways, this is the last piece of the puzzle in the theory of galaxy evolution; this completes the picture in our understanding of how galaxies work.
Astronomers also found out that the enormous gas clouds formed around spiral galaxies have as the same mass as all the stars in their individual galaxies. Also, they discovered that the halos of gases may have considerable consequences on how long the spiral galaxies change in a period of time.
However, scientists would not be able to see the gases soon, as the replacement for the Hubble Space Telescope, the James Webb Space Telescope, will not have UV light gathering capabilities.