Galaxies that form stars aren't unusual in the universe. However, as astronomers look to more distant corners of the universe, the farther they look back into time. It is believed that the distant universe won't have much star-forming galaxies there. Now astronomers are finding that the distant universe has star-forming galaxies.
Many of the massive galaxies are found much closer to the Milky Way. Many of them are also rich with stars. Going farther out into the universe would mean going back in time as well, and finding star-forming galaxies would be less likely.
Astronomers try to understand more about the universe by also knowing how galaxies are linked with each other. Galaxies mostly tend to form in clusters. There are regions of the universe, though that have lesser galaxies in it. These regions are called voids.
The galaxies are governed by what is known as dark matter. Dark matter isn't directly observed, though astronomers can now of their existence by how objects around it behave. All of these together is known as the cosmic web.
The study of how galaxies and dark matter interact within the cosmic web is done by the Hiroshima group using the Subaru Telescope. The method they use to study the cosmic web is known as weak lensing. Weak lensing is when the foreground galaxies and dark matter act as a gravitational lens in order to view the galaxies that are farther out.
To view the distant galaxies in a clearer way, spectrographs on telescopes are used. In this way astronomers can locate distant galaxies and find out those that are forming stars, according to the Subaru Telescope's site. Dr. Yousuke Utsumi from Hiroshima University and a member of the Hyper Suprime-Cam team is one of those studying the distant universe. Together with him in the study is Dr. Margaret Geller from the Harvard-Smithsonian Center for Astrophysics.
A map of the cosmic web shows that massive star-forming galaxies have been more prominent in the distant universe, as Science Daily reports. As observed by Dr. Utsumi, star-forming galaxies have played an important role in the early universe. He has also said that the study will focus on an interesting time in the universe as well.
The distant universe has much to show about how the early universe was. It shows that the distant universe has star-forming galaxies as well. NASA's Opportunity rover also recently celebrated its 13th year.