galaxies – Page 3 – Astronomy Now

Hubble captures massive dead disc galaxy

25 June 2017 Astronomy Now

By combining the power of a “natural lens” in space with the capability of NASA’s Hubble Space Telescope, astronomers made a surprising discovery—the first example of a compact yet massive, fast-spinning, disk-shaped galaxy that stopped making stars only a few billion years after the big bang.

Cosmic magnifying-glass effect captures Universe’s brightest galaxies

7 June 2017 Astronomy Now

Boosted by natural magnifying lenses in space, NASA’s Hubble Space Telescope has captured unique close-up views of the Universe’s brightest infrared galaxies, which are as much as 10,000 times more luminous than our Milky Way.

Merging galaxies have enshrouded black holes

10 May 2017 Astronomy Now

Black holes get a bad rap in popular culture for swallowing everything in their environments. In reality, stars, gas and dust can orbit black holes for long periods of time, until a major disruption pushes the material in.

A lot of galaxies need guarding in this Hubble view

8 May 2017 Astronomy Now

Like the quirky characters in the upcoming film Guardians of the Galaxy Vol. 2, NASA’s Hubble Space Telescope has some amazing superpowers, specifically when it comes to observing galaxies across time and space. One stunning example is galaxy cluster Abell 370, which contains a vast assortment of several hundred galaxies tied together by the mutual pull of gravity.

Ancient stardust sheds light on the first stars

9 March 2017 Stephen Clark

Astronomers have used ALMA to detect a huge mass of glowing stardust in a galaxy seen when the Universe was only four percent of its present age. This galaxy was observed shortly after its formation and is the most distant galaxy in which dust has been detected.

Tracing the cosmic web with star-forming galaxies in the distant Universe

3 February 2017 Stephen Clark

A research group led by Hiroshima University has revealed a picture of the increasing fraction of massive star-forming galaxies in the distant universe.

NASA’s Fermi discovers the most extreme blazars yet

31 January 2017 Stephen Clark

NASA’s Fermi Gamma-ray Space Telescope has identified the farthest gamma-ray blazars, a type of galaxy whose intense emissions are powered by supersized black holes. Light from the most distant object began its journey to us when the universe was 1.4 billion years old, or nearly 10 percent of its present age.

Black holes hide in our cosmic backyard

10 January 2017 Stephen Clark

Monster black holes sometimes lurk behind gas and dust, hiding from the gaze of most telescopes. But they give themselves away when material they feed on emits high-energy X-rays that NASA’s NuSTAR mission can detect. That’s how NuSTAR recently identified two gas-enshrouded supermassive black holes, located at the centers of nearby galaxies.

Forming stars in the early universe

21 November 2016 Astronomy Now

The first stars appeared about 100 million years after the Big Bang. When the universe was about 3 billion years old, star formation activity peaked at rates about ten times above current levels. Why this happened, and whether the physical processes back then were different from those today, are among the most pressing questions in astronomy.

Observable universe contains ten times more galaxies than previously thought

13 October 2016 Astronomy Now

Astronomers using data from the NASA/ESA Hubble Space Telescope and other observatories have performed an accurate census of the number of galaxies in the universe. The researchers came to the surprising conclusion that the observable universe contains at least two trillion galaxies. The results also help solve an ancient astronomical paradox — why is the sky dark at night?