Posted on by Evan Gough

What’s Snuffing Out Galaxies Before Their Time?

The VERTICO—Virgo Environment Traced in Carbon Monoxide—Survey observed the gas reservoirs in 51 galaxies in the nearby Virgo Cluster and found that the extreme environment in the cluster was killing galaxies by robbing them of their star-forming fuel. In this composite image, ALMA’s radio wavelength observations of the VERTICO galaxies’ molecular gas disks are magnified by a factor of 20. They are overlaid on the X-ray image of the hot plasma within the Virgo Cluster. Credit: ALMA (ESO/NAOJ/NRAO)/S. Dagnello (NRAO)/Böhringer et al. (ROSAT All-Sky Survey)

In the Milky Way, the formation rate of stars is about one solar mass every year. About 10 billion years ago, it was ten solar masses every year. What happened?

Stars are born in giant molecular clouds (GMCs), and astronomers think that the environment in galaxies affects these clouds and their ability to spawn new stars. Sometimes the environment is so extreme that entire galaxies stop forming new stars.

Astronomers call this “quenching,” and they want to know what causes it.

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Posted on by Tammy Plotner

Messier 89 – the NGC 4552 Spiral Galaxy

Credits: NASA, ESA, STScI, and M. Franx (Universiteit Leiden) and S. Faber (University of California, Santa Cruz)

Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the spiral galaxy known as Messier 89!

During the 18th century, famed French astronomer Charles Messier noticed the presence of several “nebulous objects”  while surveying the night sky. Originally mistaking these objects for comets, he began to catalog them so that others would not make the same mistake. Today, the resulting list (known as the Messier Catalog) includes over 100 objects and is one of the most influential catalogs of Deep Space Objects.

One of these objects is the elliptical galaxy known as Messier 89, which is located about 50 million light years from Earth in the constellation Virgo. This makes it part of the Virgo Cluster, a collection of 2,000 galaxies that lie in the direction of the Virgo and Coma Berenices constellations. This galaxy is not as bright as some other members, which makes it somewhat difficult to spot in small telescopes.

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