star formation Archives

March 26, 2021March 26, 2021 by Scott Alan Johnston

Newly Forming Stars Don’t Blast Away Material as Previously Believed. So Why Do They Stop Growing?

We thought we understood how stars are formed. It turns out, we don’t. Not completely, anyway. A new study, recently conducted using data from the Hubble Space Telescope, is sending astronomers back to the drawing board to rewrite the accepted model of stellar formation.

February 26, 2021February 26, 2021 by Andy Tomaswick

The Core Of The Milky Way Is An Extreme Place

Astronomers always like to look at incredibly violent places. Violence, in the astronomical sense, makes for rare conditions that can explain much about our universe. One of the violent places that astronomers love to study is the center of our Milky Way galaxy. Now, astronomers from the Center for Astrophysics (CfA) at Harvard have come up with a new catalogue of some of the most intense areas near the galactic core. They hope it will increase our understanding of these potential star-forming regions – and help explain why so few stars are actually formed in them.

February 5, 2021February 5, 2021 by Evan Gough

Astronomers Can Predict When a Galaxy’s Star Formation Ends Based on the Shape and Size of its Disk

An ensemble of twenty-five disk galaxies. The view on the left shows light emitted in the H-alpha line from interstellar gas as a result of ongoing star-formation, while the panels on the right shows the optical light emitted by a mix of young (bluer) and old (redder) stars. Each galaxy can be seen rotated edge-on below its face-on view. Image Credit: TNG Collaboration

A galaxy’s main business is star formation. And when they’re young, like youth everywhere, they keep themselves busy with it. But galaxies age, evolve, and experience a slow-down in their rate of star formation. Eventually, galaxies cease forming new stars altogether, and astronomers call that quenching. They’ve been studying quenching for decades, yet much about it remains a mystery.

A new study based on the IllustrisTNG simulations has found a link between a galaxy’s quenching and its stellar size.

February 1, 2021February 1, 2021 by Paul M. Sutter

Galaxy Mergers can Boost Star Formation, and it can Also Shut it Down

It is known today that merging galaxies play a large role in the evolution of galaxies and the formation of elliptical galaxies in particular. However there are only a few merging systems close enough to be observed in depth. The pair of interacting galaxies picture seen here — known as NGC 3921 — is one of these systems. NGC 3921 — found in the constellation of Ursa Major (The Great Bear) — is an interacting pair of disc galaxies in the late stages of its merger. Observations show that both of the galaxies involved were about the same mass and collided about 700 million years ago. You can see clearly in this image the disturbed morphology, tails and loops characteristic of a post-merger. The clash of galaxies caused a rush of star formation and previous Hubble observations showed over 1000 bright, young star clusters bursting to life at the heart of the galaxy pair.

Galaxy mergers are beautiful sights, but ultimately deadly. In the midst of the collision, the combined galaxy will shine brighter than it ever has before. But that glory comes with a price: all those new stars use up all the available fuel, and star formation grinds to a halt.

January 19, 2021January 19, 2021 by Evan Gough

This is a Simulation of the Interstellar Medium Flowing Like Smoke Throughout the Milky Way

The figure shows a section through the cube of the turbulence simulation. The colors show the density contrast relative to the mean density of the gas. Its turbulent structure is clearly recognizable. Image Credit: Federrath et al, 2021.

How do stars form?

We know they form from massive structures called molecular clouds, which themselves form from the Interstellar Medium (ISM). But how and why do certain types of stars form? Why, in some situations, does a star like our Sun form, versus a red dwarf or a blue giant?

That’s one of the central questions in astronomy. It’s also a very complex one.

January 11, 2021January 11, 2021 by Paul M. Sutter

This is the Fireworks Galaxy. It’s had ten Supernovae in the Last Century Alone

NGC 6946, also known as the Fireworks Galaxy due to the stupendous number of active supernovae. Image credit: ESA/Hubble & NASA, A. Leroy, K.S. Long

Say hello to NGC 6946, otherwise known as the Fireworks Galaxy. This little galaxy is the most prolific producer of supernovae in the known universe, popping off those incredible explosions roughly once a decade. It’s secret? An incredibly high rate of star formation.

November 8, 2020November 8, 2020 by Paul M. Sutter

Massive stars get kicked out of clusters

A "super star cluster", Westerlund 1, which is about 16,000 light-years from Earth. It can be found in the southern constellation of Ara. The picture was taken from the European Southern Observatory's VLT Survey Telescope. Credit: ESO/VPHAS+ Survey/N. Wright

The largest stars in the universe tend to be loners, and new research points to the reason why. Although massive stars are born in clusters of many smaller brethren, they quickly get kicked out, forced to spend their lives alone.

August 12, 2020August 9, 2020 by Paul M. Sutter

Seeing baby stars at every stage of their formation

Observations of the Taurus Molecular Cloud obtained by the Herschel Space Observatory. Image credit: ALMA (ESO/NAOJ/NRAO), Tokuda et al., ESA/Herschel

Stars form from the collapse of dense clouds of gas and dust, which makes it very hard for astronomers to watch the process unfold. Recently the ALMA telescope has revealed a treasure trove of embryonic stars in the Taurus Molecular Cloud, illuminating how baby stars are born.

July 7, 2020July 7, 2020 by Evan Gough

The Corona Australis Molecular Cloud. Normally this Looks Like a Dark Blob in the Sky. But in Infrared, it Looks Like This.

A composite image of the Corona Australis molecular cloud from the ESA's Herschel and Planck Space Observatories. Image Credit: ESA/Herschel/Planck; J. D. Soler, MPIA

The Corona Australis is a constellation in the southern hemisphere. It’s name literally means “southern crown.” One of its features is the Corona Australis molecular cloud, home to a star-forming region containing young stars and proto-stars. It’s one of the closest star-forming regions to us, only about 430 light years away.

The ESA has given us a new composite image of the cloud with data from the Herschel Space Observatory and the Planck Space Observatory.

June 5, 2020June 5, 2020 by Nancy Atkinson

Hubble Looked as Far Back in Time as it Could, and Still Couldn’t See the First Generation of Stars in the Universe

New results from the NASA/ESA Hubble Space Telescope suggest the formation of the first stars and galaxies in the early Universe took place sooner than previously thought. A European team of astronomers have found no evidence of the first generation of stars, known as Population III stars, when the Universe was less than one billion years old. This artist’s impression presents the early Universe. Image Credit: ESA/Hubble, M. Kornmesser.

Astronomers don’t know exactly when the first stars formed in the Universe because they haven’t been observed yet. And now, new observations from the Hubble Space Telescope suggest the first stars and galaxies may have formed even earlier than previously estimated.

Why? We *still* haven’t seen them, even with the best telescope we’ve got, pushed to its limits.