Star Formation Archives

September 19, 2023September 19, 2023 by Evan Gough

Galaxies Breathe Gas, and When They Stop, No More Stars Form

Artist concept of how a galaxy might accrete mass from rapid, narrow streams of cold gas. These filaments provide the galaxy with continuous flows of raw material to feed its star-forming at a rather leisurely pace. Credit: ESA–AOES Medialab

For most of the history of astronomy, all we could see were stars. We could see them individually, in clusters, in nebulae, and in fuzzy blobs that we thought were clumps of stars but were actually galaxies. The thing is, most of what’s out there is much harder to see than stars and galaxies. It’s gas.

Now that astronomers can see gas better than ever, we can see how galaxies breathe it in and out. When they stop breathing it, stars stop forming.

September 18, 2023September 18, 2023 by Evan Gough

It’s Like Looking at the Infant Sun: Webb Captures Image of an Energetic Young Star

NASA’s James Webb Space Telescope’s high resolution, near-infrared look at Herbig-Haro 211 reveals exquisite detail of the outflow of a newly forming young star, an infantile analogue of our Sun. Image Credit: ESA/Webb, NASA, CSA, Tom Ray (Dublin)

Ever wondered what our young Sun might have looked like in its infancy some five billion years ago?

The audacious JWST has captured an image of a very young star much like our young Sun, though the star itself is obscured. Instead, we see supersonic jets of gas. Young stars can blast out jets of material as they form, and the jets light up the surrounding gas. The luminous regions created by the jets as they slam into the gas are called Herbig-Haro Objects.

September 6, 2023September 6, 2023 by Evan Gough

JWST Gazes into the Dark Molecular Clouds at the Heart of the Milky Way

The Central Molecular Zone; the Heart of the Milky Way. Image Credit: Henshaw / MPIA

There’s an unusual object near the Milky Way’s heart that astronomers call “The Brick.” It’s a massive cloud of gas called an infrared dark cloud (IDC). The Brick is dense and turbulent like others of its type, but for some reason, it shows few signs of star formation.

Why?

July 28, 2023July 28, 2023 by Carolyn Collins Petersen

JWST Pierces Through a Thick Nebula to Reveal Newly Forming Binary Stars

The NASA/ESA/CSA James Webb Space Telescope has captured a high-resolution image of a tightly bound pair of actively forming binary stars, known as Herbig-Haro 46/47, in near-infrared light. NASA, ESA, CSA, J. DePasquale (STScI), CC BY-SA 3.0 IGO

In 1985, the physicist Heinz Pagels wrote that star birth was a “veiled and secret event.” That’s because the stellar crêches hide the action. But, ever since the advent of infrared astronomy, astronomers have been able to lift that veil. In particular, the Hubble Space Telescope has studied these systems and now, the Webb Telescope (JWST) gives regular detailed views of stellar nurseries.

July 20, 2023July 20, 2023 by Evan Gough

Star Factories Haven’t Changed Much Over the Entire Age of the Universe

“Sh 2-209” is a rare and large-scale star-forming region in the outer region of the Milky Way Galaxy. It's notable for its low metallicity, a characteristic it shares with the early Universe. Image Credit: NAOJ/Subaru Telescope

The ancient Universe is weird and secretive. Scientists have made laudable progress in uncovering more and more information on how the Universe began and what conditions were like all those billions of years ago. Powerful infrared telescopes, especially the ground-breaking James Webb Space Telescope, have let astronomers study the ancient light from the early Universe and remove some of the secrecy.

One of the mysteries astronomers want to untangle concerns star formation. Has it changed much since the Universe’s early days?

June 28, 2023June 28, 2023 by Evan Gough

A Feline in the Heavens: The Smiling Cat Nebula

This is the Smiling Cat Nebula, aka Sh2-284. It's a stellar nursery of ionized hydrogen, powered by young stars in the center. If you can't see the cat, maybe you're more of a dog person. Image Credit: ESO/VPHAS+ team. Acknowledgement: CASU

A stellar nursery sounds like a placid place where baby stars go about their business undisturbed. But, of course, a stellar nursery is nothing like that. (Babies are noisy and cry a lot.) They’re dynamic places where powerful elemental forces rage mightily and bend the surroundings to their will. And this one, even though its name is the drowsy-sounding Smiling Cat Nebula, is no exception.

June 23, 2023June 23, 2023 by Brian Koberlein

Nancy Grace Roman Could Detect Supermassive Dark Stars

Artist view dark neutron star. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

The first stars of the universe were very different than the stars we see today. They were made purely of hydrogen and helium, without heavier elements to help them generate energy in their core. As a result, they were likely hundreds of times more massive than the Sun. But some of the first stars may have been even stranger. In the early universe, dark matter could have been more concentrated than it is now, and it may have powered strange stellar objects known as dark stars.

June 20, 2023June 20, 2023 by Brian Koberlein

An Unfortunate Planet is Undergoing “Extreme Evaporation,” Melting Under the Extreme Heat From its Star

Illustration of a bursting planet about to flare. Credit: Sergei Nayakshin/Vardan Elbakyan, University of Leicester

FU Orionis is an unusual variable star. It was first seen as a magnitude 16 star in the early 1900s, but in the mid-1930s it rapidly brightened to a magnitude 9 star. The rapid brightening of a star was not unheard of, but in this case, FU Orionis did not fade to its original brightness. Since 1937 it has remained around magnitude 9, varying only slightly over time. For decades the mysterious star was thought to be unique, but in the 1970s similar stars were observed, and are now known as FU Orionis objects. Astronomers still had no real idea what could cause such a dramatic change, but a new study argues that it could be caused by a dying young planet.

June 15, 2023June 15, 2023 by Brian Koberlein

More Evidence of Massive First Generation Stars

Artist's rendition of massive, luminous first-generation stars in the Universe. When they died, their supernova explosions produced dust. Credit: NAOC

A few days ago I wrote about the search for Population III stars. These stars were the first stars of the universe. Giant beasts hundreds of times more massive than the Sun, composed only of hydrogen and helium. These massive stars would have been very short-lived, exploding as brilliant supernovae in less than a million years. But Population III stars were so massive, their supernovae were uniquely different from the ones we see today, so our best way to find evidence of them is to look for their supernova remnants. And a recent study published in Nature may have found some.

June 12, 2023June 12, 2023 by Evan Gough

The Tarantula Nebula Shouldn’t Be Forming Stars. What’s Going On?

30 Doradus, also known as the Tarantula Nebula, is a region in the Large Magellanic Cloud. Streamlines show the magnetic field morphology from SOFIA HAWC+ polarization maps. These are superimposed on a composite image captured by the European Southern Observatory’s Very Large Telescope and the Visible and Infrared Survey Telescope for Astronomy. Credit: Background: ESO, M.-R. Cioni/VISTA Magellanic Cloud survey. Acknowledgment: Cambridge Astronomical Survey Unit. Streamlines: NASA/SOFIA

The Tarantula Nebula is a star formation region in the Large Magellanic Cloud (LMC). Tarantula is about 160,000 light-years away and is highly luminous for a non-stellar object. It’s the brightest and largest star formation region in the entire Local Group of galaxies.

But it shouldn’t be.