Carolyn Collins Petersen, Author at Universe Today

July 27, 2023July 27, 2023 by Carolyn Collins Petersen

Astronomers Find a Rare “Einstein Cross”

A great example of an Einstein Cross, as seen by Hubble Space Telescope. A "galaxy" with five nuclei is really one galaxy surrounded by a mirage of four images of a distant quasar. The galaxy lies 400 million light years away; the quasar about 8 billion. Credit: NASA/ESA/Hubble

Gravitational lensing is one of astronomy’s great wonders: a natural lens that magnifies the distant universe. Sometimes a lensing system takes the shape of a so-called “Einstein Cross”. Those are rare and amazingly useful ways to study objects far away in space and time.

July 24, 2023July 24, 2023 by Carolyn Collins Petersen

A New Technique Lets Us Learn What the Milky Way’s Arms Are Made Of

A chemical map of the Milky Way Galaxy superimposed over a NASA Jet Propulsion Laboratory illustration of the Milky Way. Red and blue spots indicate objects with a high or low metallicity, respectively. High metallicity (red) corresponds to the presence of young stars, which are more abundant in spiral arms. Credit: K. Hawkins (UT Austin), NASA/JPL-Caltech/R. Hurt (SSC/Caltech).

We’re all used to seeing maps of the Milky Way rich with stars and nebulae. But, there are regions we can’t see or map using conventional methods. There’s no way to get outside the Galaxy to take pictures of the whole shebang.

July 23, 2023July 23, 2023 by Carolyn Collins Petersen

An Enormous Cosmological Simulation Wraps Up, Recreating Even More of the Universe

In shaping the Universe, gravity builds a vast cobweb-like structure of filaments tying galaxies and clusters of galaxies together along invisible bridges hundreds of millions of light-years long. A galaxy can move into and out of the densest parts of this web throughout its lifetime. Credit: Volker Springel (Max Planck Institute for Astrophysics) et al.

There’s an old joke among astronomy students about a question on the final exam for a cosmology class. It goes like this: “Describe the Universe and give three examples.” Well, a team of researchers in Germany, the U.S., and the UK took a giant leap toward giving at least one accurate example of the Universe.

July 21, 2023July 21, 2023 by Carolyn Collins Petersen

Record-Breaking Magnetar was There in the Data All Along

An artist’s impression of the ultra-long period magnetar—a rare type of star with extremely strong magnetic fields that can produce powerful bursts of energy. Credit: ICRAR

The cosmic zoo has strange beasts that astronomers stumble across in the most fascinating ways. Not long ago a team in Australia found a highly unusual magnetar, one of the weirder denizens of the starry zoo. It’s called GPM J1839-10 and it lies some 15,000 light-years away in the direction of the constellation Scutum.

July 20, 2023July 20, 2023 by Carolyn Collins Petersen

Carbon-Based Molecules Seen Just a Billion Years After the Big Bang

A crop of the JADES Survey field that JWST observed, using its NIRCAM instrument to search for carbon-based molecules.

The more astronomers look at the early Universe, the more discoveries they make. Some of those finds change what they thought they knew about the infancy of the cosmos. For example, the James Webb Space Telescope (JWST) recently found evidence of carbon-based molecules and dust existing only a billion years after the Big Bang. It looks a bit different from the dust observed later in the Universe.

July 13, 2023July 13, 2023 by Carolyn Collins Petersen

Soar Past Thousands of Galaxies in the Early Universe in Thrilling 3D

The Extended Groth Strip that JWST focused on to observe galaxies in the early Universe. The new visualization is a deep dive into this image. Credit: NASA, ESA, M. Davis (University of California, Berkeley), and A. Koekemoer (STScI) — The Extended Groth Strip that JWST focused on to observe galaxies in the early Universe. Credit: NASA, ESA, M. Davis (University of California, Berkeley), and A. Koekemoer (STScI)

Want to visit the most distant galaxy in the early Universe? Now you can via a fantastic visualization created from JWST observations of some of the most distant galaxies ever seen.

July 10, 2023July 10, 2023 by Carolyn Collins Petersen

Want to Find Colliding Black Holes? Check the Disks Around Quasars

This illustration shows the merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. Could black holes like these (which represent those detected by LIGO on Dec. 26, 2015) collide in the dusty disk around a quasar's supermassive black hole explain gravitational waves, too? Credit: LIGO/T. Pyle — This illustration shows the merger of two supermassive black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. Credit: LIGO/T. Pyle

The universe is awash in gravitational waves. The collisions of massive objects such as black holes and neutron stars generate many of them. Now astronomers are wondering about the environments where these catastrophic events occur. It turns out they might need to look at quasars.

July 10, 2023July 11, 2023 by Carolyn Collins Petersen

Ancient Stars Somehow Survived Close to the Center of the Milky Way

The center of the Milky Way as seen from Chile. The core contains very old stars that date back to early in cosmic history. Credit: ESO/P.Horalek CC by 4.0.

The core of our Milky Way Galaxy draws astronomers’ attention like moths to a flame. That’s because there’s a lot going on there. Not only is there a supermassive black hole, but also populations of very ancient red giant stars that swarm the center. Most of them date back at least to the formation of the Galaxy.

July 8, 2023July 8, 2023 by Carolyn Collins Petersen

JWST Sees the Most Distant Active Supermassive Black Hole

A zoomed-in view of images captured by the James Webb Space Telescope in near-infrared light for the Cosmic Evolution Early Release Science (CEERS) Survey. A galaxy assembling itself JWST found in this view has the most distant supermassive black hole seen to date.Credit: NASA, ESA, CSA, Steve Finkelstein (UT Austin), Micaela Bagley (UT Austin), Rebecca Larson (UT Austin). — A zoomed-in view of images captured by the James Webb Space Telescope in near-infrared light for the Cosmic Evolution Early Release Science (CEERS) Survey. A galaxy assembling itself JWST found in this view has the most distant supermassive black hole seen to date. Credit: NASA, ESA, CSA, Steve Finkelstein (UT Austin), Micaela Bagley (UT Austin), Rebecca Larson (UT Austin).

As astronomers push our views of the Universe further back in time, their telescopes keep uncovering surprises. That’s the case with a supermassive black hole in CEERS 1019, a distant very early galaxy.

July 2, 2023July 2, 2023 by Carolyn Collins Petersen

JWST Sees the Beginning of the Cosmic Web

This deep galaxy field from Webb’s NIRCam (Near-Infrared Camera) shows an arrangement of 10 distant galaxies marked by eight white circles in a diagonal, thread-like line. (Two of the circles contain more than one galaxy.) This 3 million light-year-long filament is anchored by a very distant and luminous quasar – a galaxy with an active, supermassive black hole at its core. The quasar, called J0305-3150, appears in the middle of the cluster of three circles on the right side of the image. Its brightness outshines its host galaxy. The 10 marked galaxies existed just 830 million years after the big bang. The team believes the early filament of the Cosmic Web will eventually evolve into a massive cluster of galaxies. Credit: NASA, ESA, CSA, Feige Wang (University of Arizona)

The Cosmic Web is the large-scale structure of the Universe. If you could watch our cosmos unfold from the Big Bang to today, you’d see these filaments (and the voids between them) form throughout time. Now, astronomers using JWST have found ten galaxies that make up a very early version of this structure a mere 830 million years after the Universe began.