Carolyn Collins Petersen, Author at Universe Today

October 5, 2023October 5, 2023 by Carolyn Collins Petersen

A Star Threw Off a Sun’s Worth of Material. And Then it Exploded!

Artist's conception of SN 2023ixf. One of the nearest Type II supernovae in a decade and among the brightest to date, SN 2023ixf is a young supernova. Its progenitor star exploded and the supernova was discovered earlier this year by amateur astronomer K?ichi Itagaki of Yamagata, Japan. Credit: Melissa Weiss/CfA

What happens just before a massive star explodes as a supernova? To figure that out, astronomers need to look at very “young” supernovae across multiple wavelengths of light. That’s what happened when SN 2023ixf occurred in May 2023. It turns out its aging progenitor star blew off a solar mass worth of material just before it died. Now, the big question is: why?

October 2, 2023October 2, 2023 by Carolyn Collins Petersen

New Horizons is Funded Through the Decade. Enough to Explore Another Kuiper Belt Object

Since its last flyby, of the Kuiper Belt object Arrokoth, the New Horizons mission has been exploring objects in the Kuiper Belt as well as performing heliospheric and astrophysical observations. Courtesy: Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute//Roman Tkachenko

The ongoing saga of the New Horizons mission—will it get truncated and its science team disbanded?—may have some resolution. Dr. Nicky Fox, associate administrator of NASA’s Science Mission Directorate at NASA Headquarters announced last Friday that mission operations will continue until at least the end of the decade.

September 19, 2023September 19, 2023 by Carolyn Collins Petersen

The Race to Find the Farthest Galaxy Continues

Scientists with the CEERS Collaboration have identified an object (Maisie’s galaxy) that may be one of the earliest and farthest galaxies ever observed. Credit: NASA/STScI/CEERS/TACC/S. Finkelstein/M. Bagley/Z. Levay.

The very early Universe was a busy place, particularly when stars and galaxies began to form. Astronomers eagerly search for the farthest galaxy—that elusive “first” one to form. JWST is part of that hunt through its Cosmic Evolution Early Release Survey (CEERS).

September 18, 2023September 18, 2023 by Carolyn Collins Petersen

A Collision Between Gigantic Galaxy Clusters. Too Big, Too Early

Hubble Space Telescope image of the El Gordo galaxy cluster. This and other gigantic galaxy clusters are challenging the most common theory of the evolution of structure in the Universe. Credit: NASA, ESA, and J. Jee (University of California, Davis)

Just when cosmologists have a workable theory for when and how galaxy collisions happened in the early Universe, something challenges it. In this case, the challenger is a collision of two massive galaxy clusters that combined to form a gigantic galaxy cluster.

September 17, 2023September 17, 2023 by Carolyn Collins Petersen

A New Technique Confirms the Universe is 69% Dark Energy, 31% Matter (Mostly Dark)

This NASA Hubble Space Telescope image shows the distribution of dark matter in the center of the giant galaxy cluster Abell 1689, containing about 1,000 galaxies and trillions of stars.

How much “stuff” is there in the Universe? You’d think it would be easy to figure out. But, it’s not. Astronomers add up what they can detect, and still find there’s more to the cosmos than they see. So, what’s “out there” and how do they account for it all?

September 16, 2023September 16, 2023 by Carolyn Collins Petersen

If Astronomers See These Chemicals in a Planet’s Atmosphere, There’s Likely an Advanced Civilization There

Artist rendition of a potential water-world exoplanet that might support advanced civilizations. Such life could advertise its existence via technosignatures from industrial or other activities. (Credit: ESA / Hubble / M. Kornmesser) — Artist rendition of a potential water-world exoplanet that might support life. Scientists could determine whether to explore this world based on its planetary entropy production. (Credit: ESA / Hubble / M. Kornmesser)

In an age of ever-growing numbers of exoplanets circling other stars, it’s natural that astronomers search for signatures of advanced civilizations. Such signatures may have biological or technological origins.

September 13, 2023September 13, 2023 by Carolyn Collins Petersen

Quasars Have Always Had Dark Matter Halos

Illustration of an active quasar. What role does its dark matter halo play in activating the quasar? Credit: ESO/M. Kornmesser — Illustration of an active quasar. New research shows that SMBHs eat rapidly enough to trigger them. Credit: ESO/M. Kornmesser

When you look at most galaxies in the Universe, you’re looking at the homes of supermassive black holes. It now appears that quasars, which are active galaxies spitting out huge amounts of radiation from the region around their black holes, also have massive dark matter halos. It turns out they’ve always had them. And, their black hole activity has a direct connection with those halos.

September 12, 2023September 13, 2023 by Carolyn Collins Petersen

Astronomers Observe Blobs of Dark Matter Down to a Scale of 30,000 Light-Years Across

Dark matter fluctuations in the lens system MG J0414+0534. The whitish blue color represents the gravitationally lensed images observed by ALMA. The calculated distribution of dark matter is shown in orange; brighter regions indicate higher concentrations of dark matter and dark orange regions indicate lower concentrations. (Credit: ALMA (ESO/NAOJ/NRAO), K. T. Inoue et al.?

Dark matter remains mysterious and… well… dark. While we don’t yet have a definite idea of what this cosmic “stuff” is made of, astronomers are learning more about its distribution throughout the Universe. Since we can’t see it directly, observers need to use indirect methods to detect it. One way is through gravitational lensing. Another is by looking for emissions from hydrogen gas associated with small-scale dark matter structures in the Universe.

September 7, 2023September 7, 2023 by Carolyn Collins Petersen

Mars Doesn’t Have as Many Minerals as Earth

Even though Mars and Earth had similar early histories, including water, Mars still ended up with fewer minerals than Earth. Why? Image Credit: ESO/M. Kornmesser

Earth and Mars are very much alike, but also very different. Among other things, scientists find that Earth is much more mineral-rich than the Red Planet. It has 6,000 different minerals. By contrast, Mars has only 161. That’s a big difference. How could this have happened?

September 4, 2023September 4, 2023 by Carolyn Collins Petersen

Some Galaxies Contain Double Supermassive Black Holes

A Hubble Space Telescope view of M87's core and its jet. it points nearly directly at us and is also known as a blazar. Astronomers are studying other blazars that have meandering jets and think that binary black holes may be hidden inside some of them. Courtesy STScI.

Blazars occupy an intriguing spot in the cosmic zoo. They’re bright active galactic nuclei (AGN) that blast out cosmic rays, are bright in radio emission, and sport huge jets of material traveling in our direction at nearly the speed of light. For some blazars, their jets look curvy and snaky and astronomers have questions.