Carolyn Collins Petersen, Author at Universe Today

July 24, 2022July 24, 2022 by Carolyn Collins Petersen

Hubble Sees a Mirror Image of the Same Galaxy Thanks to Gravitational Lensing

Gravitational lensing and SGAS J143845+145407

It’s been an amazing couple of weeks for fans of gravitational lensing. JWST grabbed the headlines with a spectacular infrared view of lensing in the SMACS 0723 image, and that had everybody talking. Yet, seeing gravitationally lensed objects is not new. Some can be seen from the ground, and of course, Hubble Space Telescope (HST) has been cranking out views of gravitational lensing for years.

Just a few days ago, HST released another one. It’s a striking view of a distant galaxy called SGAS J143845+145407. It’s the centerpiece of the HST view and appears twice in a mirror image of itself. The galaxy appears a third time, as a very smeared apparition that makes a “bridge” between the other two images.

July 24, 2022July 24, 2022 by Carolyn Collins Petersen

The Deepest Known Canyon in the Solar System, Seen From Space

Solar system worlds beyond Earth have amazing surface features. Thanks to planetary science missions, we see images of canyons, craters, and cliffs across a variety of worlds. Someday, those places will give mountain climbers and hikers new challenges. In particular, Mars will be a favored destination. Future hikers and mountain climbers will be spoiled for choice, even if they must wear space suits to get their thrill on.

For example, there’s the Valles Marineris canyon region. It’s the largest known such feature in the solar system, many times larger than the Grand Canyon here on Earth. The European Space Agency’s Mars Express orbiter just returned breathtaking images of this rift canyon.

July 21, 2022July 22, 2022 by Carolyn Collins Petersen

JWST Sees the Most Distant Galaxy Ever, Just 300 Million Years After the Big Bang

By now, almost everyone has seen the first-release images from JWST and marveled at these amazing views of the infrared universe the telescope was launched to explore. The view of SMACS 0723 seen above illustrates the promise JWST holds. While there are many more early-release images in the observation pipeline, we’re starting to see the first research papers come out. As expected, studies of distant galaxies are grabbing headlines already.

Wow, are these findings amazing! In the last couple of days, websites and social media have been alive with images of a blob that, in reality, is one of the oldest (earliest) galaxies ever seen. It’s one of two—GL-z11 and GL-z13—that show us what they looked like when the Universe was extremely young, about 300 million years after the Big Bang. When confirmed, they’ll mark a milestone in studies of the infant Universe.

July 20, 2022July 20, 2022 by Carolyn Collins Petersen

A Dormant Black Hole has Been Discovered Just Outside the Milky Way

What happens when a massive star dies? Conventional wisdom (and observational evidence) say that it can collapse to form a “stellar-mass” black hole. Astronomers detect black holes by the X-ray emissions they emit.

But, what if the black hole isn’t giving off high levels of X-ray emissions? Then, it could be a very rare object indeed: a dormant black hole. Not many of these have been seen. So, it’s exciting to know that a team of astronomers has found one. It’s called VFTS 243. They detected it in Very Large Telescope observations of stars in the Tarantula Nebula, in the neighboring Large Magellanic Cloud.

July 20, 2022July 20, 2022 by Carolyn Collins Petersen

We Finally Know Where the Highest Energy Cosmic Rays are Coming From: Blazars

Way out there in space is a class of objects called blazars. Think of them as extreme particle accelerators, able to marshall energies a million times stronger than the Large Hadron Collider in Switzerland. It turns out they’re the culprits in one of the great astrophysical mysteries: what creates and propels neutrinos across the universe at blazingly fast speeds? It turns out that the answer’s been there all along: blazars pump out neutrinos and cosmic rays. That’s the conclusion a group of astronomers led by Dr. Sara Buson of Universität Wurzburg in Germany came to as they studied data from a very unique facility here on Earth: the IceCube Neutrino Observatory in Antarctica.

July 14, 2022July 14, 2022 by Carolyn Collins Petersen

A New Instrument is Going to the ISS to Study the Climate Impact of Dust in Earth’s Upper Atmosphere

People often seem surprised when they learn that NASA doesn’t just look out to the other planets, stars, and galaxies. It’s also an agency that studies our own home planet—from space! And why not? Earth is part of the solar system, too. So, to that end, there’s a new Earth studies mission called EMIT on its way to the International Space Station. It’s designed to track dust as it moves from one place to another on our planet through through our atmosphere.

The official name of the mission is the Earth Surface Mineral Dust Source Investigation (EMIT, for short). It will use a high-tech imaging spectrometer to study dust around the globe over the next year.

A dust plume stretches over the eastern Mediterranean, shrouding parts of Greece, Turkey, and Cyprus. The June 2020 image has been cropped and enhanced to improve contrast, and lens artifacts have been removed. NASA’s EMIT mission will help scientists better understand how airborne dust affects climate. Credits: NASA — A dust plume stretches over the eastern Mediterranean, shrouding parts of Greece, Turkey, and Cyprus. The June 2020 image has been cropped and enhanced to improve contrast, and lens artifacts have been removed. NASA’s EMIT mission will help scientists better understand how airborne dust affects climate. Credit: NASA

July 14, 2022July 14, 2022 by Carolyn Collins Petersen

A Star Came too Close to a Black Hole and was Torn Apart. Surprisingly Little Actually Went In

Close-up of star near a supermassive black hole (artist’s impression). Credit: ESA/Hubble, ESO, M. Kornmesser

What happens when a star wanders too close to a supermassive black hole? The obvious story is that it gets sucked in, never to be seen again. Some of its material gets superheated on the way in and that gives off huge amounts of radiation—usually X-rays. That’s not a wrong explanation, just incomplete. There’s more to the story, thanks to a team of astronomers at the University of California at Berkeley. They used a specialized spectrograph at Lick Observatory to study a tidal disruption event. That’s where a star encountered a black hole. What they found was surprising.

July 12, 2022July 12, 2022 by Carolyn Collins Petersen

Dusty Dark Galaxies in the Early Universe Revealed in Various Wavelengths

Artist's impression of a dust-enshrouded starburst (credit: ESO/M. Kornmesser).

Well, this is the week for distant galaxies, isn’t it? Not only has JWST revealed some of the most distant ones ever seen in infrared, but other observatories are studying them, too. Astronomers at the Cosmic Dawn Center in Copenhagen recently discovered several interesting ones in the early Universe. However, they had to get through clouds of dust to do it. Their observations revealed several interesting characteristics of objects that existed when the Universe was only a tenth of its current age.

July 10, 2022July 10, 2022 by Carolyn Collins Petersen

Good News! One JWST Picture Early!

For everybody waiting with bated breath for Tuesday’s release of the first James Webb Space Telescope (JWST) images, NASA’s doing a bit of a tease. They’re releasing one image a day early on Monday afternoon. And, the announcer will be the President of the United States, Mr. Joseph R. Biden. Joining him will be NASA Administrator Bill Nelson, who will conduct this one-of-a-kind White House astronomy briefing. It’s all part of the buildup to the big reveals on Tuesday.

What's JWST going to show us first? There's a sneak preview on Monday. Artist impression of the James Webb Space Telescope. Credit: ESA. — What’s JWST going to show us first? There’s a sneak preview on Monday. Credit: ESA.

July 10, 2022July 10, 2022 by Carolyn Collins Petersen

When did the Sun Blow Away the Solar Nebula?

Young stars have a disk of gas and dust around them called a protoplanetary disk. Credit: NASA/JPL-Caltech

The story of our solar system’s origin is pretty well known. It goes like this: the Sun began as a protostar in its “solar nebula” over 4.5 billion years ago. Over the course of several million years, the planets emerged from this nebula and it dissipated away. Of course, the devil is in the details. For example, exactly how long did the protoplanetary disk that gave birth to the planets last? A recent paper submitted to the Journal of Geophysical Research takes a closer look at the planetary birth crèche. In particular, it shows how the magnetism of meteorites helps tell the story.