Carolyn Collins Petersen, Author at Universe Today

February 24, 2023February 24, 2023 by Carolyn Collins Petersen

Recreating the Extreme Forces of an Asteroid Impact in the Lab

Barringer Meteor Crater in Arizona. Scientists studied the forces in the event that created this impact scar. Image credit: NASA

About 50,000 years ago, a nickel-iron meteorite some 50 meters across plowed into the Pleistocene-era grasslands of what is now Northern Arizona. It was traveling fast—about 13 kilometers per second. In just a few seconds, an impact dug out a crater just over a kilometer wide and spread rocks from the site for miles around.

February 23, 2023February 23, 2023 by Carolyn Collins Petersen

Supermassive Black Holes on a Collision Course

Artist's impression of two merging black holes. Credit: Bohn, Throwe, Hébert, Henriksson, Bunandar, Taylor, Scheel/SXS

The early Universe was swimming with dwarf galaxies only a few hundred million years after the Big Bang. They merged with each other over time, building larger and more massive galaxies. At the same time, the giant black holes inside these dwarfs merged, too.

February 22, 2023February 22, 2023 by Carolyn Collins Petersen

Astronomers Find a Group of Water-rich Asteroids

Artist's conception of a solar system in formation. It's likely that exoplanet formation around other stars proceeded similarly. Credit: NASA/FUSE/Lynette Cook

If you’ve ever been at sea or visited a seacoast, you probably looked out at the vast expanse of ocean and wondered, “How did all this water get here?” The answer goes back to Earth’s origins some 4.5 billion years ago. In those early times, water-rich planetesimals and other bodies transported water to our still-growing planet. A recent discovery of a previously unknown population of such asteroids between Mars and Jupiter seems to prove that point.

February 20, 2023February 20, 2023 by Carolyn Collins Petersen

Some Elements Arrived on Earth by Surfing Supernova Shock Waves

Neutron-neutron star mergers are one way that heavy radioactive isotopes of elements found on Earth could be created. Courtesy ESO.

When stars die, they spread the elements they’ve created in their cores out to space. But, other objects and processes in space also create elements. Eventually, that “star stuff” scatters across the galaxy in giant debris clouds. Later on—sometimes millions of years later—it settles onto planets. What’s the missing link between element creation and deposition on some distant world?

February 17, 2023February 17, 2023 by Carolyn Collins Petersen

This is Your Brain on Spaceflight

An MRI scan using of a volunteer's brain for the BRAIN-DTI experiment using tractography to show neural networks. Researchers suspect that astronauts’ brains adapt to living in weightlessness by using previously untapped links between neurons. As the astronauts learn to float around in their spacecraft, left–right and up–down become second nature as these connections are activated. — An MRI scan using of a volunteer's brain for the BRAIN-DTI experiment using tractography to show neural networks. Researchers suspect that astronauts’ brains adapt to living in weightlessness by using previously untapped links between neurons. Credit: University of Antwerpen

When you go to space, it’s going to change your brain. Count on it. That’s because space travelers enter microgravity, and that challenges everything the brain knows about gravity. The experience alters their brain functions and “connectivity” between different regions. It’s all part of the ability of our brains and nervous systems to change in response to changes in the environment, or because of traumatic brain stress or injuries.

February 15, 2023February 15, 2023 by Carolyn Collins Petersen

The Event Horizon Telescope Gazes into the Heart of a Distant Quasar

an artistic concept of a quasar — Concept image of a galactic quasar. Astronomers used the Event Horizon Telescope to study details at the heart of one like this called NRAO 530. Credit: ParallelVision, Pixabay

Oftentimes in astronomy, it takes a village of telescopes and people to make an amazing find. In the case of the quasar NRAO 530, it took a planet full of radio dishes ganged together to peer into its heart. Then, it took a major collaboration of scientists to figure out what the instruments were telling them.

February 13, 2023February 13, 2023 by Carolyn Collins Petersen

Scientists are Simulating Europa in the Lab, Learning What They Can Before Clipper Arrives in 2030

A "true color" image of the surface of Jupiter's moon Europa as seen by the Galileo spacecraft. In 2030, the Europa Clipper mission will start its close flybys of this ocean world. Image credit: NASA/JPL-Caltech/SETI Institute

What’s the best way to learn about Europa before we actually land a mission there? A team of scientists at NASA’s Jet Propulsion Laboratory created a mini version of this icy world in the lab. It’s giving them some fascinating insights into how that moon’s icy surface behaves and providing useful information for planners of the upcoming Europa Clipper flyby mission.

February 9, 2023February 9, 2023 by Carolyn Collins Petersen

Seeing a Mirror Image of the Milky Way From Billions of Years Ago

An artist's impression of our Milky Way Galaxy in its youth, with satellite galaxies and clusters. The newly found Sparkler Galaxy shows similar activity. Credit: James Josephides, Swinburne University. CC BY 4.0.

Ever wonder what our Milky Way Galaxy looked like in its early history? Astronomers using the Webb Telescope (JWST) found another galaxy that’s almost a mirror image of our galaxy as an infant. It’s nicknamed “The Sparkler”. That’s because it has about two dozen glittering globular clusters orbiting around it. There are also a few dwarf galaxies there, being swallowed up by the galaxy.

February 7, 2023February 7, 2023 by Carolyn Collins Petersen

Astronomers Make a New Map of all the Matter (and Dark Matter) in the Universe

A composite model of matter distribution (with dark matter overlay) in a galaxy formation simulation made by the TNG Collaboration.

There’s a lot of matter in the Universe, but not all of it is visible to us. Matter is, essentially, anything that has mass and takes up space. That includes us, the planets, stars, nebulae, and galaxies. It also includes dark matter. It’s all spread out through space.

February 6, 2023February 6, 2023 by Carolyn Collins Petersen

Face-on View of Galaxy NGC 4303 Reveals its Arms are Filled with Active Star Formation

NGC 4303, a galaxy rich in star formation. It lies about 55 million light-years away in the Virgo Cluster. This view shows both visible-light and millimeter-wavelength views of the galaxy. Credit: ESO/ALMA (ESO/NAOJ/NRAO)/PHANGS

Galaxies fill a lot of roles in the universe. The most obvious one is star formation factories. Without that activity, the cosmos would be a very different place. The European Southern Observatory and the Atacama Large Millimeter Array recently zeroed in on the galaxy NGC 4303. Their goal: to take a multi-wavelength view of its star formation activity.