Carolyn Collins Petersen, Author at Universe Today

April 18, 2023April 18, 2023 by Carolyn Collins Petersen

Neutron Star Behaves Like a Mini-quasar

MIT astronomers mapped the “disk winds” associated with the accretion disk around Hercules X-1, a system in which a neutron star is drawing material away from a sun-like star, represented as the teal sphere. The findings may offer clues to how supermassive black holes shape entire galaxies. Credits:Credit: Jose-Luis Olivares, MIT. Based on an image of Hercules X-1 by D. Klochkov, European Space Agency.

There’s a wobbly X-ray-bright binary object in our galaxy called Hercules X-1 that’s blowing a mighty wind off to surrounding space. The system consists of a neutron star paired with a sun-like star. The neutron star is drawing material away from its companion. Its resulting accretion spins rapidly, and that whips up powerful winds. They affect the region of nearby space. That’s eerily similar to how a quasar’s central black hole sends out winds to influence its entire host galaxy.

April 15, 2023April 15, 2023 by Carolyn Collins Petersen

NASA Plans Threaten the Future of New Horizons

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 New Horizons mission currently flying through the Kuiper Belt could be facing an unexpected change of plans. NASA’s Science Mission Directorate is soliciting input on turning the spacecraft into a heliospheric science probe. The agency wants to do it much sooner than mission planners intended. If that happens, it will stop further planned planetary exploration of objects in that distant regime of the Solar System.

April 12, 2023April 12, 2023 by Carolyn Collins Petersen

Not Snowball Earth, More of a Slushball Earth

DNDXCB View of Earth 650 million years ago during the Marinoan glaciation. the idea of Slushball Earth may change how we view that past ice age. Credit: University of St. Andrews. — Artist's impression of Earth 650 million years ago during the Marinoan glaciation. Credit: University of St. Andrews.

Our planet hasn’t always been the warm, inviting place we know today. At least five times in its history, Earth froze over, locked in the grip of an ice age. Scientists sometimes refer to these periods as “Snowball Earth.” The popular idea is that everything was covered with ice, making life difficult, if not impossible. But, there’s new evidence that during at least one of these icy periods, parts of Earth’s surface could have been more like a giant mushy ball of slush.

April 10, 2023April 10, 2023 by Carolyn Collins Petersen

It’s Time for Supernova Remnant Cassiopeia A to Get the JWST Treatment

Cassiopeia A (Cas A) is a supernova remnant. It has been observed many times. This new image uses data from Webb’s Mid-Infrared Instrument (MIRI) to reveal Cas A in a new light. Credits: NASA, ESA, CSA, D. D. Milisavljevic (Purdue), T. Temim (Princeton), I. De Looze (Ghent University). Image Processing: J. DePasquale (STScI)

Ready for another stunning image from JWST? How about a peek inside a supernova remnant? Not just any stellar debris, but a highly detailed view of the leftovers from the explosion that created Cassiopeia A. The latest image is giving astronomers an up-close and personal look at what happened to a supermassive star some 11,000 light-years away from us. It may also help answer questions about the existence of cosmic dust, particularly in the early Universe.

April 6, 2023April 6, 2023 by Carolyn Collins Petersen

Do Repeating Radio Signals Indicate an Exoplanet with a Magnetosphere?

An artist's conceptual rendering of interactions between a prospective exoplanet and its star. Plasma emitted from the star is deflected by the exoplanet's magnetic field (and magnetosphere) then interacts with the star's magnetic field, resulting in an aurora on the star and the emission of radio waves. Credit: National Science Foundation/Alice Kitterman — An artist's conceptual rendering of interactions between a prospective exoplanet and its star. Plasma emitted from the star is deflected by the exoplanet's magnetic field then interacts with the star's magnetic field, resulting in an aurora on the star and the emission of radio waves. Credit: National Science Foundation/Alice Kitterman

There’s an interesting problem in exoplanet studies: how to tell if a planet has a magnetosphere. It’s not like we can visibly see it unless we find a different way of looking. A pair of scientists may have found one. They used radio telescopes to track emissions given off by magnetic star-planet interactions. These happen when a planet with a magnetic field plows through star stuff caught its star’s magnetic field.

April 4, 2023April 4, 2023 by Carolyn Collins Petersen

Global Sea Levels Rose by 0.27 cm from 2021 to 2022

An aerial view of the icebergs near Kulusuk Island, off the southeastern coastline of Greenland, a region that is exhibiting an accelerated rate of ice loss. The water runs off into the ocean and is contributing to sea level rise. Credits: NASA Goddard Space Flight Center

It probably comes as no surprise to people living in low-lying coastal regions, but sea waters are rising by large, measurable amounts. That assessment comes from NASA, which has analyzed 30 years of sea-level satellite measurements. The news is not good. Since 1993, the seas rose by a total of 9.1 centimeters. Two years ago, it went up by 0.27 centimeters.

March 31, 2023March 30, 2023 by Carolyn Collins Petersen

Now We Know How a Solar Storm Took Out a Fleet of Starlinks

A view of an auroral storm from the ISS. Aurorae are one effect of solar storms like the one that took out 39 Starlink satellites in 2022. Credit: NASA/ESA/Tim Peake — A view of an auroral storm from the ISS. Credit: NASA/ESA/Tim Peake

On March 23rd, sky observers marveled at a gorgeous display of northern and southern lights. It was reminder that when our Sun gets active, it can spark a phenomenon called “space weather.” Aurorae are among the most benign effects of this phenomenon.

March 30, 2023March 30, 2023 by Carolyn Collins Petersen

Plans are Underway to Build a 30 Cubic Kilometer Neutrino Telescope

Underwater neutrino detectors take advantage of location to track these fast particles. This is an artist's impression of a KM3NeT installation in the Mediterranean. Chinese scientists hope to build a bigger underwater "neutrino telescope" in the next few years. Courtesy Edward Berbee/Nikhef.

How do astronomers look for neutrinos? These small, massless particles whiz through the universe at very close to the speed of light. They’ve been studied since the 1950s and detecting them provides work for a range of very interesting observatories.

March 28, 2023March 28, 2023 by Carolyn Collins Petersen

Are We Alone? The Answer Might Be in Space Dust That’s All Around Us

When an asteroid hit the Yucatan peninsula 65 million years ago it through Earth debris to space. Could that debris carry evidence of life? And, could such an event at an alien planet carry evidence of its life to us on dust particles generated in the impact? Image courtesy Don Davis.

When it comes to looking for extraterrestrial life “out there” astronomers scan distant planets. They also look for technosignatures at alien worlds. What if the answer they seek is dust blowing on the interstellar winds?

March 27, 2023March 27, 2023 by Carolyn Collins Petersen

Why Does ‘Oumuamua Follow Such a Bizarre Orbit? Hydrogen Outgassing

An artist’s depiction of the interstellar comet ‘Oumuamua, as it warmed up in its approach to the sun and outgassed hydrogen (white mist), which slightly altered its orbit. The comet, which is most likely pancake-shaped, is the first known object other than dust grains to visit our solar system from another star. (Image credit: NASA, ESA and Joseph Olmsted and Frank Summers of STScI)

Nothing excites space enthusiasts like a good alien mystery. The interstellar visitor ‘Oumuamua presented one as it moved through the inner solar system in 2017. At least one scientist has insisted that this pancake-shaped object is an alien spacecraft. That’s because of the way it accelerated away from the Sun as it passed through. However, a number of planetary scientists say its activity might be more comet-like—something fairly common in the solar system.