Carolyn Collins Petersen, Author at Universe Today

August 8, 2022August 8, 2022 by Carolyn Collins Petersen

With Martian air, Dirt, and Sunshine, It Should be Possible to Make Iron on Mars

When the first humans reach Mars, they’ll probably live in habitats that were there ahead of time or in habs made from their landers. Eventually, though, if people are going to settle on Mars in large numbers, they’ll need to become self-sufficient. A group of researchers at Swinburne University in Melbourne, Australia is looking at ways to make it happen. Their goal is in-situ resource utilization on the planet for solutions to building out the materials needed for Mars cities. They’ve come up with a proposal to produce metals for use on Mars, using only what’s available on the planet. It’s the first detailed study of its kind focused on metal production at another world. It has further implications for colonies on the Moon, as well.

August 7, 2022August 7, 2022 by Carolyn Collins Petersen

Dwarf Galaxies Found Without Influence From Dark Matter

Dwarf galaxy in Fornax. — The dwarf galaxy NGC1427A flies through the Fornax galaxy cluster and undergoes disturbances which would not be possible if this galaxy were surrounded by a heavy and extended dark matter halo, as required by standard cosmology. Courtesy ESO.

Ask astronomers about dark matter and one of the things they talk about is that this invisible, mysterious “stuff” permeates the universe. In particular, it exists in halos surrounding most galaxies. The mass of the halo exerts a strong gravitational influence on the galaxy itself, as well as on others in the neighborhood. That’s pretty much the standard view of dark matter and its influence on galaxies. However, there are problems with the idea of those halos. Apparently, some oddly shaped dwarf galaxies exist that look like they have no halos. How could this be? Do they represent an observationally induced challenge to the prevailing ideas about dark matter halos?

August 3, 2022August 3, 2022 by Carolyn Collins Petersen

JWST Turns Its Gaze on the Cartwheel Galaxy

The Cartwheel Galaxy, also known as ESO 350-40, is one disturbed-looking piece of cosmic real estate. To look at it now, especially in the latest JWST view, you’d never know it used to be a gorgeous spiral galaxy. That was before it got involved in a head-on collision with a companion. The encounter happened somewhere around 200-300 million years ago. Essentially, the smaller galaxy “bulls-eyed” the Cartwheel, right through its heart. A shock wave swept through the system, changing everything. The aftermath is what we see in this latest image from JWST.

July 31, 2022July 31, 2022 by Carolyn Collins Petersen

Stellar Flybys Leave a Permanent Mark on Newly Forming Planetary Systems

Artist’s impression of one of the two stars in the FU Orionis binary system, surrounded by an accreting disk of material. What has caused this star — and others like it — to dramatically brighten? [NASA/JPL-Caltech] — Artist’s impression of one of the two stars in the FU Orionis binary system, surrounded by an accreting disk of material. Credit: NASA/JPL-Caltech

What do UX Tauri, RW Aurigae, AS 205, Z CMajoris, and FU Orionis have in common? They’re young stellar systems with disks where planets could form. It appears those disks were disturbed by stellar flybys or other close encounters in the recent past. Astronomers want to know: did those events disrupt planet formation in the disks? What do they do? Does this happen in other systems? And, did our own solar system experience a strange encounter in its youth?

July 30, 2022July 30, 2022 by Carolyn Collins Petersen

Earth’s Magnetic Field Almost Completely Collapsed 550 Million Years Ago

Visual simulation of the Earth's magnetic field. Credit: NASA Goddard Space Flight Center

More than half a billion years ago, Earth experienced an almost-complete collapse of its magnetic field. It began in the early Cambrian period. Then, after a period of about 15 million years, the field began to grow again. The cause of that collapse and the bounceback of the field was a mystery. Then, a group of geologists studied rocks from Oklahoma that were created during that time. Magnetic markers in the rocks’ minerals pointed toward an event that began some 550 million years ago. That was before the introduction of multicellular life on our planet.

July 27, 2022July 27, 2022 by Carolyn Collins Petersen

Engineers are Testing how VIPER can Handle the Gnarliest Lunar Terrain

An illustration of NASA's VIPER lunar rover. It'll explore the Moon's south pole and map water resources. Image Credit: NASA Ames/Daniel Rutter

NASA’s getting ready to send a VIPER to the Moon. Not the popular sports car but a rugged vehicle that can handle whatever the lunar surface can throw at it. The Volatiles Investigating Polar Exploration Rover (VIPER) was put through its paces recently at the Glenn Research Center in Cleveland. The prototype drove up test slopes and clambered over boulders and craters. It also made its way through a simulated quicksand type of soil in a “sink tank”. It passed with flying colors, and showed engineers how it will handle similar conditions on the Moon.

July 27, 2022July 27, 2022 by Carolyn Collins Petersen

The Heaviest Neutron Star Ever Seen Got There by Feasting on its Companion

Life’s not too good if you’re the companion of a black widow. Here on Earth, spiders by that name feast on their smaller significant others after mating. Out in space, some weird objects do the same thing to their closeby neighbors. They’re rapidly spinning neutron stars that slowly destroy their companion stars with powerful outflows of high-energy particles. A team at the University of California Berkeley is studying one of these so-called “black widow pulsars”, called PSR J0952-0607. Thanks to its hefty appetite, it shredded and consumed nearly all of its stellar companion. That eating spree made it the heaviest known neutron star to date.

July 25, 2022July 25, 2022 by Carolyn Collins Petersen

The Sun is Eroding Asteroids

The asteroid Bennu from a distance of 24 km (15) miles captured by the PolyCam on OSIRIS-REx. The spacecraft has detected water on Bennu. On the bottom right in the termination line is the large boulder. The image is a mosaic constructed of 12 images. Image Credit: NASA/Goddard/University of Arizona.

Asteroids have been around since early solar system times. However, just because they are ancient bits of history doesn’t mean they don’t change. They collide, they break apart, and now, it turns out their surfaces can erode. That’s due to heat from the Sun. It fractures surface rocks on asteroids and causes what’s called “surface regeneration”. Over time, the cracked and shattered materials can scatter across the surface or even get ejected into space.

How do we know about this erosion? Planetary scientists working on the OSIRIS-REx mission noticed that the surface of asteroid Bennu has rock fractures caused by solar heating. They found that it takes the Sun only about 10,000 to 100,000 years to break up surface rocks on asteroids. This results in a young surface topography on a piece of solar system real estate that’s billions of years old.

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.