Carolyn Collins Petersen, Author at Universe Today

September 23, 2022September 23, 2022 by Carolyn Collins Petersen

There’s a Blob of Gas Orbiting Around the Milky Way’s Supermassive Black Hole

The Atacama Large Millimeter/submillimeter Array (ALMA) looked at Sagittarius A*, (image of Sag A* by the EHT Collaboration) to study something bright in the region around Sag A*. Credit: ESO/José Francisco Salgado.

Sagittarius A* (Sag A) is usually a pretty quiet object, as supermassive black holes go. It’s not wildly active, like the object at the heart of M87, for example. But, every once in a while, there’s a little action in its neighborhood. Right now, there appears to be a hot blob of gas running rapidly in circles around the black hole. Astronomers detected it using the Atacama Large Millimeter Array (ALMA) in Chile. The data from that radio astronomy facility tells them more about the environment around Sag A*.

September 21, 2022September 21, 2022 by Carolyn Collins Petersen

Habitable Planets Will Most Likely be Cold, Dry “Pale Yellow Dots”

An artist's concept of K2-18b, a super-Earth exoplanet that could support life. But, not all habitable planets are pale blue dots. Some are dry and yellow. Courtesy STScI

Remember all the habitable planets we’ve seen in science fiction movies? There’s wintry Hoth, for example, and overwhelmingly hot Dune. The folks in Interstellar visited an ocean world and a desolate rocky world. For all their differences, these places were still what they call on Star Trek M-class habitable worlds. Sure they weren’t all like Earth, but that made them excitingly alien for the lifeforms they did support. In the real universe, it seems that alien worlds not quite like ours could be the norm. Earth could be the real alien world.

September 19, 2022September 19, 2022 by Carolyn Collins Petersen

Solar Orbiter Captures the First Ever Image of a Magnetic Solar Switchback on the Sun

A Solar Dynamics Observatory view of solar magnetic loops. A Solar Orbiter captured an image of a solar magnetic switchback in loops similar to these. Courtesy NASA/SDO

On March 25, 2022, the ESA/NASA Solar Orbiter spacecraft closed in on the Sun, getting ready to study it during a flyby. Its Metis coronagraph instrument, which blocks out the Sun so the spacecraft can study its outer atmosphere, recorded an image of something strange: a distorted, S-shaped “kink” in a small area of plasma flowing from the Sun. It was a magnetic solar switchback.

September 16, 2022September 16, 2022 by Carolyn Collins Petersen

Saturn Might Have Torn a Moon Apart to Make its Rings

Saturn's rings in all their glory. Image from the Cassini orbiter as Saturn eclipsed the Sun. Image Credit: By NASA / JPL-Caltech / Space Science Institute

Saturn is a world of surprises. The Voyager 1 and 2 flybys and later on, the Cassini mission, opened our collective eyes to intricate details in its rings and atmosphere. They also gave us up-close and personal looks at those amazing moons. But, one thing they didn’t show us was Saturn’s proposed moon Chrysalis. That’s because it doesn’t exist. Well, actually, it is there, but in the form of those dazzling rings.

September 16, 2022September 16, 2022 by Carolyn Collins Petersen

Without Water and Life, Geology on Mars is Driven by the Wind

Murray formation: rocks laid down by water and sculpted by wind — Finely layered rocks within the "Murray formation" layer of lower Mount Sharp on Mars. Credit: NASA

On Earth, we all know what changes our landscapes: water and wind erosion, tectonic activity, and volcanism. Today on Mars, wind-driven erosion is hard at work. Wind is an inexorable sculptor everywhere. And, it might have created places where planetary scientists and astrobiologists hunt for traces of primordial Martian life today.

September 12, 2022September 12, 2022 by Carolyn Collins Petersen

The Webb Image you’ve Been Waiting For: the Orion Nebula

Orion Nebula by JWST — The inner region of the Orion Nebula as seen by the James Webb Space Telescope’s NIRCam instrument. Credit: NASA, ESA, CSA, PDRs4All ERS Team; image processing Salomé Fuenmayor

This is it, folks. Feast your eyes! It’s what we’ve been training for—seeing the James Webb Space Telescope’s first detailed view of the Orion Nebula! JWST’s NIRCam gazed at this starbirth nursery and revealed incredible details hidden from view by gas and dust clouds.

September 9, 2022September 15, 2022 by Carolyn Collins Petersen

Just 2,000 Years Ago, Betelgeuse Was Yellow, Not Red

Artist's impression of Betelgeuse. Credit: ESO/L. Calçada

Compared to the lifespan of stars, human lives are pretty short. Stars such as Betelgeuse (in Orion) live for millions of years. Others exist for billions of years. We (if we’re lucky) get maybe 100 years (more or less). So, to us, stars don’t appear to change much over our lifetimes, unless they blow up as supernovae. But, what about over the course of 20 or 30 successive lifetimes?

September 5, 2022September 5, 2022 by Carolyn Collins Petersen

What’s Being Done to Protect Astronauts From Radiation in Deep Space?

astronauts faced possible radiation dangers on the Moon. — Apollo 17 astronaut Harrison "Jack" Schmitt at Tracy Rock on the lunar surface. If a solar storm had hit the Moon while the astronauts were on the surface exploring, it could have been a disaster. Credit: NASA.

In 1982, author James Michener published his sprawling Space Race novel, Space. In it, he describes a fictional Apollo 18 mission to the Moon. While the astronauts are on the surface, the Sun unleashes a huge storm, trapping them outside of their protective capsule. The two men get blasted by lethal amounts of radiation before they can get to safety.

September 1, 2022September 1, 2022 by Carolyn Collins Petersen

Yeast Will Fill in for Humans on Artemis I, Soaking up a Lunar Mission’s Worth of Radiation

SLS and Orion at launch pad — A full Moon looms over NASA's Space Launch System and its Orion capsule containing yeast cells bound for an epic trip. (NASA Photo / Ben Smegelsky)

When Artemis 1 finally takes flight (possibly this Saturday), twelve bags of baker’s yeast will go along for the ride. Millions of these cells of Saccharomyces cerevisiae will experience deep space as it grows and reproduces. The yeast is a stand-in for actual people. The idea is to see what threat the radiation environment in deep space poses to living cells. The data from the experiment will point to how genetic engineering might help reduce damage to astronauts.

August 31, 2022August 31, 2022 by Carolyn Collins Petersen

Astronomers Find the Oldest Planetary Nebula

Abell 39 is a good example of a planetary nebula, similar to the one discovered in M37. Credit: WIYN/NOAO/NSF

Planetary nebulae are short-lived “leftovers” of sun-like stars. Most of these “star ghosts” only last—at most—about 25,000 years. Usually, their clouds of debris disperse so broadly that they fade out fairly quickly. However, there’s one that has lasted at least 70,000 years. That makes it a “grande dame” of planetary nebulae.