Carolyn Collins Petersen, Author at Universe Today

June 23, 2023June 23, 2023 by Carolyn Collins Petersen

Mind-Blowing Animation Shows What the World Would Look Like If You Could See Carbon Dioxide Emissions

A map of carbon dioxide in atmosphere from various sources during 2021. CourtesyNASA's Scientific Visualization Studio — A map of carbon dioxide in atmosphere over North America from various sources during 2021. CourtesyNASA's Scientific Visualization Studio

It’s a strange, eerie-looking place. Carbon dioxide gas appears… and disappears in cycles and bursts throughout the year. It’s how our planet would look if we could detect carbon dioxide (CO₂) with our eyes. Scientists at NASA’s Global Modeling and Assimilation Office made computer animations of its presence in our atmosphere. Those videos show an almost-alien view of Earth under the influence of this gas.

June 21, 2023June 21, 2023 by Carolyn Collins Petersen

The Milky Way’s Supermassive Black Hole had a Burst of Activity 200 Years Ago. We Just Saw the Echo.

Imagery from NASA’s Imaging X-ray Polarimetry Explorer and Chandra X-ray Observatory have been combined to show X-ray data of the area around Sagittarius A*, the supermassive black hole at the core of the Milky Way galaxy. The lower panel combines IXPE data, in orange, with Chandra data in blue. The upper panel depicts a much wider field-of-view of the center of the Milky Way, courtesy of Chandra. The thin white lines layered onto the top panel frame the highlighted area, and indicate that the perspective in the bottom panel has been rotated approximately 45 degrees to the right. The combination of IXPE and Chandra data helped researchers determine that the X-ray light identified in the molecular clouds originated from Sagittarius A* during an outburst approximately 200 years ago. Credits: IXPE: NASA/MSFC/F. Marin et al; Chandra: NASA/CXC/SAO; Image Processing: L.Frattare, J.Major & K.Arcand

We in the Milky Way Galaxy are pretty lucky to have a fairly quiet central supermassive black hole in Sgr A*. It’s not loud and bright like an active galactic nucleus. It appears to be active for brief periods before going to sleep. Two hundred years ago, it “woke up” for about a year and a half and had a bite to eat.

June 20, 2023June 20, 2023 by Carolyn Collins Petersen

Astronomers Find a White Dwarf Pulsar

An artist's conception of a white dwarf pulsar pair. Two are now known. Credit: University of Warwick.

When astronomers talk about the “end states” of stellar evolution, several categories come to mind: black holes, neutron stars/pulsars, and white dwarfs. What happens if one star ends up in two of these states? That’s the case with a genre-breaking white dwarf pulsar called J191213.72-441045.1 (J1912-4410 for short). It’s part of a binary pair that includes a red dwarf star.

June 19, 2023June 19, 2023 by Carolyn Collins Petersen

The Evidence is Building that Dark Matter is Made of Axions

In shaping the Universe, gravity builds a vast cobweb-like structure of filaments tying galaxies and clusters of galaxies together along invisible bridges hundreds of millions of light-years long. A galaxy can move into and out of the densest parts of this web throughout its lifetime. Credit: Volker Springel (Max Planck Institute for Astrophysics) et al.

There’s some potentially big news on the hunt for dark matter. Astronomers may have a handle on what makes this mysterious cosmic stuff: strange particles called “axions.”

June 15, 2023June 15, 2023 by Carolyn Collins Petersen

A Planet So Hot Its Atmosphere Contains the Raw Material for Rocks

An artist's impression of WASP-76b, a planet with an atmosphere so hot it vaporizes metals. Courtesy: International Gemini Observatory/NOIRLab/NSF/AURA/J. da Silva/Spaceengine/M. Zamani

In the annals of “strange new worlds”, the ultra-hot Jupiter planet WASP-76b ranks right up there as a very unusual place. There’s no surface, but it does have a massive, hot atmosphere. Temperatures average a raging 2000 C and rise up to 2400 C in one hemisphere. That’s hot enough for mineral and rock-forming elements like calcium, nickel, and magnesium to get vaporized and float around in that thick blanket of air. Not only that, but iron probably rains down through the clouds.

June 14, 2023June 14, 2023 by Carolyn Collins Petersen

An Element Critical for (Earth) Life is Spewing out of Enceladus

Saturn's moon Enceladus sprays its salty sea out into space. Those plumes are rich in phosphates. (NASA/JPL/SSI/J. Major)

We really need to get back to Enceladus. Not to send people necessarily, although that would be nice. But, we need to get some more robotic missions out there. This moon is one of the most intriguing places in the solar system. Not only has it got oceans under that icy crust, but it’s spewing salty water out to space. Plus, that water seems to be rich in phosphates, which contain phosphorus, which is a building block of life.

June 14, 2023June 14, 2023 by Carolyn Collins Petersen

Curiosity Takes One Final Postcard Image of a Picturesque Valley Before Moving on to its Next Destination

A "postcard" from Mars Curiosity rover combines two images at two different times of day with a color overlay to show the different views. Courtesy NASA/JPL-Caltech — A "postcard" view from Mars Curiosity rover. It combines images from two different times of day with a color overlay to show how the view changes. Courtesy NASA/JPL-Caltech

The Mars rover Curiosity continues to make its way up the slopes of Mount Sharp on Mars. On April 8th, its navigation cameras snapped a pair of images—one in the morning and one in the afternoon. They show distinctly different lighting angles during a crisp Martian winter day. The images got combined with a color overlay to produce a fantastic “postcard” from the Red Planet.

June 12, 2023June 12, 2023 by Carolyn Collins Petersen

Astronomers Have Figured Out Clever Tricks to Reduce the Impact of Satellite Trails

A long-exposure image of the Orion Nebula with a total exposure time of 208 minutes showing satellite trails in mid-December 2019. Credit: A. H. Abolfath

A clear sky is a prerequisite for most astronomers imaging the cosmos. However, with the proliferation of satellite trails, astronomers see a lot more streaks in their images. That’s particularly true for people using professional ground-based and orbiting telescopes. When Hubble Space Telescope opened its eye on the sky, there were less than 500 satellites orbiting our planet. Now, there are nearly 8,000 of them, leaving their mark across the sky.

June 9, 2023June 9, 2023 by Carolyn Collins Petersen

Parker Solar Probe Flies Close Enough to the Sun to See the Source of the Fast Solar Wind

NASA's Parker Solar Probe studies the fast solar wind and its origins on the Sun. Credit: NASA

Where does the solar wind come from? That’s a question solar physicists have wanted an answer to for decades. Now, the Parker Solar Probe is showing them exactly where this stream of particles exits our star on a journey out through interplanetary space.

June 8, 2023June 8, 2023 by Carolyn Collins Petersen

Triggered Star Birth in the Nessie Nebula

A three-color composite of a portion of the Nessie Nebula that shows infrared observations from two Spitzer instruments. The bright red circular region in the center is the site of triggered star formation. Courtesy NASA/JPL. — A three-color composite of a portion of the Nessie Nebula that shows infrared observations from two Spitzer instruments. The bright red circular region in the lower center is the site of triggered star formation. Courtesy NASA/JPL.

Star formation is one of the oldest processes in the Universe. In the Milky Way and most other galaxies, it unfolds in cold, dark creches of gas and dust. Astronomers study sites of star formation to understand the process. Even though they know much about it, some aspects remain mysterious. That’s particularly true for the “Nessie Nebula” in the constellation Vulpecula. An international team led by astronomer James Jackson studies the nebula and its embedded star-birth regions. They found that it experienced a domino effect called “triggered star formation.”