Nancy Atkinson, Author at Universe Today

January 16, 2024January 16, 2024 by Nancy Atkinson

Machine Learning Could Find all the Martian Caves We Could Ever Want

Examples of potential cave entrances (PCEs) on Mars and their assigned category from the Mars Global Candidate cave Catalogue (MGC3). Credit: NASA/JPL/MSSS/The Murray Lab.

The surface of Mars is hostile and unforgiving. But put a few meters of regolith between you and the Martian sky, and the place becomes a little more habitable. Cave entrances from collapsed lava tubes could be some of the most interesting places to explore on Mars, since not only would they provide shelter for future human explorers, but they could also be a great place to find biosignatures of microbial life on Mars.

But cave entrances are difficult to spot, especially from orbit, as they blend in with the dusty background. A new machine learning algorithm has been developed to quickly scan images of the Martian surface, searching for potential cave entrances.

January 11, 2024January 11, 2024 by Nancy Atkinson

Satellite Data Shows US East Coast is Sinking

Map shows vertical land motion along the East Coast. The yellow, orange and red areas on these maps denote areas of sinking. Image courtesy of Leonard Ohenhen.Virginia Tech.

Based on satellite imagery, geologists have determined major cities on the U.S. Atlantic coast are sinking, some areas as much as 2 to 5 millimeters (.08-0.2 inches) per year. Called subsidence, this sinking of land is happening at a faster rate than was estimated just a year ago. In a new paper published in the Proceedings of the National Academies of Sciences, researchers say their analysis has far-reaching implications for community and infrastructure resilience planning, particularly for roadways, airport runways, building foundations, rail lines, and pipelines.

January 10, 2024January 10, 2024 by Nancy Atkinson

A Solo Brown Dwarf Found With Auroras

This artist concept portrays the brown dwarf W1935, which is located 47 light-years from Earth. Astronomers using NASA’s James Webb Space Telescope found infrared emission from methane coming from W1935, generating an aurora, a very unexpected discovery. Credit: NASA, ESA, CSA, Leah Hustak (STScI)

Astronomers have used JWST to find a brown dwarf with polar auroras like the Earth, or Jupiter. This is surprising because the brown dwarf, dubbed W1935, is a free-floating object, meaning it isn’t part of another star system. Therefore, there’s no solar wind available to generate any Northern Lights. Instead, the auroras are seemingly generated from methane emissions in the planet’s atmosphere, interacting with the interstellar plasma. Another theory is that it perhaps has an active but unseen moon contributing to the emissions.

January 8, 2024January 8, 2024 by Nancy Atkinson

JWST and Chandra Team Up for a Stunning View of Supernova Remnant Cassiopeia A

This image of Cassiopeia A comes from a combination of data from the Chandra X-ray telescope and the James Webb Space Telescope. Credit: X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; IR: NASA/ESA/CSA/STScI/Milisavljevic et al., NASA/JPL/CalTech; Image Processing: NASA/CXC/SAO/J. Schmidt and K. Arcand

NASA’s long-lived Chandra X-ray Observatory teamed up with JWST for the first time, producing this incredibly detailed image of the famous supernova remnant Cassiopeia A. JWST first looked at the remnant in April 2023, and noticed an unusual debris structure from the destroyed star, dubbed the “Green Monster.” The combined view has helped astronomers better understand what this unusual structure is, plus it uncovered new details about the explosion that created Cas A.

January 4, 2024January 4, 2024 by Nancy Atkinson

Astronomers Test an Exoplanet Instrument on Jupiter

NASA’s Juno spacecraft captured this view of Jupiter during the mission’s 40th close pass by the giant planet on Feb. 25, 2022. The large, dark shadow on the left side of the image was cast by Jupiter’s moon Ganymede. Image data: NASA/JPL-Caltech/SwRI/MSSS Image processing by Thomas Thomopoulos

The European Southern Observatory’s Very Large Telescope (VLT) has a high-resolution spectrograph called ESPRESSO, designed specifically to detecting and characterize exoplanets. Astronomers recently ran a test with the instrument, studying the atmosphere and winds of Jupiter. They used a technique called Doppler velocimetry to measure the reflection of light from the Sun in the planet’s clouds, allowing for instantaneous measurement of the clouds’ wind speeds. The technique has also been used on Venus and will guide the future study of exoplanets.

January 3, 2024January 3, 2024 by Nancy Atkinson

Watch a Full Martian Day, From Dawn to Dusk

Curiosity’s rear Hazcam captured the shadow of the back of the rover in this 12-hour view looking toward the floor of Gale Crater. A variety of factors caused several image artifacts, including a black speck, the distorted appearance of the Sun, and the rows of white pixels that streak out from the Sun. NASA/JPL-Caltech

On November 8th, NASA’s Curiosity Rover paused its incessant science work and just watched the day unfold on Mars. The rover used its black-and-white Hazard-Avoidance Cameras (Hazcams) to watch an entire 12-hour day on Mars as the shifting Sun cast shadows across the Martian landscape. NASA chose this day because of the Mars solar conjunction when the Sun interferes with communications with the Red Planet, meaning the rover doesn’t do any roving about. The timelapse comprises 25 frames from both the front and rear Hazcams.

December 22, 2023December 22, 2023 by Nancy Atkinson

Questions Remain on Chinese Rocket That Created an Unusual Double Crater on the Moon

A rocket body impacted the Moon on March 4, 2022, near Hertzsprung crater, creating a double crater roughly 28 meters wide in the longest dimension. Credits: NASA/Goddard/Arizona State University

In November, we reported how an impact on the Moon from a Chinese Long March rocket booster created an unusual double crater. For a single booster to create a double crater, some researchers thought there must have been an additional – perhaps secret – payload on the forward end of the booster, opposite from the rocket engines. But that may not necessarily be the case.

Other researchers feel the extra mass wasn’t anything secretive, but possibly an inert structure such as a payload adapter added to the rocket to support the primary mission payload.

December 21, 2023December 21, 2023 by Nancy Atkinson

It’s Time for Saturn’s “Spokes” to Return

This NASA Hubble Space Telescope photo of Saturn reveals the planet's cloud bands and a phenomenon called ring spokes. NASA, ESA, STScI, Amy Simon (NASA-GSFC)

Astronomers have been observing Saturn with the Hubble Space Telescope and several other spacecraft for decades and have noticed something unusual. During seasonal changes, transient spoke-like features appear in the rings. These dark, ghostly blobs orbit around the planet 2-3 times, and then disappear.

As Saturn is approaching its equinox, this is prime spoke activity time. Once again, Hubble has been called to gaze at Saturn, tracking the behavior of the spokes and hopefully giving astronomers more clues as to why they occur.

December 21, 2023December 21, 2023 by Nancy Atkinson

Finally. A Productive Use for Nuclear Weapons: Asteroid Defense

Four different asteroids and how nuclear ablation affects asteroids of different makeups. — A modeling tool developed by scientists at Lawrence Livermore National Laboratory shows the progression an asteroid being broken up by a theoretical nuclear device detonated near the the surface of the near-Earth object. Graphic illustration courtesy of Mary Burkey.

While it has been a favorite disaster movie theme, nuking an incoming asteroid in the real world has been touted as a very bad idea. While a nuclear bomb could possibly obliterate a smaller asteroid, nuking a larger asteroid would only break it into pieces. Those pieces would still threaten our planet, and perhaps even makes things worse by producing multiple impacts across the planet.

But is using nuclear weapons on an incoming asteroid really a bad idea? If the right technique is used, a nuclear blast could possibly be used as an asteroid deflection device.

December 20, 2023December 21, 2023 by Nancy Atkinson

Enjoy the Holiday-Themed Christmas Tree Cluster

The Christmas Tree Cluster, (NGC 2264). Credit: X-ray: NASA/CXC/SAO; Optical: T.A. Rector (NRAO/AUI/NSF and NOIRLab/NSF/AURA) and B.A. Wolpa (NOIRLab/NSF/AURA); Infrared: NASA/NSF/IPAC/CalTech/Univ. of Massachusetts; Image Processing: NASA/CXC/SAO/L. Frattare & J.Major

Just in time for the holidays, a new composite image of the Christmas Tree Cluster (NGC 2264) has been released. This image is a group effort: the blue and white stars in the cluster giving off X-rays are seen by Chandra, while the faint green nebula was imaged by the WIYN 0.9-meter telescope on Kitt Peak.