Universe Today

November 7, 2022November 7, 2022 by Andy Tomaswick

Want a Sneak Peek From NASA’s Lucy Mission? Here are Some Photos it Took of the Moon During its Flyby

We reported a few weeks ago about an Earth gravity assist flyby for the Lucy mission. Around the same as the spacecraft took a dip closer to Earth than the ISS, it took some fantastic pictures of our nearest neighbor – the Moon. After some processing, those pictures are available for inspection or gawking, as the case may be.

November 7, 2022February 7, 2023 by Matt Williams

Hubble saw Multiple Light Echoes Reflecting off Rings of Dust From a Supernova Explosion

Artist view of a supernova explosion. Credit: NASA

When stars reach the end of their life cycle, they experience gravitational collapse at their centers and explode in a fiery burst (a supernova). This causes them to shed their outer layers and sends an intense burst of light and high-energy short-wavelength radiation (like X-rays and gamma-rays) out in all directions. This process also creates cosmic rays, which consist of protons and atomic nuclei that are accelerated to close to the speed of light. And on rare occasions, supernovae can also create “light echoes,” rings of light that spread out from the site of the original explosion.

These echoes will appear months to years after the supernova occurs as light from the explosion interacts with the layers of dust in the vicinity. Using the Hubble Space Telescope (HST), an international team of astronomers was able to document the emergence and evolution of multiple light echoes (LEs). The team traced these echoes to a stripped-envelope supernova (SN 2016adj) located in the central dust lane of Centaurus A, a galaxy located 10 to 16 million light-years away in the constellation of Centaurus.

November 7, 2022November 7, 2022 by Brian Koberlein

Can JWST see Galaxies Made of Primordial Stars?

The distance of first generation stars. Credit: STScI

All stars are composed of mostly hydrogen and helium, but most stars also have measurable amounts of heavier elements, which astronomers lump into the category of “metals.” Our Sun has more metals than most stars because the nebula from which it formed was the remnant debris of earlier stars. These were in turn children of even earlier stars, and so on. Generally, each new generation of stars has a bit more metal than the last. The very first stars, those born from the primordial hydrogen and helium of the cosmos, had almost no metal in them. We’ve never seen one of these primordial stars, but with the power of the Webb and a bit of luck, we might catch a glimpse of them soon.

November 7, 2022November 7, 2022 by Carolyn Collins Petersen

Hydrothermal Vents Under the Arctic Ice are Perfect Places to Practice Exploring Europa

This illustration of Europa (foreground), Jupiter (right) and Io (middle) is an artist's concept showing possible oceanic volcanoes under its icy surface. Image Credit: NASA/JPL-Caltech

Someday on Europa, there’ll be a robotic explorer diving beneath its icy surface to find volcanoes. Yes, even though it’s an ice world, Europa shows signs of internal activity. Planetary scientists think volcanic features, similar to hydrothermal vents here on Earth, exist on Europa’s ocean floor. But, how to understand them?

November 7, 2022November 6, 2022 by Scott Alan Johnston

Planets Make it Harder to Figure out a Star’s age

Active star, nearby exoplanet, and inactive companion star for NASA's Chandra X-ray Observatory. 2022

Estimating stellar age has always been a challenge for astronomers. Now, a certain class of exoplanets is making the process even more complicated. Hot Jupiters – gas giants with orbital periods smaller than that of Mercury – appear to have an anti-aging effect on their stars, according to a new study. These enormous planets inflict both magnetic and tidal interference on their host star, speeding up the star’s rotation and causing them to emit X-rays more energetically, both of which are hallmarks of stellar youth. The result calls into question some of what we previously believed about stellar age, and offers a glimpse at the ongoing interconnectivity between a star and its planets long after their formation.

November 6, 2022November 6, 2022 by Matt Williams

Mars is Mostly Dead. There's Still Magma Inside, so it's Slightly Alive

Artist's concept of InSight "taking the pulse of Mars". Credit: NASA/JPL-Caltech

Since February 2019, NASA’s Interior Exploration using Seismic Investigations, Geodesy and Heat Transport (InSight) lander has been making the first-ever measurements of tectonics on another planet. The key to this is InSight’s Seismic Experiment for Interior Structure (SEIS) instrument (developed by seismologists and geophysicists at ETH Zurich), which has been on the surface listening for signs of “marsquakes.” The dataset it has gathered (over 1,300 seismic events) has largely confirmed what planetary scientists have long suspected: that Mars is largely quiet.

However, a research team led by ETH Zurich recently analyzed a cluster of more than 20 recent marsquakes, which revealed something very interesting. Based on the location and spectral character of these events, they determined that most of Mars’ widely distributed surface faults are not seismically active. Nevertheless, most of the 20 seismic events observed originated in the vicinity of Cerberus Fossae, a region consisting of rifts (or graben). These results suggest that geological activity and volcanism still play an active role in shaping the Martian surface.

November 6, 2022November 2, 2022 by Paul M. Sutter

When Black Holes Collide They Also Produce Neutrinos

Still image from a numerical simulation of an unequal mass binary black hole merger, with parameters consistent with GW190412. [Image credit: N. Fischer, H. Pfeiffer, A. Buonanno (Max Planck Institute for Gravitational Physics), Simulating eXtreme Spacetimes project]

Ever since astronomers first detected ultra high energy neutrinos coming from random directions in space, they have not been able to figure out what generates them. But a new hypothesis suggests an unlikely source: the mergers of black holes.

November 5, 2022November 5, 2022 by Anton Pozdnyakov

Worrying Solar Storm Data, Falcon Heavy is Back, Total Lunar Eclipse

Historical data about solar storms carved in trees, and it’s a bit worrying. Falcon Heavy’s back after 40 months of absence. There’s a meteor shower and a total lunar eclipse in the coming days. And JWST gave us yet another version of Pillars of Creation.

November 5, 2022November 2, 2022 by Paul M. Sutter

It’s Tough to Find Evidence of Stars Eating Planets

Tragically sometimes stars engulf their own planets. While most stars are able to quickly cover up the evidence for their crime, a new study by astronomers has revealed that in some cases the evidence can linger for up to two billion years.

November 5, 2022November 10, 2022 by Brian Koberlein

A Black Hole’s X-Rays are Coming From a Region 2,000 km Away From the Singularity Itself

Artist’s conception of the Cygnus X-1 system. Credit: John Paice

In 1961 astronomers discovered a powerful x-ray source coming from the constellation Cygnus. Not knowing what it was, they named the source Cygnus X-1. It’s one of the strongest x-ray sources in the sky, and we now know it is powered by a stellar-mass black hole. Since it is only about 7,000 light-years away, it also gives astronomers an excellent view of how stellar-mass black holes behave. Even after six decades of study, it continues to teach us a few things, as a recent study in Science shows.