Astronomy Archives

December 22, 2022December 22, 2022 by Evan Gough

A Star Came too Close to a Black Hole. It Didn’t End Well

A disk of hot gas swirls around a black hole in this illustration. The stream of gas stretching to the right is what remains of a star that was pulled apart by the black hole. A cloud of hot plasma (gas atoms with their electrons stripped away) above the black hole is known as a corona. Credits: NASA/JPL-Caltech

Black holes are confounding objects that stretch physics to its limits. The most massive ones lurk in the centers of large galaxies like ours. They dominate the galactic center, and when a star gets too close, the black hole’s powerful gravitational force tears the star apart as they feed on it. Not even the most massive stars can resist.

But supermassive black holes (SMBHs) didn’t start out that massive. They attained their gargantuan mass by accreting material over vast spans of time and by merging with other black holes.

There are large voids in our understanding of how SMBHs grow and evolve, and one way astrophysicists fill those voids is by watching black holes as they consume stars.

December 21, 2022December 21, 2022 by Evan Gough

Webb Stares Deeply Into the Universe, Showing How Galaxies Assemble

This image represents a portion of the full PEARLS field, which will be about four times larger. Thousands of galaxies over an enormous range in distance and time are seen in exquisite detail, many for the first time. Image Credit: SCIENCE: NASA, ESA, CSA, Rolf A. Jansen (ASU), Jake Summers (ASU), Rosalia O'Brien (ASU), Rogier Windhorst (ASU), Aaron Robotham (UWA), Anton M. Koekemoer (STScI), Christopher Willmer (University of Arizona), JWST PEARLS Team IMAGE PROCESSING: Rolf A. Jansen (ASU), Alyssa Pagan (STScI)

The James Webb Space Telescope is delivering a deluge of images and data to eager scientists and other hungry-minded people. So far, the telescope has shown us the iconic Pillars of Creation like we’ve never seen them before, the details of very young stars as they grow inside their dense cloaks of gas, and a Deep Field that’s taken over from the Hubble’s ground-breaking Deep Field and Ultra Deep Field images. And it’s only getting started.

True to its main science objectives, the JWST has peered back in time to the Universe’s earliest galaxies looking for clues to how they assemble and evolve.

December 19, 2022January 28, 2023 by Matt Williams

Hubble and Spitzer Team up to Find a Pair of Waterworld Exoplanets

Artist’s impression of a water world, where half of its mass consists of water. Just like our Moon, the planet is bound to its star by tidal forces and always shows the same face to its host star. Credit: Pilar Montañés

As of December 19th, 2022, 5,227 extrasolar planets have been confirmed in 3,908 systems, with over 9,000 more awaiting confirmation. While most of these planets are Jupiter- or Neptune-sized gas giants or rocky planets many times the size of Earth (Super-Earths), a statistically significant number have been planets where water makes up a significant part of their mass fraction – aka. “water worlds.” These planets are unlike anything we’ve seen in the Solar System and raise several questions about planet formation in our galaxy.

In a recent study, an international team led by researchers from the University of Montreal’s Institute for Research on Exoplanets (iREx) found evidence of two water worlds in a single planetary system located about 218 light-years away in the constellation Lyra. Based on their densities, the team determined that these exoplanets (Kepler-138c and Kepler-138d) are lighter than rocky “Earth-like” ones but heavier than gas-dominated ones. The discovery was made using data from NASA’s now-retired Spitzer Space Telescope and the venerable Hubble Space Telescope.

December 19, 2022December 19, 2022 by Evan Gough

JWST Sees Furious Star Formation in a Stellar Nursery

Image of the Carina Nebula (NGC 3324) captured by Webb’s Near-Infrared Camera (NIRCam), Credit: NASA/ESA/CSA/STScI

The powerful James Webb Space Telescope is a mighty technological tool. Astrophysicists first conceived it over 20 years ago, and after many twists and turns, it was launched on December 2st, 2021. Now it’s in a halo orbit at the Sun-Earth L2 point, where it will hopefully continue operating for 20 years.

It’s only been a few months since its first images were released, and it’s already making progress in answering some of the Universe’s most compelling questions. In a newly-released image, the JWST peered deep inside massive clouds of gas and dust to watch young stars come to life in their stellar cocoons.

December 17, 2022December 17, 2022 by Anton Pozdnyakov

Accident on the ISS, JWST Deep Field, Space Habitat Goes BANG!

Splashdown! Artemis I has returned home. Webb has made its first Deep Field survey. Listen to the sound of a dust devil on Mars, and a Space journalist is going to the Moon.

December 16, 2022December 16, 2022 by Matt Williams

Aztecs Used an Extremely Accurate Solar Observatory to Manage Their Farming

Stone causeway atop Mount Tlaloc, Mexico. Credit: Ben Messiner/UCR

Pre-Columbian Mexico (or Mesoamerica) hosted one of the largest civilizations and populations in the world. The most well-known and dominant of these civilizations (prior to the arrival of the Conquistadors) were the Aztecs (or Mexica). Their empire, known as the Triple Alliance, was centered around Lake Texcoco and consisted of the major cities Tenochtitlan, Texcoco, and Tlacopan. In addition to engineering massive temples, aqueducts, canal systems, and estuaries, the Aztecs are renowned for being accomplished astronomers and agronomists.

At the height of their power, the Aztec Empire supported a population of up to 3 million in the Valley of Mexico, and many of their largest cities had populations exceeding 100,000. This was not easy, given that the region is characterized by arid springs followed by winter monsoons. According to recent research by the University of California Riverside (UCR), the Aztecs used mountain alignments as a solar observatory to create an accurate agricultural calendar. This allowed their farmers to produce enough food to feed one of the most densely-populated regions on Earth.

December 15, 2022December 15, 2022 by Alan Boyle

Avatars Return to the Movies — and Find a Real-Life Foothold

In the form of a Na'vi avatar, Jake Sully rides an alien flying fish in "Avatar: The Way of Water." (20th Century Studios)

Thirteen years after the original “Avatar” movie came out, the idea of human minds inhabiting alien bodies is returning for an amped-up sequel — and since 2009, real-life efforts to create robotic avatars have advanced at least as much as computer-aided filmmaking has.

Oscar-winning director James Cameron’s “Avatar: The Way of Water” returns to Pandora, a far-off exomoon where the peaceful, blue-skinned Na’vi people are menaced by human invaders who are capable of getting into their skin. The film is a visual mind-blower, combining elements of underwater documentaries, video games and the movie that earned Cameron his Oscar: “Titanic.”

The idea of a human taking charge of an alien body via virtual reality is pure science fiction — but if you replace the fictional Na’vi with a robot, you get the premise for the ANA Avatar XPRIZE, which gave out its top awards at the $10 million competition’s finals in November.

In the latest episode of the Fiction Science podcast, we focus on the parallels between the science-fiction vision embodied in the Avatar movies and the future-tech vision that roboticists are pursuing through the Avatar XPRIZE and other efforts. Someday, robotic avatars could well transform space exploration as well as life back here on Earth.

December 14, 2022December 14, 2022 by Brian Koberlein

The Formation of the Southern Ring Nebula was Messier Than the Death of a Single Star

JWST images of the Southern Ring Nebula as seen from the telescope's NIRCam (left) and MIRI (right). Credit: NASA, ESA, CSA, and STScI

Two thousand five hundred years ago, during the height of the bronze age, an old red star died. Its outer layers expanded over time, becoming what is now known as the Southern Ring Nebula, or less romantically, NGC 3132. By the looks of it, this planetary nebula looks like many others. As Sun-like stars die, they swell to become red giants before becoming a white dwarf, and their outer layers typically become a planetary nebula. But a recent study finds that this particular nebula formed in a way quite messier than we had thought.

December 13, 2022December 13, 2022 by Evan Gough

Hubble Sees a Glittering Jewel in the Small Magellanic Cloud. But the Jewel is Disappearing

A small portion of the Small Magellanic Cloud (SMC) is pictured in this image from the NASA/ESA Hubble Space Telescope. Image Credit: NASA/ESA

As far as we know, nobody lives in our neighbour, the Small Magellanic Cloud (SMC.) So it’s okay to point our telescope there and gaze at it.

December 13, 2022December 13, 2022 by Matt Williams

Astronomers Spot Three Interacting Systems with Twin Discs

Artist's conceptualization of the dusty TYC 8241 2652 system as it might have appeared several years ago when it was emitting large amounts of excess infrared radiation. Credit: Gemini Observatory/AURA artwork by Lynette Cook. https://www.gemini.edu/node/11836

According to the most widely-accepted theory about star formation (Nebular Hypothesis), stars and planets form from huge clouds of dust and gas. These clouds undergo gravitational collapse at their center, leading to the birth of new stars, while the rest of the material forms disks around it. Over time, these disks become ring structures that accrete to form systems of planets, planetoids, asteroid belts, and Kuiper belts. For some time, astronomers have questioned how interactions between early stellar environments may affect their formation and evolution.

For instance, it has been theorized that gravitational interactions with a passing star or shock waves from a supernova might have triggered the core collapse that led to our Sun. To investigate this possibility, an international team of astronomers observed three interacting twin disc systems using the Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE) on the ESO’s Very Large Telescope (VLT). Their findings show that due to their dense stellar environments, gravitational encounters between early-stage star systems play a significant role in their evolution.