Universe Today

August 29, 2024August 31, 2024 by Matt Williams

Remember those Impossible Galaxies Found by JWST? It Turns Out They Were Possible After All

This is a small portion of the field observed by NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) for the Cosmic Evolution Early Release Science (CEERS) survey. It is filled with galaxies. The light from some of them has traveled for over 13 billion years to reach the telescope. Credit: NASA, ESA, CSA, Steve Finkelstein (University of Texas at Austin)

When the James Webb Space Telescope provided astronomers with a glimpse of the earliest galaxies in the Universe, there was some understandable confusion. Given that these galaxies existed during “Cosmic Dawn,” less than one billion years after the Big Bang, they seemed “impossibly large” for their age. According to the most widely accepted cosmological model—the Lambda Cold Dark Matter (LCDM) model—the first galaxies in the Universe did not have enough time to become so massive and should have been more modestly sized.

This presented astronomers with another “crisis in cosmology,” suggesting that the predominant model about the origins and evolution of the Universe was wrong. However, according to a new study by an international team of astronomers, these galaxies are not so “impossibly large” after all, and what we saw may have been the result of an optical illusion. In short, the presence of black holes in some of these early galaxies made them appear much brighter and larger than they actually were. This is good news for astronomers and cosmologists who like the LCDM the way it is!

August 29, 2024August 29, 2024 by Mark Thompson

For Their Next Trick, Gravitational Wave Observatories Could Detect Collapsing Stars

After the death of a massive, spinning star, a disk of material forms around the central black hole. As the material cools and falls into the black hole, new research suggests that detectable gravitational waves are created. Ore Gottlieb

The merging of black holes and neutron stars are among the most energetic events in the universe. Not only do they emit colossal amounts of energy, they can also be detected through gravitational waves. Observatories like LIGO/Virgo (Laser Interferometer Gravitational Wave Observatory) and KAGRA (The Kamioka Gravitational Wave Detector) have detected their gravitational waves but new gravitational wave observatories are now thought to be able to detect the collapse of a massive rapidly spinning star before it becomes a black hole. According to new research, collapsing stars within 50 million light years should be detectable.

August 29, 2024August 29, 2024 by Mark Thompson

Giant Low-Frequency Scan Searches for Aliens in 2,800 Galaxies

One of the tiles making up the 32T, a prototype instrument for the Murchison Widefield Array. Natasha Hurley-Walker

The search for extraterrestrial intelligence (SETI) has fascinated us for decades. Now a team of researchers have used the Murchison Widefield Array in Australia to scan great swathes of sky for alien signals. Unusually for a SETI project, this one focussed attention on 2,800 galaxies instead of stars within our own. They have been on the lookout for advanced civilisations that are broadcasting their existence using the power of an entire star. Alas they weren’t successful but its an exciting new way to search for alien intelligence.

August 29, 2024August 29, 2024 by Nancy Atkinson

NASA's New Solar Sail Extends Its Booms and Sets Sail

An artist's concept of NASA's Advanced Composite Solar Sail System spacecraft in orbit as the Sun crests Earth's horizon. Credits: NASA/Aero Animation/Ben Schweighart

Solar sails are an exciting way to travel through the Solar System because they get their propulsion from the Sun. NASA has developed several solar sails, and their newest, the Advanced Composite Solar Sail System (or ACS3), launched a few months ago into low-Earth orbit. After testing, NASA reported today that they extended the booms, deploying its 80-square-meter (860 square feet) solar sail. They’ll now use the sail to raise and lower the spacecraft’s orbit, learning more about solar sailing.

“The Sun will continue burning for billions of years, so we have a limitless source of propulsion. Instead of launching massive fuel tanks for future missions, we can launch larger sails that use ‘fuel’ already available,” said Alan Rhodes, the mission’s lead systems engineer at NASA’s Ames Research Center, earlier this year. “We will demonstrate a system that uses this abundant resource to take those next giant steps in exploration and science.”

August 29, 2024August 29, 2024 by Matt Williams

Webb Discovers Six New “Rogue Worlds” that Provide Clues to Star Formation

This stunning new mosaic of images from the NASA/ESA/CSA James Webb Space Telescope showcases the nearby star-forming cluster, NGC 1333. Credit: ESA/Webb, NASA & CSA, A. Scholz, K. Muzic, A. Langeveld, R. Jayawardhana

Rogue Planets, or free-floating planetary-mass objects (FFPMOs), are planet-sized objects that either formed in interstellar space or were part of a planetary system before gravitational perturbations kicked them out. Since they were first observed in 2000, astronomers have detected hundreds of candidates that are untethered to any particular star and float through the interstellar medium (ISM) of our galaxy. In fact, some scientists estimate that there could be as many as 2 trillion rogue planets (or more!) wandering through the Milky Way alone.

In recent news, a team of astronomers working with the James Webb Space Telescope (JWST) announced the discovery of six rogue planet candidates in an unlikely spot. The planets, which include the lightest rogue planet ever identified (with a debris disk around it), were spotted during Webb‘s deepest survey of the young nebula NGC 1333, a star-forming cluster about a thousand light-years away in the Perseus constellation. These planets could teach astronomers a great deal about the formation process of stars and planets.

August 29, 2024August 29, 2024 by Evan Gough

A NASA Rocket Has Finally Found Earth’s Global Electric Field

NASA's Endurance Rocket lifts off from Svalbard in 2022. The results are in and the rocket successfully measured Earth's global electric field. Image Credit: NASA/Brian Bonsteel

Scientists have discovered that Earth has a third field. We all know about the Earth’s magnetic field. And we all know about Earth’s gravity field, though we usually just call it gravity.

Now, a team of international scientists have found Earth’s global electric field.

August 29, 2024August 29, 2024 by Andy Tomaswick

What Type of Excavator Is Most Suitable for Asteroids?

Digging in the ground is so commonplace on Earth that we hardly ever think of it as hard. But doing so in space is an entirely different proposition. On some larger worlds, like the Moon or Mars, it would be broadly similar to how digging is done on Earth. But their “milligravity” would make the digging experience quite different on the millions of asteroids in our solar system. Given the potential economic impact of asteroid mining, there have been plenty of suggested methods on how to dig on an asteroid, and a team from the University of Arizona recently published the latest in a series of papers about using a customized bucket wheel to do so.

August 29, 2024August 29, 2024 by Evan Gough

The Rubin Observatory Will Unleash a Flood of NEO Detections

The Vera Rubin Observatory is poised to begin observations next year. It could detect 130 Near Earth Objects each night. Image Credit: Rubin Observatory/NSF/AURA/B. Quint

After about 10 years of construction, the Vera Rubin Observatory (VRO) is scheduled to see its first light in January 2025. Once it’s up and running, it will begin its Legacy Survey of Space and Time (LSST), a decade-long effort to photograph the entire visible sky every few nights. It’ll study dark energy and dark matter, map the Milky Way, and detect transient astronomical events and small Solar System objects like Near Earth Objects (NEOs).

New research shows the LSST will detect about 130 NEOs per night in the first year of observations.

August 28, 2024August 28, 2024 by Carolyn Collins Petersen

What if you Flew Your Warp Drive Spaceship into a Black Hole?

Dall-E image of a ship with warp drive entering a black hole. Courtesy Fraser Cain.

Warp drives have a long history of not existing, despite their ubiquitous presence in science fiction. Writer John Campbell first introduced the idea in a science fiction novel called Islands of Space. These days, thanks to Star Trek in particular, the term is very familiar. It’s almost a generic reference for superliminal travel through hyperspace. Whether or not warp drive will ever exist is a physics problem that researchers are still trying to solve, but for now, it’s theoretical.

August 28, 2024August 28, 2024 by Evan Gough

DART Did More Than Deter Dimorphos; It Sent It Into a Chaotic Tumble

Artist's impression of the DART mission approaching the double-asteroid Didymos and its moon Dimorphos. Credit: NASA

In 2022, NASA’s DART (Double Asteroid Redirection Test) spacecraft collided with an object named Dimorphos. The objective was to test redirecting hazardous asteroids by deflecting them with an impact. The test was a success, and Dimorphos was measurably affected.

Follow-up research shows that Dimorphos was more than deflected; it was deformed.