Universe Today

October 2, 2024October 7, 2024 by Nancy Atkinson

NASA Turns Off One of Voyager 2's Science Instruments

Voyager 2. Credit: NASA — Artist's impression of the Voyager 2 space probe. Credit: NASA

The two Voyager spacecraft have been speeding through space since 1977, powered by decaying chunks of plutonium that produce less and less energy every year. With less electricity available, NASA has decided to shut down one experiment on Voyager 2, the plasma science instrument. This device measures the quantity and direction of ionized particles passing the spacecraft. While Voyager 2 still has enough electricity to support its four other operational instruments, it will likely be down to just one by the 2030s.

October 2, 2024October 2, 2024 by Brian Koberlein

Bernard's Star Has a Planet (Again)!

This artist’s impression shows Barnard b, a sub-Earth-mass planet that was discovered orbiting Barnard’s star. Credit: ESO/M. Kornmesser

The thing about exoplanets is that astronomers don’t see them the way most people think they do. Part of the reason for that is the way we announce them. Whenever an interesting exoplanet is discovered, the press release usually has colorful artwork showing oceans, mountains, and clouds. Something visually captivating like the image above. But the reality is that we have only imaged a few exoplanets directly, and even then, they appear only as small fuzzy blobs. Most of the known exoplanets were discovered by the transit method, where the star dims slightly as the planet passes in front of it. So what astronomers actually see is a periodic flickering of starlight.

October 1, 2024October 2, 2024 by Matt Williams

An Earth-like Planet Around a Dead Sun Provides Some Reassurance About the Future of Earth

Astronomers have discovered a distant white dwarf with an Earth-like planet in an orbit just beyond where Mars is in our solar system. Earth could end up in such an orbit circling a white dwarf in about 8 billion years, if, like this exoplanet, it can survive the sun's red giant phase on its way to becoming a white dwarf. Credit: Adam Makarenko

In about five billion years, our Sun will exit its main sequence phase and transition to its red giant phase. At this point, the Sun will expand and consume the planets of the inner Solar System, including Mercury and Venus. What will become of Earth when this happens has been the subject of debate for many decades. But with the recent explosion in exoplanet discoveries, 5,759 confirmed in 4,305 systems so far, astronomers hope to learn more about how planets fare as their stars near the end of their life cycle.

Using the 10-meter telescope at the Keck Observatory in Hawaii, an international team of astronomers discovered an Earth-like planet orbiting a white dwarf star 4,000 light-years from Earth. This planet orbits its star, about half the mass of our Sun, at a distance roughly twice that of the Earth today. The system resembles what is expected to become of our system once the Sun has exhausted the last of its fuel and sheds its outer layers. It also offers some assurances that Earth will survive the Sun becoming a red giant and exploding in a supernova.

October 1, 2024October 1, 2024 by Laurence Tognetti

We Don’t See Many Planets in Old Triple Star Systems

Example of a triple star system. (Credit: Caltech/R. Hurt (Infrared Processing and Analysis Center, or IPAC)

Why is it important to search for exoplanets in triple star systems and how many can we find there? This is what a recent study accepted by Astrophysics & Space Science hopes to address as a pair of researchers from the University of Texas at Arlington investigated the statistical likelihood of triple star systems hosting exoplanets. This study holds the potential to help researchers better understand the formation and evolution of triple star systems and whether they are suitable to find life as we know it.

September 30, 2024October 3, 2024 by Carolyn Collins Petersen

Perseverance Finds a Strange Black-and-White Striped Rock on Mars

Mars Perseverance Rover's September 13, 2024 view of Freya Castle, a strange-looking striped rock in Jezero Crater. Credit: NASA/JPL-Caltech/ASU

The hits just keep on coming from the Mars Perseverance rover. It’s exploring Jezero Crater on the Red Planet, looking for evidence of microbial life in the planet’s ancient (or even recent) past. Recently it spotted a very strange-looking rock with black and white stripes. Its appearance and location sparked a lot of questions. Perseverance team members have named it “Freya Castle.”

September 30, 2024September 30, 2024 by Mark Thompson

Was the Moon Captured?

The general consensus is that Theia crashed into Earth billions of years ago and led to the formation of the Moon. The story doesn’t end there though since there are a few lines of evidence to suggest the Moon could have been captured by the gravitational pull of the Earth instead. The orbit of the Moon is one such observation that leads to a different conclusion for it’s in-line with the plane of the ecliptic rather than the Earth’s equator. A team of researchers have suggested capture theory was the Moon’s origin.

September 30, 2024September 30, 2024 by Matt Williams

The ESO Releases the Most Detailed Infrared Map of our Galaxy Ever Made

This collage highlights a small selection of regions of the Milky Way imaged as part of the most detailed infrared map ever of our galaxy. Here we see, from left to right and top to bottom: NGC 3576, NGC 6357, Messier 17, NGC 6188, Messier 22 and NGC 3603. All of them are clouds of gas and dust where stars are forming, except Messier 22, which is a very dense group of old stars. The images were captured with ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA) and its infrared camera VIRCAM. The gigantic map to which these images belong contains 1.5 billion objects. The data were gathered over the course of 13 years as part of the VISTA Variables in the Vía Láctea (VVV) survey and its companion project, the VVV eXtended survey (VVVX).

Despite decades of large-scale optical surveys, there are still mysteries about the Milky Way galaxy that astronomers are eager to resolve. This is particularly true of its internal structure and the core region, which is difficult to survey due to clouds of gas and dust in the interstellar medium (ISM). This material absorbs visible light, making fainter objects difficult to see in optical wavelengths. Luckily, advances in infrared astronomy have enabled surveys of the Milky Way that have revealed things that would otherwise remain invisible to us.

For more than 13 years, an international team of astronomers has been observing the Milky Way using the ESO’s 4.1-meter Visible and Infrared Survey Telescope for Astronomy (VISTA). In a recently published study, they announced the release of their final data product: a gigantic infrared map of the Milky Way containing more than 1.5 billion objects—the most detailed map our galaxy has ever created! With over 200,000 images and 500 terabytes of data, this map is also the largest observational project ever carried out with an ESO telescope.

September 30, 2024September 30, 2024 by Mark Thompson

Stranded Astronauts To Get Their Ride Home

You might remember the story of the two astronauts on board the International Space Station that went for an 8 day mission, that was back in June 2024! Butch Wilmore and Suni Williams have been stranded there ever since but their ride home has just arrived at the ISS. A SpaceX Crew Dragon capsule carrying Nick Hague and Aleksandr Gorbunov has just docked so that the two can join the Expedition 72 crew already on board. There are now 11 people on boar the ISS but the Crew-9 capsule will return in February carrying Wilmore and Williams finally back home.

September 30, 2024October 2, 2024 by David Dickinson

An October Annular Solar Eclipse Rounds Out 2024

A remote annular solar eclipse bookends the final eclipse season for 2024.

The final eclipse of the year is almost upon us. If skies are clear, a few lucky observers and intrepid eclipse-chasers will get to witness the passage of the Moon in front of the Sun one last time on Wednesday, October 2^nd during an annular solar eclipse.

September 30, 2024September 30, 2024 by Mark Thompson

Nuclear Detonations Could Deflect Dangerous Asteroids Away from Earth

Before you read the rest of this article know there are no known threats to life on Earth! We shouldn’t sit complacently on this tiny rock in space though so NASA have been working on ways to neutralise potential asteroid threats should they arise. The DART mission proved it was possible to alter the trajectory of an asteroid in space. Direct impact though where a probe smashes into the rock is one way but potentially not the best. A team of researchers have now been exploring ways that a nuclear explosion near an asteroid may send a blast of X-rays sufficiently powerful to vaporise material generating thrust to redirect the asteroid.