Universe Today

December 4, 2024December 4, 2024 by Evan Gough

Here’s How Interstellar Objects and Rogue Planets Can be Trapped in the Solar System

Illustration of an interstellar object approaching our solar system. Credit: Rubin Observatory/NOIRLab/NSF/AURA/J. daSilva

When Oumuamua traversed our Solar System in 2017 it was the first confirmed Interstellar Object (ISO) to do so. Then in 2019, Comet 2l/Borisov did the same thing. These are the only two confirmed ISOs to visit our Solar System. Many more ISOs must have visited in our Solar System’s long history, and many more will visit in the future. There are obviously more of these objects out there, and the upcoming Vera Rubin Observatory is expected to discover many more.

It’s possible that the Sun could capture an ISO or a rogue planet in the same way that some of the planets have captured moons.

It all comes down to phase space.

December 4, 2024December 5, 2024 by Brian Koberlein

MeerKAT Confirms the Gravitational Wave Background of the Universe in Record Time

A MeerKAT antenna disk in front of an illustrated view of black holes and gravitational waves. Credit: Carl Knox, OzGrav, Swinburne University of Technology and South African Radio Astronomy Observatory

The Universe is a turbulent place. Stars are exploding, neutron stars collide, and supermassive black holes are merging. All of these things and many more create gravitational waves. As a result, the cosmos is filled with a rippling sea of gravitational vibrations. While we have been able to directly detect gravitational waves since 2016, gravitational wave astronomy is still in its infancy. We have only been able to observe the gravitational ripples of colliding stellar black holes. Even then, all we can really detect is the final gravitational chirp created in the last moments of merging.

December 4, 2024December 4, 2024 by Andy Tomaswick

Could We Use An Asteroid to Shield Astronauts On Their Way to Mars?

Illustration of the asteroid Bennu. Credit: NASA Jet Propulsion Laboratory

Radiation is a primary concern for long-duration human spaceflight, such as the planned trips to Mars, which are the stated goal of organizations such as NASA and SpaceX. Shielding is the standard way to protect astronauts from radiation during those flights. However, shielding is heavy and, therefore, expensive when it is launched off the Earth. What if, instead, astronauts could hitch a ride on a giant mass of shielding already in space that will take them directly to their destination? That is the basic thought behind a paper from Victor Reshetnyk and his student at Taras Shevchenko National University in Kyiv.

December 4, 2024December 4, 2024 by Brian Koberlein

Maybe Venus Was Never Habitable

Earth and Venus. Why are they so different and what do the differences tell us about rocky exoplanet habitability? Image Credit: NASA

Although they are very different today, Venus, Earth, and Mars were very similar in their youth. All three were warm, with thick, water-rich atmospheres. But over time, Mars became a cold, dry planet with a thin atmosphere, and Venus became superheated, with a crushing, toxic sky. Only Earth became a warm ocean world teeming with life. But why?

December 3, 2024December 3, 2024 by Laurence Tognetti

Astronauts on Long Missions Will Need Personal AI Assistants

Astronaut Megan McArthur uses a HoloLens head-mounted display (HMD) during Expedition 65 onboard the International Space Station. (Credit: NASA)

How can artificial intelligence (AI) help astronauts on long-term space missions? This is what a recent study presented at the 2024 International Astronautical Congress in Milan, Italy, hopes to address as an international team of researchers led by the German Aerospace Center introduce enhancements for the Mars Exploration Telemetry-Driven Information System (METIS) system and how this could help future astronauts on Mars mitigate the communications issues between Earth and Mars, which can take up to 24 minutes depending in the orbits. This study holds the potential to develop more efficient technology for long-term space missions beyond Earth, specifically to the Moon and Mars.

December 3, 2024December 3, 2024 by Evan Gough

Could Primordial Black Holes Be Hiding in Plain Sight?

An artistic take on primordial black holes. Credit: NASA’s Goddard Space Flight Center

Are Primordial Black Holes real? They could’ve formed in the unusual physics that dominated the Universe shortly after the Big Bang. The idea dates back to the 1960s, but so far, the lack of evidence makes them purely hypothetical.

If they do exist, a new paper suggests they may be hiding in places so unlikely that nobody ever thought to look there.

December 3, 2024December 3, 2024 by Andy Tomaswick

NASA Wants Students’ Help Designing Missions to Other Moons

One of NASA’s primary missions is to inspire the next generation of scientists and engineers to join the STEM field. It does so by producing inspirational and educational content on various platforms. But sometimes, it takes a more direct approach by rewarding students for their contributions to solving a particular problem NASA is facing. Recently, the organization announced such a challenge – the Power to Explore Challenge, which is open to submission from K-12 students until the end of January.

December 3, 2024December 3, 2024 by Evan Gough

Antarctica Has Gotten 10 Times Greener in 35 Years

Antarctica is becoming greener due to climate change. Image Credit: Michala Garrison, based on data from Roland, T.P., et al. (2024).

Our satellites are dispassionate observers of Earth’s climate change. From their vantage point they watch as pack ice slowly loses its hold on polar oceans, ice shelfs break apart, and previously frozen parts of the planet turn green with vegetation.

Now, scientists have compiled 35 years of satellite data showing that Antarctica is slowly, yet perceptibly, becoming greener.

December 3, 2024December 3, 2024 by Brian Koberlein

White Dwarfs Could Have Habitable Planets, Detectable by JWST

An Earth-sized remnant of a Sun-like star is ringed by dust and debris. Credit: NASA’s Goddard Space Flight Center/Scott Wiessinger

In a few billion years, our Sun will die. It will first enter a red giant stage, swelling in size to perhaps the orbit of Earth. Its outer layers will be cast off into space, while its core settles to become a white dwarf. Life on Earth will boil away, and our planet itself might be consumed by the Sun. White dwarfs are the fate of all midsize stars, and given the path of their demise, it seems reasonable to assume that any planets die with their sun. But the fate of white dwarf planets may not be lifeless after all.

December 3, 2024December 3, 2024 by David Dickinson

Catch Jupiter at Opposition 2024 This Coming Weekend

Now is the time to catch Jupiter at its best.

The King of the Planets rules the winter night skies. Early December gives sky watchers a good reason to brave the cold, as Jupiter shines at its best. Look for the regal planet rising in the east at sunset, while the Sun sets to the west.