Universe Today

August 17, 2023August 17, 2023 by Brian Koberlein

We Might Be Able to Measure Dark Energy Through the Milky Way's Collision With Andromeda

How the sky might look when the Andromeda galaxy approaches the Milky Way. Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger

The Universe is expanding, and it’s doing so at an ever-increasing pace. Whether due to a dark energy field throughout the cosmos or due to a fundamental of spacetime itself, the cosmos is stretching the space between distant galaxies. But nearby galaxies, those part of our local group, are moving closer together. And how they are falling toward each other could tell us about the nature of cosmic expansion.

August 17, 2023August 17, 2023 by Nancy Atkinson

This Brown Dwarf is 2,000 Degrees Hotter Than the Sun

exoplanet hot jupiter transiting its star — This artist’s impression shows an ultra-hot exoplanet as it is about to transit in front of its host star. Credit: ESO

Astronomers have discovered an intense binary star system located about 1,400 light years away. It contains a brown dwarf with 80 times the mass of Jupiter which is bound closely with an incredibly hot white dwarf star. Observations have shown the brown dwarf is tidally locked to the white dwarf, allowing the daytime surface temperatures on the brown dwarf to reach 8,000 Kelvin (7,700 Celsius, 14,000 Fahrenheit) — which is much hotter than the surface of the Sun, which is about 5,700 K (5,427 C, 9,800 F). The brown dwarf’s nightside, on the other hand, is about 6,000 degrees K cooler.

August 16, 2023August 16, 2023 by Evan Gough

The Sun Gets Meteor Showers Too, But They’re Very Different

SolO view in the EUV on 30 March 2022 showing a partial section of the Sun with gas at 1 million degrees. Credit Patrick Antolin. Background image: ESA/Solar Orbiter EUI/HRI Licence type Attribution (CC BY 4.0)

The Sun dominates the Solar System in almost every way imaginable, yet much of its inner workings have been hidden from humanity. Over the centuries, and especially in the last few decades, technological advancements allowed us to ignore our mothers’ exhortations and stare at the Sun for as long as we want. We’ve learned a lot from all those observations.

A new study shows how the Sun experiences its own ‘meteor showers.’

August 16, 2023August 16, 2023 by Brian Koberlein

New Horizons is So Far Away, it Can Measure the True Darkness of the Universe

Artist view of the New Horizons spacecraft against a sea of stars. Credit: Serge Brunier/Marc Postman/Dan Durda

Just how dark is the night sky?

If you step outside during a moonless night and look up, it probably doesn’t look that dark at all. Streetlights or nearby porch lights fill the air with a background glow, particularly if they happen to be bluish-white LEDs. Light pollution in your neighborhood is likely so bad that you can only see a few bright stars. Even in somewhat rural areas, our skies are so bright that the Milky Way isn’t really visible. In North America and Europe, only about a quarter of children have seen the Milky Way.

August 16, 2023August 16, 2023 by Matt Williams

You’re Looking at One of the Farthest Confirmed Galaxies Found by JWST

Scientists with the CEERS Collaboration have identified an object (Maisie’s galaxy) that may be one of the earliest and farthest galaxies ever observed. Credit: NASA/STScI/CEERS/TACC/S. Finkelstein/M. Bagley/Z. Levay.

One of the main objectives of the James Webb Space Telescope (JWST) is to use its powerful optics and advanced instruments to observe the earliest galaxies in the Universe. These galaxies formed about 1 billion years after the Big Bang, coinciding with the end of what is known as the “Cosmic Dark Ages.” This epoch is inaccessible for conventional optical telescopes because the only sources of photons were largely associated with the relic radiation of the Big Bang – visible today as the Cosmic Microwave Background (CMB) – or were the result of the reionization of neutral hydrogen (visible today the 21 cm line).

Thanks to its advanced optics and infrared imaging capabilities, Webb has pushed the boundaries of how far astronomers and cosmologists can see. One of the most interesting finds was Maisie’s galaxy, which appeared to have existed roughly 390 million years after the Big Bang. According to a new study by the Cosmic Evolution Early Release Science Survey (CEERS) that recently appeared in Nature, these results have since been confirmed. This makes Maisie’s galaxy one of the farthest (and earliest) confirmed galaxies ever observed by human eyes.

August 15, 2023August 15, 2023 by Carolyn Collins Petersen

We’ve Never Seen Antarctic Sea Ice This Low

A map showing the expected amount of sea ice accumulation around Antarctica (yellow line) and the reality, which is much less. Courtesy NSIDC.

While many people are living through a sweltering summer, it’s the depths of winter in Antarctica. Usually, this means there’s a lot of sea ice around the continent. Yet, this year, it’s the lowest it’s ever been. What’s happening?

August 15, 2023August 21, 2023 by Matt Williams

The 2nd Annual Penn State SETI Symposium and the Search for Technosignatures!

Artist's impression of a Dyson Sphere, an proposed alien megastructure that is the target of SETI surveys. Finding one of these qualifies in a "first contact" scenario. Credit: Breakthrough Listen / Danielle Futselaar

From June 18th to 22nd, the Penn State Extraterrestrial Intelligence Center (PSETI) held the second annual Penn State SETI Symposium. The event saw experts from many fields and backgrounds gathering to discuss the enduring questions about SETI, the technical challenges of looking for technosignatures, its ethical and moral dimensions, and what some of the latest experiments have revealed. Some very interesting presentations examined what will be possible in the near future and the likelihood that we will find evidence of extraterrestrial intelligence.

Among them, there were some very interesting presentations by Adam Frank, Professor of Astrophysics at the University of Rochester; Ph.D. student Matias Suazo, an astrophysicist and member of Project Haephestos at the University of Uppsala; and Nicholas Siegler, the Chief Technologist of NASA’s Exoplanet Exploration Program (ExEP). These presentations addressed ongoing issues in the search for extraterrestrial intelligence (ETI), technosignatures, the role of oxygen in the evolution of complex life, and what motivations extraterrestrial civilizations (ETC) might have for creating noticeable signatures.

August 15, 2023August 15, 2023 by Andy Tomaswick

A Robot With Expandable Appendages Could Explore Martian Caves And Cliffs

Plenty of areas in the solar system are interesting for scientific purposes but hard to access by traditional rovers. Some of the most prominent are the caves and cliffs of Mars – where exposed strata could hold clues to whether life ever existed on the Red Planet. So far, none of the missions sent there has been able to explore those difficult-to-reach places. But a mission concept from a team at Stanford hopes to change that.

August 14, 2023August 14, 2023 by Matt Williams

New Muon g-2 Result Improves the Measurement by a Factor of 2

First results from the Muon g-2 experiment at Fermilab have strengthened evidence of new physics. Credit: Reidar Hahn/Fermilab

At the Fermi National Accelerator Laboratory (aka. Fermilab), an international team of scientists is conducting some of the most sensitive tests of the Standard Model of Particle Physics. The experiment, known as Muon g-2, measures the anomalous magnetic dipole moment of muons, a fundamental particle that is negatively charged (like electrons) but over 200 times as massive. In a recent breakthrough, scientists at Fermilab made the world’s most precise measurement of the muon’s anomalous magnetic moment, improving the precision of their previous measurements by a factor of 2.

August 14, 2023August 14, 2023 by Brian Koberlein

Storms on Saturn Can Have Impacts That Last for Hundreds of Years

A giant storm rages on Saturn. Credit: NASA/JPL-Caltech/SSI

The Great Red Spot of Jupiter is a storm that has raged for hundreds of years. It was first observed by Gian Domenico Cassini in 1665, and except for a period between 1713 to 1830, it has been observed continuously ever since. Even if Cassini’s storm is not the one we see today, the current red spot has been around for nearly two centuries. While great storms appear now and then on Saturn and other gas planets, they don’t have the staying power of Jupiter’s great storm. Or so we thought.