Universe Today

November 25, 2024November 25, 2024 by Brian Koberlein

Einstein Predicted How Gravity Should Work at the Largest Scales. And He Was Right

The sparkling band of the Milky Way Galaxy backdrops the Nicholas U. Mayall 4-meter Telescope, located at Kitt Peak National Observatory. Credit: KPNO/NOIRLab/NSF/AURA/R.T. Sparks

When Albert Einstein introduced his theory of general relativity in 1915, it changed the way we viewed the Universe. His gravitational model showed how Newtonian gravity, which had dominated astronomy and physics for more than three centuries, was merely an approximation of a more subtle and elegant model. Einstein showed us that gravity is not a mere force but is rather the foundation of cosmic structure. Gravity, Einstein said, defined the structure of space and time itself.

November 25, 2024November 25, 2024 by David Dickinson

Watch the Crescent Moon Occult Spica for North America Early Wednesday Morning

One of the best bright star lunar occultations for 2024 occurs this week, as the Moon covers Spica.

Have you ever seen the Moon blot out a star? If the weather cooperates, early morning viewers across eastern North America have a chance to see a rare spectacle, as the crescent Moon occults (covers) the bright star Spica.

November 25, 2024November 25, 2024 by Mark Thompson

NASA Releases its Moon Phases Animation for 2025

Every year, NASA releases a detailed simulation of the Moon that shows how it will change through the year. They produce a couple of versions that show how it appears from the northern and southern hemisphere and others that highlight different features. Not only does it show the phases through the year but it also shows the change in size as its completes its orbit. The change in apparent size of the Moon is a result of its elliptical orbit so that it can appear up to 30% brighter.

November 25, 2024November 24, 2024 by Matt Williams

NASA, SpaceX Illustrate Key Moments of Artemis Lunar Lander Mission

Artist's rendering of the Starship HLS on the lunar surface. NASA has contracted with SpaceX to provide the lunar landing system. Credit: SpaceX — Artist's rendering of the Starship HLS on the Moon's surface. NASA has contracted with SpaceX to provide the lunar landing system. Credit: SpaceX

Before the decade is out, as part of the Artemis Program, NASA plans to send astronauts to the Moon for the first time since the Apollo Era. To realize this goal, they have contracted with commercial space industries to develop all the necessary components. This includes the Space Launch System (SLS) and the Orion spacecraft that will take the Artemis astronauts to the Moon. There’s also the Lunar Gateway and the Artemis Base Camp, the infrastructure that will facilitate regular missions to the Moon after 2028.

In between, NASA has also partnered with companies to develop the Human Landing Systems (HLS) that will transport the Artemis astronauts to the lunar surface and back. This includes the Starship HLS SpaceX is currently developing for NASA, which will rendezvous with the Orion spacecraft in lunar orbit and allow the Artemis III astronauts to land on the Moon (which will take place no sooner than September 2026). In a series of newly-updated images, SpaceX has provided artistic renders of what key moments in this mission will look like.

November 24, 2024November 24, 2024 by Matt Williams

The Last Arecibo Message Celebrates the Observatory and One of its Greatest Accomplishments

The Arecibo radio telescope in Puerto Rico. (Seth Shostak/SETI Institute/Associated Press)

The Arecibo Message, transmitted on November 16th, 1974, from the Arecibo Observatory, was humanity’s first true attempt at Messaging Extraterrestrial Intelligence (METI). The message was a simple pictorial signal in binary code composed by famed astronomer and SETI researcher Frank Drake (inventor of the Drake Equation) with the assistance of Sagan and other prominent astronomers. The message was and was aimed toward Messier 13 (NGC 6205 or “The Great Hercules Cluster”), a globular star cluster located about 25,000 light-years from Earth in the constellation of Hercules.

In 2018, in preparation for the 45th anniversary of the historic broadcast, the Arecibo Message Global Challenge was launched. Student teams were tasked with designing a new message that could be sent to space, and by August 2020, the Boriken Voyagers team was recognized as the winner of the competition. Unfortunately, the Observatory collapsed on December 1st, 2020, and the message was never sent. To commemorate the 50th anniversary of the Arecibo Message, the Boriken Voyagers have shared “The Last Arecibo Message.”

November 24, 2024December 7, 2024 by Matt Williams

A Nearby Supernova Could Finally Reveal Dark Matter

SN 1987a as seen by JWST's Near-Infrared Camera. Credit: NASA, ESA, CSA, M. Matsuura, R. Arendt, C. Fransson

Despite 90 years of research, the nature and influence of Dark Matter continue to elude astronomers and cosmologists. First proposed in the 1960s to explain the rotational curves of galaxies, this invisible mass does not interact with normal matter (except through gravity) and accounts for 85% of the total mass in the Universe. It is also a vital component in the most widely accepted cosmological model of the Universe, the Lambda Cold Dark Matter (LCDM) model. However, according to new research, the hunt for DM could be over as soon as a nearby star goes supernova.

Currently, the axion is considered the most likely candidate for DM, a hypothetical low-mass particle proposed in the 1970s to resolve problems in quantum theory. There has also been considerable research into how astronomers could detect axions by observing neutron stars and objects with powerful magnetic fields. In a recent study supported by the U.S. Department of Energy, a team of astrophysicists at the University of California Berkeley argued that axions could be discovered within seconds of detecting gamma rays from a nearby supernova explosion.

November 23, 2024November 23, 2024 by Scott Alan Johnston

Astronomers Find a 3 Million Year Old Planet

An artistic interpretation of the IRAS 04125+2902 (TIDYE-1) system. Young stars like this are covered in starspots—regions cooler than the surrounding stellar surface. The inner disk is depleted, leaving an intact outer disk that forms a donut-like structure around the host star. The outer disk is nearly face-on, in contrast to the edge-on planet orbit around the host star. This allows for an unobstructed view of the system. If the disk were also edge-on, it would block the planet and host star, preventing the discovery. Credit: NASA/JPL-Caltech/R. Hurt, K. Miller (Caltech/IPAC)

Astronomers have just found one of the youngest planets ever. At only 3 million years old, planet TIDYE-1b (also known as IRAS 04125+2902 b) is practically in its infancy. By comparison, Earth is 4.5 billion years old: that’s 1500 times older. The discovery of a planet this young can teach scientists a lot about the early stages of planet formation, and the peculiarities of this particular one have scientists re-evaluating their models of planetary birth.

November 23, 2024November 23, 2024 by Brian Koberlein

There was Hot Water on Mars 4.45 Billion Years Ago

This artist’s impression shows how Mars may have looked about four billion years ago. The young planet Mars would have had enough water to cover its entire surface in a liquid layer about 140 metres deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars’s northern hemisphere, and in some regions reaching depths greater than 1.6 kilometres. Credit: ESO/M. Kornmesser

Earth and Mars were very similar in their youth. Four billion years ago, both planets had vast, warm seas. But while Earth retained its oceans, the waters of Mars evaporated away or froze beneath its dusty surface. Exactly why these two worlds took such divergent paths is unclear, though it may lie in the origins of their water.

November 23, 2024November 14, 2024 by Paul M. Sutter

Axion Dark Matter May Make Spacetime Ring

An image from the Event Horizon Telescope shows lines of polarization, a signature of magnetic fields, around the shadow of the Milky Way's central supermassive black hole. Astronomers want to know how massive black holes like this one formed early in cosmic history. (Credit: EHT Collaboration)

Dark matter made out of axions may have the power to make space-time ring like a bell, but only if it is able to steal energy from black holes, according to new research.

November 22, 2024November 22, 2024 by Evan Gough

Earth’s Old Trees Keep A Record of Powerful Solar Storms

A solar flare erupts on the Sun. Credit: NASA/GSFC/SDO

Most of the time the Sun is pretty well-mannered, but occasionally it’s downright unruly. It sometimes throws extremely energetic tantrums. During these events, a solar flare or a shock wave from a coronal mass ejection (CME) accelerates protons to extremely high velocities. These are called Solar Particle Events or Solar Proton Events (SPEs).

However, the exact timing of these events can be difficult to ascertain. New research has determined the date of one of the most powerful SPEs to strike Earth during the Holocene.