Universe Today

March 13, 2024March 13, 2024 by Mark Thompson

Are Andromeda and the Milky Way Already Exchanging Stars?

Artist's illustration of Andromeda/Milky Way Merger. Credit: NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger

I often drag out the amazing fact that the Andromeda Galaxy, that faint fuzzy blob just off the corner of the Square of Pegasus, is heading straight for us! Of course I continue to tell people it won’t happen for a few billion years yet but a recent study suggests that we are already seeing hypervelocity stars that have been ejected from Andromeda already. It is just possible that the two galaxies have already started to exchange stars long before they are expected to merge.

March 13, 2024March 13, 2024 by Allen Versfeld

Colliding Neutron Stars are the Ultimate Particle Accelerators

This artist’s impression shows two tiny but very dense neutron stars at the point at which they merge and explode as a kilonova. Such a very rare event is expected to produce both gravitational waves and a short gamma-ray burst, both of which were observed on 17 August 2017 by LIGO–Virgo and Fermi/INTEGRAL respectively. Subsequent detailed observations with many ESO telescopes confirmed that this object, seen in the galaxy NGC 4993 about 130 million light-years from the Earth, is indeed a kilonova. Such objects are the main source of very heavy chemical elements, such as gold and platinum, in the Universe.

Gamma-ray telescopes observing neutron star collisions might be the key to identifying the composition of dark matter. One leading theory explaining dark matter it that is mostly made from hypothetical particles called axions. If an axion is created within the intensely energetic environment of two neutron stars merging, it should then decay into gamma-ray photons which we could see using space telescopes like Fermi-LAT.

March 12, 2024March 12, 2024 by Mark Thompson

This is Europa Clipper’s Version of the Golden Record

Europa Clipper Vault Plate Photographed in JPL Photolab Studio Requester: Preston Dyches, Laurance Fauconnet Date: 01-FEB-2024 Photographer: Ryan Lannom

The Voyager spacecraft carried on board a plethora of scientific instruments but attached to the side was a golden record. The sounds of Earth were recorded upon it. Now, another mission is going to be carrying a message out into space. The Europa Clipper mission will launch in October and it will carry a plaque with images, illustrations and messages. There will be more than 2.6 million names and the word for ‘water’ converted into waveform from 103 languages.

March 12, 2024March 14, 2024 by Mark Thompson

Black Holes are Tearing Stars Apart All Around Us

Illustration of star remnants after it is shredded by a supermassive black hole. Credit: NASA

Galaxy NGC3799 lies around 16 million light years from Earth. Any event observed today within that galaxy took place 16 million years ago. One such event was observed in February 2023 when a surge in brightness in the core was followed by a rapid dimming. The observations that followed revealed that the event was a star being torn apart by a supermassive black hole at the heart of the galaxy. This is not the first time such an event has been observed but it is the first to be within our galactic backyard suggesting it may be more common that first thought.

March 12, 2024March 12, 2024 by Evan Gough

Astronomers Propose a 50-Meter Submillimeter Telescope

The Atacama Large Millimeter/submillimeter Array (ALMA) in northern Chile is our most powerful radio telescope. But astronomers are hungering for a new radio telescope made of one massive dish. Image Credit: A. Marinkovic/X-Cam/ALMA (ESO/NAOJ/NRAO)

Some parts of the Universe only reveal important details when observed in radio waves. That explains why we have ALMA, the Atacama Large Millimetre-submillimetre Array, a collection of 7-meter and 12-meter radio telescopes that work together as an interferometer. But, ALMA-type arrays have their limitations, and astronomers know what they need to overcome those limitations.

They need a radio telescope that’s just one single, massive dish.

March 11, 2024March 11, 2024 by Brian Koberlein

Black Holes Need Refreshing Cold Gas to Keep Growing

A pair of disc galaxies in the late stages of a merger. Credit: NASA

The Universe is filled with supermassive black holes. Almost every galaxy in the cosmos has one, and they are the most well-studied black holes by astronomers. But one thing we still don’t understand is just how they grew so massive so quickly. To answer that, astronomers have to identify lots of black holes in the early Universe, and since they are typically found in merging galaxies, that means astronomers have to identify early galaxies accurately. By hand. But thanks to the power of machine learning, that’s changing.

March 10, 2024March 10, 2024 by Carolyn Collins Petersen

Cyborg Jellyfish Could Help Explore Oceans Autonomously

A scene from a video about cyborg jellyfish created at Caltech. Courtesy Jahn Dabiri

Earth’s oceans are—like space—a largely unexplored frontier. Relatively few humans have explored either place, using specialized life-support equipment. Unlike space, however, the oceans also have other beings that can explore them: jellyfish. They can head to places underwater that humans can never go. That makes them interesting candidates for autonomous ocean exploration.

March 10, 2024March 10, 2024 by Matt Williams

SpaceX is Gearing Up for the Starship’s Third Orbital Test Flight

The fully-stacked Starship and Super Heavy liftoff from the Starbase Launch Facility. Credit: SpaceX

The Starship/Super Heavy is the world’s first fully reusable launch system and the most powerful rocket in history. It is also the key to fulfilling SpaceX’s long-term vision of broadband satellite internet, delivering crews and cargo to the lunar surface, and creating the first self-sustaining city on Mars. After years of development, design changes, and “hop tests” at the company’s launch facility near Boca Chica, Texas, orbital test flights finally began in April last year. The first two flights ended in the loss of both vehicles, though the second flight saw the Starship prototype reach orbit.

According to a recent statement from the company, Flight Test-3 (FT-3) could be happening as soon as Thursday, March 14th, pending approval of the Federal Aviation Administration (FAA). The event will be covered in a live webcast streaming on the company website and SpaceX’s official X (Twitter) account.

March 10, 2024March 10, 2024 by Scott Alan Johnston

Ariane 6 is Coming Together

Part of the first Ariane 6 rocket inside the Vehicle Assembly Building, Kourou, French Guiana earlier in 2024. Credit: ESA/CNES/Arianespace/Arianegroup.

The European Space Agency (ESA)’s next generation heavy lift rocket is just months away from its first flight, and its major components are now being assembled for launch at the Vehicle Assembly Building in Kourou, French Guiana.

March 9, 2024March 17, 2024 by Matt Williams

This Hot Jupiter is Doomed to Crash Into its Star in Just Three Million Years

Artist's impression of the searing-hot gas planet WASP-12b and its star. A Princeton-led team of astrophysicists has shown that this exoplanet is spiraling in toward its host star, heading toward certain destruction in about 3 million years. Credit: NASA/JPL-Caltech

In 2008, astronomers with the SuperWASP survey spotted WASP-12b as it transited in front of its star. At the time, it was part of a new class of exoplanets (“Hot Jupiters”) discovered a little more than a decade before. However, subsequent observations revealed that WASP-12b was the first Hot Jupiter observed that orbits so closely to its parent star that it has become deformed. While several plausible scenarios have been suggested to explain these observations, a widely accepted theory is that the planet is being pulled apart as it slowly falls into its star.

Based on the observed rate of “tidal decay,” astronomers estimate that WASP-12b will fall into its parent star in about ten million years. In a recent study, astronomers with The Asiago Search for Transit Timing Variations of Exoplanets (TASTE) project presented an analysis that combines new spectral data from the Telescopio Nazionale Galileo (TNG) in La Palma with 12 years worth of unpublished transit light curves and archival data. Their results are consistent with previous observations that suggest WASP-12b is rapidly undergoing tidal dissipation and will be consumed by its star.