Universe Today

March 13, 2024March 13, 2024 by Mark Thompson

NASA Announces its 2025 Budget. Lean Times Ahead.

Space flight is an expensive business and that money has to come from somewhere. The White House has just released their budget for fiscal year 2025. What does that mean for NASA?, they will get $25.4 billion, the same as it received last year but $2 billion less than it requested. NASA Administrator Bill Nelson said the constraints come from a debt ceiling agreement that limits non-defence spending. Alas the $2 billion deficit means NASA will need to cut costs from various missions.

March 13, 2024March 13, 2024 by Brian Koberlein

A 790,000 Year-Old Asteroid Impact Could Explain Seafloor Spherules

A 0.4-millimeter diameter iron-rich spherule. Credit: Avi Loeb/The Galileo Project

Our solar system does not exist in isolation. It formed within a stellar nursery along with hundreds of sibling stars, and even today has the occasional interaction with interstellar objects such as Oumuamua and Borisov. So it’s reasonable to presume that some interstellar material has reached Earth. Recently Avi Loeb and his team earned quite a bit of attention with a study arguing that it had found some of this interstellar stuff on the ocean seabed. But a new study finds that the material has a much more local origin.

March 13, 2024March 13, 2024 by Mark Thompson

Ultrablack Coating Could Be Ideal for Telescopes

The team’s ultrablack coating can be applied to curved surfaces and magnesium alloys to trap nearly all light.

If you, like me, have dabbled with telescope making you will know what a fickle friend light can be. On one hand you want to capture as much as you can (but only from the object, not from nearby lights) and want to reflect or refract it to the point of observation or study. What you most certainly don’t want is stray light to be bounced around inside the telescope so components (except the mirror!) are sprayed as black as possible. Unfortunately black paints tend to be quite susceptible to damage and struggle to cope with the harsh conditions and cold temperatures telescopes are subjected to. A team has recently developed a new atomic-layer deposition method which absorbs 99.3% of light and is durable too.

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.