Universe Today

November 18, 2024November 18, 2024 by Brian Koberlein

The Large Magellanic Cloud Survived its Closest Approach to the Milky Way

Illustration of the Large Magellanic Cloud passing through the halo of the Milky Way. Credit: NASA, ESA, Ralf Crawford (STScI)

The Large Magellanic Cloud is a small galaxy, just a tenth of the Milky Way’s mass. It is about 160,000 light years away, which is remarkably close in cosmic terms. In the southern hemisphere it spans the width of 20 Moons in the night sky. While the galaxy seems timeless and unchanging to our short human lives, it is, in fact, a dynamic system undergoing a near collision with our galaxy. Now astronomers are beginning to observe that process.

November 18, 2024November 18, 2024 by Nancy Atkinson

The New Mars Landing Approach: How We’ll Land Large Payloads on the Red Planet

Back in 2007, I talked with Rob Manning, engineer extraordinaire at the Jet Propulsion Laboratory, and he told me something shocking. Even though he had successfully led the entry, descent, and landing (EDL) teams for three Mars rover missions, he said the prospect of landing a human mission on the Red Planet might be impossible.

But now, after nearly 20 years of work and research — as well as more successful Mars rover landings — Manning says the outlook has vastly improved.

“We’ve made huge progress since 2007,” Manning told me when we chatted a few weeks ago in 2024. “It’s interesting how its evolved, but the fundamental challenges we had in 2007 haven’t gone away, they’ve just morphed.”

November 18, 2024November 18, 2024 by Nancy Atkinson

Three More “Galactic Monster” Ultra-Massive Galaxies Found

These three "red monster" galaxies are extremely massive and dusty galaxies in the first billion years after the Big Bang. © NASA/CSA/ESA, M. Xiao & P. A. Oesch (University of Geneva), G. Brammer (Niels Bohr Institute), Dawn JWST Archive.

One of the surprise findings with the James Webb Space Telescope is the discovery of massive galaxies in the early Universe. The expectations were that only young, small, baby galaxies would exist within the first billion years after the Big Bang. But some of the newly found galaxies appear to be as large and as mature as galaxies that we see today.

Three more of these “monster” galaxies have now been found, and they have a similar mass to our own Milky Way. These galaxies are forming stars nearly twice as efficiently as galaxies that were formed later on in the Universe. Although they’re still within standard theories of cosmology, researchers say they demonstrate how much needs to be learned about the early Universe.

November 17, 2024November 17, 2024 by Mark Thompson

James Webb Confirms Hubble’s Calculation of Hubble’s Constant

Artist impression of the James Webb Space Telescope

We have been spoiled over recent years with first the Hubble Space Telescope (HST) and then the James Webb Space Telescope (JWST.) Both have opened our eyes on the Universe and made amazing discoveries. One subject that has received attention from both is the derivation of the Hubble Constant – a constant relating the velocity of remote galaxies and their distances. A recent paper announces that JWST has just validated the results of previous studies by the Hubble Space Telescope to accurately measure its value.

November 17, 2024November 17, 2024 by Mark Thompson

What Should Light Sails Be Made Out Of?

The Breakthrough Starshot program aims to cross the immense distances to the nearest star in just decades. Using a high-powered laser to propel a reflective sail technology to relativistic speeds is their mission. The selection of sail material is key to its success as it must be lightweight while being able to withstand acceleration and radiation from the laser. A recent study explores various materials and proposes that core-shell structures—spherical particles composed of two different materials—could be a promising solution.

November 17, 2024November 17, 2024 by Mark Thompson

A Giant Meteorite Impact 3.26 Billion Years Ago Helped Push Life Forward

Rock and thin section images of the Bruce’s Hill and Umbaumba sections.

The Earth has always been bombarded with rocks from space. It’s true to say though that there were more rocks flying around the Solar System during earlier periods of its history. A team of researchers have been studying a meteorite impact from 3.26 billion years ago. They have calculated this rock was 200 times bigger than the one that wiped out the dinosaurs. The event would have triggered tsunamis mixing up the oceans and flushing debris from the land. The newly available organic material allowed organisms to thrive.

November 16, 2024November 16, 2024 by Alan Boyle

America’s Particle Physics Plan Spans the Globe — and the Cosmos

Illustration showing subatomic particles and galaxies in collision — Particle physics experiments address mysteries at subatomic and astronomical levels. (Illustration by Olena Shmahalo for U.S. Particle Physics)

RALEIGH, N.C. — Particle physicist Hitoshi Murayama admits that he used to worry about being known as the “most hated man” in his field of science. But the good news is that now he can joke about it.

Last year, the Berkeley professor chaired the Particle Physics Project Prioritization Panel, or P5, which drew up a list of multimillion-dollar physics experiments that should move ahead over the next 10 years. The list focused on phenomena ranging from subatomic smash-ups to cosmic inflation. At the same time, the panel also had to decide which projects would have to be left behind for budgetary reasons, which could have turned Murayama into the Dr. No of physics.

Although Murayama has some regrets about the projects that were put off, he’s satisfied with how the process turned out. Now he’s just hoping that the federal government will follow through on the P5’s top priorities.

November 16, 2024November 16, 2024 by Mark Thompson

Millions of Phones Could Map the Earth’s Ionosphere

Ionospheric VTEC from phones during a geomagnetic storm

We are all familiar with the atmosphere of the Earth and part of this, the ionosphere, is a layer of weakly ionized plasma. It extends from 50 to 1,500 km above the planet. It’s a diffuse layer but sufficient to interfere with satellite communications and navigation systems too. A team of researchers have come up with an intriguing idea to utilise millions of mobile phones to help map the ionosphere by relying on their GPS antennas.

November 16, 2024November 16, 2024 by Brian Koberlein

Detecting Primordial Black Hole Mergers Might be Within Our Grasp

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

Imagine a black hole with the mass of the asteroid Ceres. It would be no larger than a bacterium and practically undetectable. But if such black holes are common in the Universe, they would affect the motions of stars and galaxies, just as we observe. Perhaps they are the source of dark matter.

November 16, 2024November 14, 2024 by Paul M. Sutter

What’s Behind the Martian Methane Mystery?

Stitched together from 28 images, this view from NASA's Curiosity Mars rover was captured after the rover ascended the steep slope of a geologic feature called "Greenheugh Pediment." In the distance at the top of the image is the floor of Gale Crater, which is near a region called Aeolis Dorsa that researchers believe was once a massive ocean. The layered structure of the rocks indicated they were created by waterborne sediment. Credit: NASA/JPL-Caltech/MSSS.

The seasonal variations of methane in the Martian atmosphere is an intriguing clue that there might be life hiding under the surface of the red planet. But we won’t know for sure until we go digging for it.