Universe Today

September 25, 2024September 25, 2024 by Brian Koberlein

Biosignatures Can be Made in the Lab. No Life Needed.

The most likely way we will discover life on a distant exoplanet is by discovering a biosignature. This can be done by looking at the atmospheric spectra of a world to discover the spectral pattern of a molecule that can only be created through biological processes. While it sounds straightforward it isn’t. The presence of simple molecules such as water and oxygen don’t prove life exists on a planet. It’s true that Earth’s atmosphere is oxygen rich thanks to life, but geological activity can also produce large quantities of oxygen. And as a new study shows, some molecules we’ve long thought to be biological in origin may not be.

September 24, 2024September 24, 2024 by Evan Gough

How a Nearby Supernova Left its Mark on Earth Life

Artist's impression of a supernova. Supernovae bombarded Earth with radiation that has implications for the development of life on Earth. Image Credit: NASA

When a massive star explodes as a supernova, it does more than release an extraordinary amount of energy. Supernovae explosions are responsible for creating some of the heavy elements, including iron, which is blasted out into space by the explosion. On Earth, there are two accumulations of the iron isotope Fe60 in sea-floor sediments that scientists trace back about two or three million years ago and about five to six million years ago.

The explosions that created the iron also dosed Earth with cosmic radiation.

September 24, 2024September 24, 2024 by Matt Williams

SpaceX Recovers the Super Heavy Booster from Flight 4

The remains of the SpaceX Booster BN11 being retrieved from the Gulf of Mexico. Credit: SpaceX

On June 6th, 2024, the fourth orbital test flight of the Starship successfully lifted off at 07:50 a.m. CT (08:50 a.m. EDT; 06:50 PDT) from SpaceX’s Starbase in Texas. This test was the first time the Starship (SN29) and Super Heavy (BN11) prototypes reentered Earth’s atmosphere and landed successfully. While the SN29 conducted a powered vertical landing before splashing down in the Indian Ocean, the BN11 executed a similar powered landing before splashing down in the Gulf of Mexico. In a recent tweet, Elon Musk shared a photo of the BN11 booster being pulled out of the sea.

September 24, 2024September 24, 2024 by Nancy Atkinson

Shape-Shifting Robots Mimic Muscle Movements

HEXEL modules snap together for a large-stroke muscle and a multi-modal array. Credit: Zachary Yoder / MPI-IS Ellen Rumley / MPI-IS

Researchers have developed a set of hexagon-shaped robotic components that can be snapped together into larger and larger structures. Each one of the component hexagons is made of rigid plates that serve as its exoskeleton. Driven by electricity, the plates can change their shape, shifting from long and narrow to wide and flat at high speed. The combined structures are capable of jumping four times their own body height, then can shape-shift to roll extremely fast, or use multimodal actuation to crawl through confined spaces.

September 23, 2024September 23, 2024 by Mark Thompson

What Happens to the Climate When Earth Passes Through Interstellar Clouds?

Orion Molecular Cloud Complex, dominated in the center of this view by the brilliant Flame nebula (NGC 2024). The smaller, glowing cavity falling between the Flame nebula and the Horsehead is called NGC 2023. Image credit: NASA/JPL-Caltech.

Noctilucent clouds were once thought to be a fairly modern phenomenon. A team of researcher have recently calculated that Earth and the entire Solar System may well have passed through two dense interstellar clouds causing global noctilucent clouds that may have driven an ice age. The event is thought to have happened 7 million years ago and would have compressed the heliosphere, exposing Earth to the interstellar medium.

September 23, 2024September 23, 2024 by Evan Gough

From Frozen to Sweltering: Earth’s Climate Over the Last 485 Million Years

New research shows the global mean surface temperature across the last 485 million years. The gray shading corresponds to different confidence levels, and the black line shows the average. The colored bands along the top reflect the climate state, with cooler colors indicating icehouse (coolhouse and coldhouse) climates, warmer colors indicating greenhouse (warmhouse and hothouse) climates, and the gray representing a transitional state. Image Credit: Judd et al. 2024.

Earth’s last half-billion years were action-packed. During that time, the climate underwent many changes. There have been changes in ocean levels and ice sheets, changes in the atmosphere’s composition, changes in ocean chemistry, and ongoing biological evolution punctuated with extinction events.

A record of Earth’s temperature over the last 485 million years is helping scientists understand how it all played out and illustrating what could happen if we continue to enrich the atmosphere with carbon.

September 23, 2024September 23, 2024 by Brian Koberlein

Those Aren't Dyson Spheres, They're HotDOGs

Imagining the Universe as a collection of stellar bubbles. Credit: NASA

If there really are advanced alien civilizations out there, you’d think they’d be easy to find. A truly powerful alien race would stride like gods among the cosmos, creating star-sized or galaxy-sized feats of engineering. So rather than analyzing exoplanet spectra or listening for faint radio messages, why not look for the remnants of celestial builds, something too large and unusual to occur naturally?

September 23, 2024September 23, 2024 by Mark Thompson

A New Catalog Charts the Evolution of the Universe Over Time

The William Herschel Telescope in La Palma, Spain. Image credit: PAUS team.

An atlas doesn’t seem to be an essential item in cars these days but think about them and most people will think about distances. An atlas of the stars not only covers distances but must also take into account time too. The Andromeda galaxy for example is so far away that its light takes 2.5 million years to reach us. A team of researchers have now built a catalogue that contains information on millions of galaxies including their distance and looks back in time up to 10 billion years!

September 22, 2024September 22, 2024 by Carolyn Collins Petersen

This Might Be the Best Gravitational Lens Ever Found

The Carousel Lens, as seen through the Hubble Space Telescope. Credit: William Sheu/UCLA

A gravitational lens is the ultimate funhouse mirror of the Universe. It distorts the view of objects behind them but also supplies amazing information about distant galaxies and quasars. Astronomers using Hubble Space Telescope (HST) recently released a new image of one of these weird apparitions called “The Carousel Lens”. It’s a rare alignment of seven background galaxies that all appear distorted by an intervening galaxy cluster.

September 22, 2024September 22, 2024 by Matt Williams

High-Resolution Images of the Sun Show How Flares Impact the Solar Atmosphere

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

Solar flares are a fascinating thing and have a profound effect on what astronomers refer to as “space weather.” These events vary with the Sun’s 11-year solar cycle, releasing immense amounts of radiation across the electromagnetic spectrum (from extreme ultraviolet to X-rays) into space. The effects of flares have been observed since time immemorial, which include aurorae at high latitudes (Aurora Borealis and Australis), but have only been the subject of study and prediction for about a century and a half. Still, there is much that remains unknown about these dramatic events.

For instance, flares are known to affect the Sun’s atmosphere, from the visible surface (photosphere) to its outermost layer (corona). However, there are still questions about how these events influence the lower layers of the atmosphere. In a recent study led by the University of Colorado, Boulder, a team of researchers documented the rotation of two very small sunspots of the Sun’s surface (pores) using the Daniel K. Inouye Solar Telescope (DKIST) at Mauna Kea. These pores were linked to a less powerful flare and moved in a way that has never been observed, suggesting that the dynamics of the Sun’s atmosphere are more complex than previously thought.