Universe Today

December 26, 2023December 18, 2023 by Paul M. Sutter

We Owe Our Lives to the Moon

Occultation — The occultation of Aldebaran by the Moon in 2016. Credit: Andrew Symes.

Life appeared on Earth through a series of lucky coincidences, and that luck started with our Moon. None of the other planets of the inner solar system have significant moons. Space is lonely around Mercury and Venus. Mars does have two small moons, Phobos and Deimos (Fear and Despair, befitting companions for the God of War), but those are simply captured asteroids, lassoed in the not-too-distant past and doomed to eventually come close enough to their unloving parent to be torn to shreds by gravitational forces.

December 26, 2023February 26, 2024 by David Dickinson

Top Astronomy Events for 2024

Astronomy 2024 features the final total solar eclipse for the CONUS until 2044, and much more.

It’s finally time. On April 8^th, 2024, the umbral shadow of the Moon crosses the United States for the second time in less than seven years. It’s a big deal, for sure. But there’s lots more in store for astronomy 2024. Here’s our annual Universe Today rundown for top skywatching events to watch for in astronomy 2024, coming to a sky near you.

December 23, 2023December 23, 2023 by Andy Tomaswick

Miniaturized Jumping Robots Could Study An Asteroid’s Gravity

Missions focusing on small bodies in the solar system have been coming thick and fast lately. OSIRIS-Rex, Psyche, and Rosetta are all examples of projects that planned or did rendezvous with a small body in the solar system. But one of their biggest challenges is understanding the gravity of these bodies – which was especially evident when Philae, Rosetta’s lander, had a hard time staying on the surface of its intended comet. A new idea from researchers at the University of Colorado Boulder and NASA’s Jet Propulsion Laboratory could help solve that problem – by bouncing small probes around.

December 23, 2023December 18, 2023 by Paul M. Sutter

How Supersymmetry Saved String Theory

According to supersymmetry, dark-matter particles known as neutralinos (which are often called WIMPs) annihilate each other, creating a cascade of particles and radiation that includes medium-energy gamma rays. If neutralinos exist, the LAT might see the gamma rays associated with their demise. Credit: Sky & Telescope / Gregg Dinderman.

String theory, like most revolutions, had humble origins. It started all the way back in the 1960’s as an attempt to understand the workings of the strong nuclear force, which had only recently been discovered. Quantum field theory, which had been used successfully to explain electromagnetism and the weak nuclear force, wasn’t seeming to cut it, and so physicists were eager for something new.

December 23, 2023December 23, 2023 by Andy Tomaswick

Using Smart Materials To Deploy A Dark Age Explorer

One of the most significant constraints on the size of objects placed into orbit is the size of the fairing used to put them there. Large telescopes must be stuffed into a relatively small fairing housing and deployed to their full size, sometimes using complicated processes. But even with those processes, there is still an upper limit to how giant a telescope can be. That might be changing soon, with the advent of smart materials – particularly on a project funded by NASA’s Institute for Advanced Concepts (NIAC) that would allow for a kilometer-scale radio telescope in space.

December 23, 2023December 23, 2023 by Brian Koberlein

The Atmosphere of an Exoplanet Reveals Secrets About Its Surface

An artist’s concept of active volcanoes on Venus. Credit: NASA/JPL-Caltech/Peter Rubin

As astronomers have begun to gather data on the atmospheres of planets, we’re learning about their compositions and evolution. Thick atmospheres are the easiest to study, but these same thick atmospheres can hide the surface of a planet from view. A Venus-like world, for example, has such a thick atmosphere making it impossible to see the planet’s terrain. It seems the more likely we are to understand a planet’s atmosphere, the less likely we are to understand its surface. But that could change thanks to a new study in the Monthly Notices of the Royal Astrophysical Society.

December 22, 2023December 22, 2023 by Matt Williams

NASA Tightbeams a Cat Video From 31 Million Kilometers Away

This 15-second clip shows the first ultra-high-definition video sent via laser from deep space, featuring a cat named Taters chasing a laser with test graphics overlayed. Credit: NASA/JPL-Caltech

NASA’s Deep Space Network (DSN) has been responsible for maintaining contact with missions venturing beyond Low Earth Orbit (LEO) since 1963. In addition to relaying communications and instructions, the DSN has sent breathtaking images and invaluable science data back to Earth. As missions become more sophisticated, the amount of data they can gather and transmit is rapidly rising. To meet these growing needs, NASA has transitioned to higher-bandwidth radio spectrum transmissions. However, there is no way to increase data rates without scaling the size of its antennas or the power of its radio transmitters.

To meet these needs, NASA has created the Deep Space Optical Communications (DSOC), which relies on focused light (lasers) to stream very high-bandwidth video and other data from deep space. Compared to conventional radio, optical arrays are typically faster, more secure, lighter, and more flexible. In a recent test, NASA used this technology demonstrator to beam a video to Earth from a record-setting distance of 31 million km (19 million mi) – about 80 times the distance between the Earth and the Moon. The video, featuring a cat named Taters, marks a historic milestone and demonstrates the effectiveness of optical communications.

December 22, 2023December 22, 2023 by Matt Williams

Watch 14 Years of Gamma-Ray Observations in This Fascinating NASA Video

Still from the video showing 14 years of data gathered by the Fermi Gamma-ray Space Telescope. Credit: NASA Goddard

The Fermi Gamma-ray Space Telescope, named in honor of noted physicist Enrico Fermi, has been in operation for almost a decade and a half, monitoring the cosmos for gamma rays. As the highest-energy form of light, these rays are produced by extremely energetic phenomena – like supernovae, neutron stars, quasars, and gamma-ray bursts (GRBs). In honor of this observatory’s long history, NASA’s Goddard Spaceflight Center has released a time-lapse movie that shows data acquired by the Fermi Space Telescope between August 2008 and August 2022.

December 22, 2023December 22, 2023 by Nancy Atkinson

Questions Remain on Chinese Rocket That Created an Unusual Double Crater on the Moon

A rocket body impacted the Moon on March 4, 2022, near Hertzsprung crater, creating a double crater roughly 28 meters wide in the longest dimension. Credits: NASA/Goddard/Arizona State University

In November, we reported how an impact on the Moon from a Chinese Long March rocket booster created an unusual double crater. For a single booster to create a double crater, some researchers thought there must have been an additional – perhaps secret – payload on the forward end of the booster, opposite from the rocket engines. But that may not necessarily be the case.

Other researchers feel the extra mass wasn’t anything secretive, but possibly an inert structure such as a payload adapter added to the rocket to support the primary mission payload.

December 22, 2023December 22, 2023 by Paul M. Sutter

Holograms Might Save Physics

Observations made with ESO’s Very Large Telescope (VLT) have revealed for the first time that a star orbiting the supermassive black hole at the centre of the Milky Way moves just as predicted by Einstein’s theory of general relativity. Its orbit is shaped like a rosette and not like an ellipse as predicted by Newton's theory of gravity. This effect, known as Schwarzschild precession, had never before been measured for a star around a supermassive black hole. This artist’s impression illustrates the precession of the star’s orbit, with the effect exaggerated for easier visualisation.

Even though the guts of General Relativity are obtusely mathematical, and for decades was relegated to math departments rather than proper physics, you get to experience the technological gift of relativity every time you navigate to your favorite restaurant. GPS, the global positioning system, consists of a network of orbiting satellites constantly beaming out precise timing data. Your phone compares those signals to figure out where you are on the Earth. But there is a difference in spacetime between the surface of the Earth and the orbit of the satellites. Without taking general relativity into account, your navigation would simply be incorrect, and you’d be late for dinner.