Universe Today

May 1, 2023May 1, 2023 by Brian Koberlein

Aliens Could Map Earth From its Mobile Phone Towers

A mobile cell tower on a clear day. Credit: Ervins Strauhmanis, via Flickr

Mobile phones are so ubiquitous that we typically don’t think about how they work. They just do, much to our benefit, and sometimes annoyance. But the key to their function is a vast array of radio transmission towers. These cell towers span a large percentage of Earth’s land surface, particularly in heavily populated areas, and they transmit microwave signals all the time. With all those cell towers emitting all those radio signals, a fun question to ask is whether those signals could be detected by an alien civilization.

April 30, 2023April 30, 2023 by Carolyn Collins Petersen

Be Grateful the Sun Can’t Produce Flares Like This

Artist’s impression of the a massive flare -- called a superflare -- observed on one of the stars in the V1355 Orionis binary star system. The binary companion star is visible in the background on the right. (Credit: NAOJ)

Okay, so we all know that the Sun is heading into solar maximum. That means it’s quite a bit more active, with sunspots, coronal mass ejections, and flares aplenty. But, luckily for us, the Sun isn’t as active as the members of the binary star system V1355 Orionis. One of its stars periodically releases superflares. These are ten times more extensive than the largest solar flare ever recorded on the Sun.

April 30, 2023April 30, 2023 by Brian Koberlein

Bizarre Exoplanet Breaks All the Orbital Rules

Artist's view of WASP-39b, a hot gas planet similar to WASP-131b. Credit: NASA, ESA, CSA, Joseph Olmsted (STScI)

In our solar system, the planetary orbits all have a similar orientation. Their orbital planes vary by a few degrees, but roughly the planets all orbit in the same direction. This invariable plane as it’s known also has an orientation within a few degrees of the Sun’s rotational plane. Most planetary systems have a similar arrangement, where planetary orbits and stellar rotation are roughly aligned, but a few exoplanets defy this trend, and we aren’t entirely sure why.

April 30, 2023April 30, 2023 by Carolyn Collins Petersen

A Black Hole Tore a Star to Pieces. The Closest We’ve Ever Seen.

This artist's illustration depicts what astronomers call a "tidal disruption event," or TDE, when an object such as a star wanders too close to a black hole and is destroyed by tidal forces generated from the black hole's intense gravitational forces. (Credit: NASA/CXC/M.Weiss.

We all know that black holes are destructive monsters. Their tremendous gravitational pull sucks in anything that gets in the way. This is particularly true for supermassive black holes in the hearts of galaxies. They can tear apart stars. And, every so often—like once every, 10,000 years, that happens. The star passes too close and the black hole’s gravity shreds it.

April 29, 2023April 29, 2023 by Carolyn Collins Petersen

European Satellite Measures Exactly How Much Ice Has Been Lost from Glaciers

ESA’s Earth Explorer CryoSat mission is dedicated to precise monitoring of changes in the thickness of marine ice floating in the polar oceans and variations in the thickness of the vast ice sheets that blanket Greenland and Antarctica. Its data are being used to measure ice loss in glaciers. Courtesy ESA/AOES Medialab

As global warming heats up our atmosphere a degree at a time, the world’s glaciers are paying the price. In ten years, they’ve shrunk by a total of 2 percent. To look at it another way, collectively the glaciers have lost 2,720 gigatons of ice thanks to warming air.

April 29, 2023April 29, 2023 by Matt Williams

SpaceX Starship Effectively Grounded by FAA After in-Flight Explosion

SpaceX's Starship and Super Heavy booster stand tall on the Starbase launch pad in Texas. Source: SpaceX via YouTube

It was an exciting time when, two weeks ago, SpaceX got the clearance it needed to conduct its first orbital flight test with the Starship and Super Heavy launch system. After years of waiting, SN flight tests, static fire tests, and stacking and unstacking, the long-awaited test of the SN24 Starship and BN7 Booster prototype was on! For this flight, SpaceX hoped to achieve an altitude of at least 150 km (90 mi) above sea level, crossing the 100 km (62 mi) threshold that officially marks the boundary of “space” (aka. the Karman Line) and making a partial transit around the world before splashing down off the coast of Hawaii.

Unfortunately, things began to go awry a few minutes into the flight as the Starship prototype failed to separate from the booster, sending the rocket into a spin that ended in an explosion. While Musk and SpaceX issued statements that the test was largely successful and lots of valuable data was obtained, residents and environmental researchers claim the explosion caused damage to houses in the area and the local environment. In response, the FAA has launched a “mishap investigation,” temporarily grounding the Starship until the explosion’s impact can be assessed.

April 29, 2023April 29, 2023 by Brian Koberlein

These Stars are Already Merging, but Their Future Will Be Catastrophic

Artist's view of the contact binary that will eventually merge as black holes. Credit: UCL / J. daSilva

Close-orbiting binaries are a ticking time bomb. Over time they spiral ever closer to each other until they merge in a cataclysmic explosion such as a supernova. But in the middle of their story, things can get interesting. Some stars collapse into a white dwarf before merging with their partner, others edge so close to each other that their surfaces touch for a time, becoming contact binaries before finally colliding. But one newly discovered binary system will have a wild ride before its final demise.

April 28, 2023April 28, 2023 by Carolyn Collins Petersen

Ingenuity Snaps Another Shot of Perseverance on the Move

This image of NASA's Perseverance Mars rover at the rim of Belva Crater was taken by the agency's Ingenuity Mars Helicopter during the rotorcraft's 51st flight on April 22, 2023, the 772nd Martian day, or sol, of the rover's mission. At the time the image was taken, the helicopter was at an altitude of about 40 feet (12 meters). Check out the chopper's shadow in the lower right, and Perseverance off in the distance at upper left. Courtesy NASA/JPL-Caltech.

Our favorite Martian helicopter did it again. The tiny Ingenuity chopper recently did its 51st flight on Mars. It traveled 188 meters this time (about 617 feet) on April 22, 2023, and reached a maximum altitude of 12 meters (about 39 feet) over the Martian surface. During that time, it snapped another image of its Perseverance mothership, waiting patiently on the horizon.

April 28, 2023April 28, 2023 by Carolyn Collins Petersen

What Would be in a Moon Salad?

SINTEF researcher Galina Simonsen pictured here demonstrating the growing medium for Moon salad in the laboratory at the CIRiS/NTNU Social Research Centre in Trondheim. Photo: Jana Pavlova

Imagine you’re a lunar astronaut, putting in a hard day’s work building your lab or excavating moon rocks. You get back into the hab and ask, “What’s for dinner?” The answer could be “We’re starting with a Moon salad” featuring lettuce and other goodies grown on the lunar surface. It’s an idea scientists are researching as part of a project called LunarPlant, an effort to figure out ways to grow healthy veggies on the Moon.

April 28, 2023April 28, 2023 by Nancy Atkinson

JWST’s MIRI Instrument is Having Problems Again

JWST's Mid-Infrared Instrument (MIRI is shown here, wrapped in its aluminized thermal shield while being integrated into the JWST Integrated Science Instrument Module (ISIM). Credit: NASA/Goddard Space Flight Center/Chris Gunn

Last week, NASA shared a blog post saying they detected a sensor glitch associated with the James Webb Space Telescope’s Mid-Infrared Instrument (MIRI). For some reason, the sensor for MIRI’s Medium Resolution Spectroscopy (MRS) is receiving less light than expected at the longest wavelengths.

NASA is investigating the cause, and said that the instrument is not at risk and no effect has been seen for images taken by MIRI. According to agency officials, all other modes of JWST and MIRI remain unaffected, and they are searching for the underlying issue.