Universe Today

June 28, 2024June 28, 2024 by Carolyn Collins Petersen

Cepheid Variables are the Bedrock of the Cosmic Distance Ladder. Astronomers are Trying to Understand them Better

One of the brightest Cepheid variable stars, RS Puppis. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-Hubble/Europe Collaboration

One of the most fundamental questions astronomers ask about an object is “What’s its distance?” For very faraway objects, they use classical Cepheid variable stars as “distance rulers”. Astronomers call these pulsating stars “standard candles”. Now there’s a whole team of them precisely clocking their speeds along our line of sight.

June 27, 2024June 29, 2024 by Laurence Tognetti

Dark Matter: Why study it? What makes it so fascinating?

Image from NASA’s Hubble Space Telescope of a galaxy cluster that could contain dark matter (blue-shaded region). (Credit: NASA, ESA, M. J. Jee and H. Ford et al. (Johns Hopkins Univ.))

Universe Today has had some incredible discussions with a wide array of scientists regarding impact craters, planetary surfaces, exoplanets, astrobiology, solar physics, comets, planetary atmospheres, planetary geophysics, cosmochemistry, meteorites, radio astronomy, extremophiles, organic chemistry, black holes, cryovolcanism, and planetary protection, and how these intriguing fields contribute to our understanding regarding our place in the cosmos.

Here, Universe Today discusses the mysterious field of dark matter with Dr. Shawn Westerdale, who is an assistant professor in the Department of Physics & Astronomy and head of the Dark Matter and Neutrino Lab at the University of California, Riverside, regarding the importance of studying dark matter, the benefits and challenges, the most exciting aspects about dark matter he’s studied throughout his career, and advice for upcoming students who wish to pursue studying dark matter. So, what is the importance of studying dark matter?

June 27, 2024June 27, 2024 by Mark Thompson

That’s No Planet. Detecting Transiting Megastructures

One of the easiest ways to find exoplanets is using the transit method. It relies upon monitoring the brightness of a star which will then dim as a planet passes in front of it. It is of course possible that other objects could pass between us and a star; perhaps binary planets, tidally distorted planets, exocomets and, ready for it…. alien megastructures! A transit simulator has been created by a team of researchers and it can predict the brightness change from different transiting objects, even Dyson Swarms in construction.

June 27, 2024June 27, 2024 by Andy Tomaswick

A Single Robot Could Provide a Mission To Mars With Enough Water and Oxygen

Utilizing regolith on the Moon or Mars, especially to refill propellant for rockets to get back off the surface, is a common theme in the more engineering-minded space exploration community. There have been plenty of proof-of-concept technologies that could move us toward that goal. One of the best supported was the Regolith Advanced Surface Systems Operations Robot (RASSOR). Let’s take a look at what made this project unique.

June 27, 2024June 27, 2024 by Evan Gough

Webb Sees Globular Clusters Forming in the Early Universe

The Cosmic Gems arc as observed by the JWST. The clusters have the attributes of gravitationally-bound proto-Globular Clusters. Credit: ESA/Webb, NASA & CSA, L. Bradley (STScI), A. Adamo (Stockholm University) and the Cosmic Spring collaboration.

Picture the Universe’s ancient beginnings. In the vast darkness, light was emitted from a particular galaxy only 460 million years after the Big Bang. On the way, the light was shifted into the infrared and magnified by a massive gravitational lens before finally reaching the James Webb Space Telescope.

The galaxy is called the Cosmic Gems arc, and it held some surprises for astronomers.

June 26, 2024June 26, 2024 by Mark Thompson

Fly Through the Pillars of Creation in this New Visualisation Made from Webb and Hubble Data

Webb and Hubble images of the Pillars of Creation

I remember April 1995 very well. It was the month that the stunning and iconic image that has been called ‘Pillars of Creation’ was released. It was taken by the Hubble Space Telescope but now the James Webb Telescope is getting in on the act. Webb snapped images of the Eagle Nebula (home to the ‘pillars’) early on but now astronomers have combined the data form Hubble and Webb to create an amazing 3D animation flight through the nebula.

June 26, 2024June 26, 2024 by Carolyn Collins Petersen

Black Hole Bullies Shut Down Star Formation in Their Galaxies

An artist’s impression of a quasar wind (in light blue) being launched off of the accretion disk (red-orange) around a supermassive black hole. Inset at right are two spectra from the quasar SBS 1408+544, showing the leftward shift of absorbed light that revealed the acceleration of gas pushed by quasar winds. Image: NASA/CXC/M. Weiss, Catherine Grier and the SDSS collaboration

A supermassive black hole in the heart of a galaxy is the ultimate 800-pound gorilla of astrophysics. Not only do the most active ones suck in material and hide it away, but their accretion disks also blast strong quasar winds out to space. Those winds push things around, and in the process, they sometimes shut down star formation.

June 26, 2024June 26, 2024 by Andy Tomaswick

Can We Use An Asteroid’s Own Dust to Deflect It?

Deflecting potentially hazardous asteroids (PHAs) is one of humanity’s most critical long-term efforts to ensure we don’t suffer the fate of the dinosaurs. There are plenty of suggested mission architectures to move a PHA out of the way, the most famous of which was the Double Asteroid Redirection Test (DART), which successfully changed the orbit of Dimorphos, a harmless small asteroid. That proof of concept bodes well for our chances of deflecting any future PHAs as long as they are discovered in time. But when it comes to the safety of the planet, we can’t be too careful, so developing more ways to deflect a PHA is better, and a paper from researchers at Beihang University details a methodology that is gaining some traction lately – using an asteroid’s regolith as a propellant.

June 25, 2024June 25, 2024 by Alan Boyle

How Commercial Satellites Could Track Spy Balloons and Other UFOs

Chinese spy balloon tracked on satellite imagery — Crosses indicate the apparent position of a spy balloon over Missouri as seen in different spectral bands. (Credit: Planet Labs / Keto and Watters)

It turns out that you don’t need the Men in Black to spot unidentified anomalous phenomena, which are also known as UAPs, unidentified flying objects or UFOs. Researchers have shown how the task of detecting aerial objects in motion could be done by analyzing Earth imagery from commercial satellites.

They say they demonstrated the technique using one of the most notorious UAP incidents of recent times: last year’s flight of a Chinese spy balloon over the U.S., which ended in a shootdown by an Air Force fighter jet above the Atlantic Ocean. They also analyzed imagery of a different spy balloon that passed over Colombia at about the same time.

“Our proposed method appears to be successful and allows the measurement of the apparent velocity of moving objects,” the researchers report.

June 25, 2024June 25, 2024 by Mark Thompson

Saturn’s Energy is Out of Balance

Energy imbalance of Saturn (image credit: NASA/JPL)

Earth releases about as much energy out into space as it absorbs, arriving at a thermal equilibrium. This means it will reach an average temperature as is the case with most planets. Saturn however, is a little different as recent observations show the planet’s energy is out of balance. It seems that in addition to the energy it receives from the Sun, there must also be an internal source of heat, perhaps driven by its highly elliptical orbit.