Universe Today

December 21, 2022December 21, 2022 by Evan Gough

Webb Stares Deeply Into the Universe, Showing How Galaxies Assemble

This image represents a portion of the full PEARLS field, which will be about four times larger. Thousands of galaxies over an enormous range in distance and time are seen in exquisite detail, many for the first time. Image Credit: SCIENCE: NASA, ESA, CSA, Rolf A. Jansen (ASU), Jake Summers (ASU), Rosalia O'Brien (ASU), Rogier Windhorst (ASU), Aaron Robotham (UWA), Anton M. Koekemoer (STScI), Christopher Willmer (University of Arizona), JWST PEARLS Team IMAGE PROCESSING: Rolf A. Jansen (ASU), Alyssa Pagan (STScI)

The James Webb Space Telescope is delivering a deluge of images and data to eager scientists and other hungry-minded people. So far, the telescope has shown us the iconic Pillars of Creation like we’ve never seen them before, the details of very young stars as they grow inside their dense cloaks of gas, and a Deep Field that’s taken over from the Hubble’s ground-breaking Deep Field and Ultra Deep Field images. And it’s only getting started.

True to its main science objectives, the JWST has peered back in time to the Universe’s earliest galaxies looking for clues to how they assemble and evolve.

December 21, 2022December 23, 2022 by Matt Williams

Astronomers Scanned 12 Planets for Alien Signals While They Were in Front of Their Stars

TOI 1338 b is a circumbinary planet orbiting its two stars. It was discovered by TESS. Image Credit: NASA's Goddard Space Flight Center/Chris Smith

The Robert C. Byrd Green Bank Telescope (GBT), part of the Green Bank Observatory in West Virginia, is the world’s premiere single-dish radio telescope. Between its 100-meter dish (328-foot), unblocked aperture, and excellent surface accuracy, the GBT provides unprecedented sensitivity in the millimeter to meter wavelengths – very high to extremely high frequency (VHF to EHF). Since 2017, it also became one of the main instruments used by Breakthrough Listen and other institutes engaged in the Search for Extraterrestrial Intelligence (SETI).

Recently, an international team of researchers from the SETI Institute, Breakthrough Listen, and multiple universities scanned twelve exoplanets for signs of technological activity (aka. “technosignatures”). Their observations were timed to coincide with the planets passing in front of their sun relative to the observer (i.e., making a transit). While the survey did not detect any definitive evidence of technosignatures, they did identify two radio signals of interest that warrant follow-up observation. This new technique could vastly expand the field of SETI and create all kinds of opportunities for future research.

December 21, 2022December 22, 2022 by Matt Williams

What Kind of an Impact did DART Have on Dimorphos? The Science Results are Here

Tail — Two tails of dust ejected from the Didymos-Dimorphos asteroid system are seen in new images from the NASA/ESA Hubble Space Telescope, Credit: NASA/ESA

On September 26th, NASA’s Double Asteroid Redirection Test (DART) spacecraft collided with Dimorphos, the small moonlet that orbits the larger Near-Earth Asteroid (NEA) Didymos. The purpose was to test a planetary defense technique known as the kinetic impact method, where a spacecraft intentionally collides with a Potentially Hazardous Asteroid (PHAs) to alter its course. Based on a post-collision analysis, NASA determined that DART’s impact altered Dimorphos’ orbital period by 33 minutes and caused tons of rock to be ejected from its surface.

Since the collision, NASA has also been monitoring the cloud of ejecta produced by the impact to see how it has since evolved. The purpose of this is to better understand what the DART spacecraft achieved at the impact site, how much of it was delivered by the spacecraft, and how much was due to the recoil produced by the ejection. On December 15th, during the Fall Meeting of the American Geophysical Union (AGU) in Chicago, members of the DART team provided the preliminary analysis of their findings.

December 21, 2022December 21, 2022 by Evan Gough

Comet Impacts Could Have Brought the Raw Ingredients for Life to Europa’s Ocean

An artist's concept of a comet or asteroid impact on Jupiter's moon Europa. Credit: NASA/JPL-Caltech

Jupiter is the most-visited planet in the Solar System, thanks largely to NASA. It all started with Pioneer 10 and 11, followed by Voyager 1 and 2. Those were all flyby missions, and it wasn’t until 1996 that the Galileo spacecraft became the first to orbit the gas giant and even send a probe into its atmosphere. Then in 2016, the Juno spacecraft entered orbit around Jupiter and is still there today.

All of these missions were focused on Jupiter, but along the way, they gave us tantalizing hints of the icy moon Europa. The most impactful thing we’ve learned is that Europa, though frozen on the surface, holds an ocean under all that ice. And that warm, salty ocean might contain more water than all of Earth’s oceans combined.

Might it hold life?

December 20, 2022December 22, 2022 by Matt Williams

For the First Time, Astronomers Spot Stars in Galaxies that Existed Just 1 Billion Years After the Big Bang

Artist impression of a powerful young quasar. Credit: ESO/M. Kornmesser Credit: ESO/M. Kornmesser

Since it launched on December 25th, 2021 (quite the Christmas present!), the James Webb Space Telescope (JWST) has taken the sharpest and most detailed images of the Universe, surpassing even its predecessor, the venerable Hubble Space Telescope! But what is especially exciting are the kinds of observations we can look forward to, where the JWST will use its advanced capabilities to address some of the most pressing cosmological mysteries. For instance, there’s the problem presented by high-redshift supermassive black holes (SMBHs) or brightly-shining quasars that existed during the first billion years of the Universe.

To date, astronomers have not been able to determine how SMBHs could have formed so soon after the Big Bang. Part of the problem has been that, until recently, stars in host galaxies with redshift values of Z>2 (within 10.324 billion light-years) have been elusive. But thanks to the JWST, an international team of astronomers recently observed stars in quasars at Z>6 (within 12.716 billion light-years) for the first time. Their observations could finally allow astronomers to assess the processes in early quasars that governed the formation and evolution of the first SMBHs.

December 20, 2022December 20, 2022 by Evan Gough

We Could Spread Life to the Milky Way With Comets. But Should We?

Gerald Rhemann captured this incredible image of Comet Leonard when a piece of the comet's tail was disconnected and carried away. Rhemann won Astronomy Photographer of the Year 2022 for the image. Image Credit: Gerald Rhemann

Here’s a thorny problem: What if life doesn’t always appear on planets that can support it? What if we find more and more exoplanets and determine that some of them are habitable? What if we also determine that life hasn’t appeared on them yet?

Could we send life-bringing comets to those planets and seed them with terrestrial life? And if we could do that, should we?

December 19, 2022January 28, 2023 by Matt Williams

Hubble and Spitzer Team up to Find a Pair of Waterworld Exoplanets

Artist’s impression of a water world, where half of its mass consists of water. Just like our Moon, the planet is bound to its star by tidal forces and always shows the same face to its host star. Credit: Pilar Montañés

As of December 19th, 2022, 5,227 extrasolar planets have been confirmed in 3,908 systems, with over 9,000 more awaiting confirmation. While most of these planets are Jupiter- or Neptune-sized gas giants or rocky planets many times the size of Earth (Super-Earths), a statistically significant number have been planets where water makes up a significant part of their mass fraction – aka. “water worlds.” These planets are unlike anything we’ve seen in the Solar System and raise several questions about planet formation in our galaxy.

In a recent study, an international team led by researchers from the University of Montreal’s Institute for Research on Exoplanets (iREx) found evidence of two water worlds in a single planetary system located about 218 light-years away in the constellation Lyra. Based on their densities, the team determined that these exoplanets (Kepler-138c and Kepler-138d) are lighter than rocky “Earth-like” ones but heavier than gas-dominated ones. The discovery was made using data from NASA’s now-retired Spitzer Space Telescope and the venerable Hubble Space Telescope.

December 19, 2022December 19, 2022 by Carolyn Collins Petersen

Giant Exoplanet is Spiraling Inward to its Doom

Kepler 1658b may spiral in to its aging star in the distant future. Credit: Gabriel Perez Diaz/Instituto de Astrofísica de Canarias

“Death by star” is a fate awaiting most planets in star systems. That includes our Sun, Venus, and Mercury a few billion years from now. And, astronomers now see that same fate awaiting Kepler-1658b. It’s a hot Jupiter exoplanet orbiting an evolved F-type yellow-white dwarf star about 2600 light-years away from Earth.

December 19, 2022December 19, 2022 by Evan Gough

JWST Sees Furious Star Formation in a Stellar Nursery

Image of the Carina Nebula (NGC 3324) captured by Webb’s Near-Infrared Camera (NIRCam), Credit: NASA/ESA/CSA/STScI

The powerful James Webb Space Telescope is a mighty technological tool. Astrophysicists first conceived it over 20 years ago, and after many twists and turns, it was launched on December 2st, 2021. Now it’s in a halo orbit at the Sun-Earth L2 point, where it will hopefully continue operating for 20 years.

It’s only been a few months since its first images were released, and it’s already making progress in answering some of the Universe’s most compelling questions. In a newly-released image, the JWST peered deep inside massive clouds of gas and dust to watch young stars come to life in their stellar cocoons.

December 19, 2022December 19, 2022 by Matt Williams

Gravitational Wave Observatories Could Search for Warp Drive Signatures

Artist's impression of a Dyson Sphere. The construction of such a massive engineering structure would create a technosignature that could be detected by humanity. Credit: SentientDevelopments.com/Eburacum45

In 2016, scientists at the Laser Interferometer Gravitational-Wave Observatory (LIGO) announced that they had made the first confirmed detection of gravitational waves (GWs). This discovery confirmed a prediction made a century before by Einstein and his Theory of General Relativity and opened the door to a whole new field of astrophysical research. By studying the waves caused by the merger of massive objects, scientists could probe the interior of neutron stars, detect dark matter, and discover new particles around supermassive black holes (SMBHs).

According to new research led by the Advanced Propulsion Laboratory at Applied Physics (APL-AP), GWs could also be used in the Search for Extraterrestrial Intelligence (SETI). As they state in their paper, LIGO and other observatories (like Virgo and KAGRA) have the potential to look for GWs created by Rapid And/or Massive Accelerating spacecraft (RAMAcraft). By combining the power of these and next-generation observatories, we could create a RAMAcraft Detection And Ranging (RAMADAR) system that could probe all the stars in the Milky Way (100 to 200 billion) for signs of warp-drive-like signatures.