Universe Today

January 2, 2024January 3, 2024 by Matt Williams

After all of This Time Searching for Aliens, is it The Zoo Hypothesis or Nothing?

The Karl Jansky Very Large Array at night, with the Milky Way visible in the sky. Credit: NRAO/AUI/NSF; J. Hellerman

In 1950, during a lunchtime conversation with colleagues at the Los Alamos National Laboratory, famed physicist Enrico Fermi asked the question that launched a hundred (or more) proposed resolutions. “Where is Everybody?” In short, given the age of the Universe (13.8 billion years), the fact that the Solar System has only existed for the past 4.5 billion years, and the fact that the ingredients for life are everywhere in abundance, why haven’t we found evidence of extraterrestrial intelligence by now? This came to be the basis of Fermi’s Paradox, which remains unresolved to this day.

Interest in Fermi’s question has been piqued in recent years thanks to the sheer number of “potentially habitable” exoplanets discovered in distant star systems. Despite that, all attempts to find signs of technological activity (“technosignatures”) have come up empty. In a recent study, a team of astrobiologists considered the possible resolutions and concluded that only two possibilities exist. Either extraterrestrial civilizations (ETCs) are incredibly rare (or non-existent), or they are deliberately avoiding contact with us (aka. the “Zoo Hypothesis“).

January 2, 2024January 2, 2024 by Mark Thompson

An Ancient Stone Found in Italy is an Accurate Map of the Night Sky

Digital elevation model of the frontal face of Rupinpiccolo stone disk from an adaptation of fig. 1 of Bernardini et al. (2022). The orientation is arbitrary

You know how some constellations take a little bit of imagination to see? Yes, Leo looks a bit like a lion and Orino a bit like a hunter but then we drift into the realms of powerful levels of imagination to be able to see Pegasus as a flying horse or Telescopium as a telescope! Even squinting or tilting your head really doesn’t make them visible. I found the same problem when looking at images of two stone disks discovered in Italy recently at the entrance to an ancient fort! Teams that have examined the stones have matched the subtle markings on them to positions of 28 bright stars in the sky! I had to really look to see it but I think they might actually be right!

January 2, 2024January 2, 2024 by Mark Thompson

The Sun Just Blasted its Strongest Flare in 6 Years. Get Ready for Auroras

While many of us were celebrating the end of 2023 and the coming of 2024, the Sun was having its own celebration blasting an X5.0 flare from sunspot region 3536. Records show this to be the most powerful flare seen since 10 September 2017 when an X8.2 flare erupted. The flare is expected to arrive around Jan 2 – EEK that’s today! Get your aurora watching kit out!

January 2, 2024January 2, 2024 by Mark Thompson

Simulation Perfectly Matches What We See When Neutron Stars Collide

Numerical simulation of the resulting ejecta material of two merging neutron stars. Red colors refer to ejected material with a high fraction of neutrons which will appear typically redder than blue material that contains a higher fraction of protons. © I. Markin (University of Potsdam)

There are many mysteries in the world of astronomy and a fair number relate to the processes during the end of the life of a super massive star. Throw in the complexity of collisions and you have a real head scratching problem on your hands. In 2017 colliding neutron stars were detected and the data has allowed a new simulation to be tested with predictions beautifully matching observation.

January 2, 2024January 2, 2024 by Evan Gough

You’ll Need all the Internet to Download the Full Resolution of this New Running Chicken Nebula Image

The Running Chicken Nebula comprises several clouds, all of which we can see in this vast image from the VLT Survey Telescope (VST), hosted at ESO’s Paranal site. This 1.5-billion pixel image spans an area in the sky of about 25 full Moons. Image Credit: ESO/VST

Over 6,000 light-years from Earth, an open star cluster and its nebula cover a swathe of sky over 270 light-years across. It’s called the Running Chicken Nebula, and it’s more than just one object. The Running Chicken Nebula, also called IC 2944, also contains IC 2948, the brightest part of the Chicken, as well as several Bok Globules and smaller nebulae. The bright star Lambda Centauri is near the visual center of the Chicken but is actually much closer to Earth.

January 1, 2024January 1, 2024 by Mark Thompson

ESA’s Tiny Pinhole Thruster is Ready for Production.

ATHENA - Adaptable, THurster based on Electrospray powered NAnotechnology

Rocket propulsion technology has progressed leaps and bounds since the first weaponised rockets of the Chinese and Mongolian empires. They were nothing more than rocket powered arrows and spears but they set the foundations for our exploration of space. Liquid propellant, ion engines and solar sails have all hit the headlines as we strive for more efficient methods of travel but a team has taken the next leap with a palm sized thruster system that could boost future tiny space craft across the gulf of space.

December 31, 2023December 31, 2023 by Carolyn Collins Petersen

How a Small Town in Japan Fiercely Defends its Dark Skies

The arch of the Milky Way seen over Bisei Town in Japan. It prides itself on its dark skies, but faces scattered light pollution from other nearby municipalities. Courtesy DarkSky.Org.

Light pollution ruins dark skies. It’s a scourge that ground-based observatories have to deal with in one form or another. Scientists used a small observatory in Japan to measure what changed when a nearby town improved its lighting practices. They also noted the challenges it still faces.

December 31, 2023December 31, 2023 by Laurence Tognetti

How Many Planets Could Be in the Kuiper Belt?

A recent study published in The Astrophysical Journal Letters investigates the potential existence of Mars-sized free-floating planets (FFPs)—also known as rogue planets, starless planets, and wandering planets—that could have been captured by our Sun’s gravity long ago and orbit in the outer solar system approximately 1,400 astronomical units (AU) from the Sun. For context, the farthest known planetary body in the solar system is Pluto, which orbits approximately 39 AU from the Sun, and is also part of the Kuiper Belt, which scientists estimate extends as far out as 1,000 AU from the Sun.

December 31, 2023December 31, 2023 by Laurence Tognetti

TRAPPIST-1c Isn’t the Exo-Venus We Were Hoping For. But Don’t Blame the Star

A recent study accepted to The Astrophysical Journal uses computer models to investigate why the exoplanet, TRAPPIST-1c, could not possess a thick carbon dioxide (CO2) atmosphere despite it receiving the same amount of solar radiation from its parent star as the planet Venus receives from our Sun, with the latter having a very thick carbon dioxide atmosphere. This study comes after a June 2023 study published in Nature used data from NASA’s James Webb Space Telescope (JWST) to ascertain that TRAPPIST-1c does not possess a carbon dioxide atmosphere. Both studies come as the TRAPPIST-1 system, which is located approximately 41 light-years from Earth and orbits its star in just 2.4 days, has received a lot of attention from the scientific community in the last few years due to the number of confirmed exoplanets within the system and their potential for astrobiology purposes.

December 29, 2023December 29, 2023 by Carolyn Collins Petersen

Organic Molecules Come from the Universe’s Cold Places

Asteroid Ryugu contains organic molecules called polycyclic aromatic hydrocarbons, thought to be chemical building blocks for life. Courtesy ISAS/JAXA — Asteroid Ryugu as seen by Japan's Hayabusa 2 spacecraft, which returned a sample of the ancient asteroid to Earth in 2020. Image Courtesy ISAS/JAXA

Life, as we all know, is based on chemistry. Prebiotic chemical building blocks existed on our planet for a long time before life arose. Astrobiology and cosmochemistry focus on the formation of those building blocks. They also look at the role each played in creating all the life forms we know today.