Universe Today

November 6, 2023November 6, 2023 by Alan Boyle

Get a Reality Check on Plans to Build Cities in Space

Illustration: Scene showing "For All Mankind" city on Mars from above — A scene from "For All Mankind" shows a fictional Martian city from above. (Credit: Sony Pictures / Apple TV+)

Elon Musk and Jeff Bezos may harbor multibillion-dollar dreams of sending millions of people to live on Mars, on the moon and inside free-flying space habitats — but a newly published book provides a prudent piece of advice: Don’t go too boldly.

It’s advice that Kelly and Zach Weinersmith didn’t expect they’d be giving when they began to work on their book, titled “A City on Mars.” They thought they’d be writing a guide to the golden age of space settlement that Musk and Bezos were promising.

“We ended up doing a ton of research on space settlements from just every angle you can imagine,” Zach Weinersmith says in the latest episode of the Fiction Science podcast. “This was a four-year research project. And about two and a half years in, we went from being fairly optimistic about it as a desirable, near-term likely possibility [to] probably unlikely in the near term, and possibly undesirable in the near term. So it was quite a change. Slightly traumatic, I would say.”

November 6, 2023November 6, 2023 by Mark Thompson

Oops. Astronauts Lost a Tool Bag During a Spacewalk!

NASA astronauts Jasmin Moghbeli (top) and Loral O’Hara (bottom) team up during their first spacewalk for maintenance on the outside of the space station. Credit: NASA TV — NASA Astronauts Jasmin Moghbeli (top) and Loral O'Hara (bottom)

I know for a fact it’s one of the most annoying things that can happen. I’ve done it lots; whether that be out at night with telescope or a bit of DIY but for sure it has to rate as one of the most frustrating things to happen. I am talking of dropping something you are using. Ranking high is dropping tools while you are actually using them.. Dropping a tool is one thing but imagine dropping an entire bag of tools, while in orbit!!!! Oops!

November 6, 2023November 6, 2023 by Evan Gough

This is a First. An Exoplanet in a Polar Circumbinary Disc Surrounding Two Stars.

This illustration shows a binary star surrounded by a thick disc of material in a polar orbit. Copyright and credit: University of Warwick/Mark Garlick

We live in an age of exoplanet discovery. One thing we’ve learned is not to be surprised by the kinds of exoplanets we keep discovering. We’ve discovered planets where it might rain glass or even iron, planets that are the rocky core remnants of gas giants stripped of their atmospheres, and drifting rogue planets untethered to any star.

November 6, 2023November 6, 2023 by Matt Williams

Juno Spots Salts and Organic Molecules on Ganymede’s Surface

Enhanced image of Ganymede taken by the JunoCam during the mission's flyby on June 7th, 2021. Credit: NASA/JPL-Caltech/SwRI/MSSS/Kalleheikki Kannisto

NASA’s Juno mission continues to orbit Jupiter, gathering data on its atmosphere, composition, gravitational field, magnetic field, and radiation environment. This data is helping scientists to learn more about the planet’s formation, internal structure, mass distribution, and what is driving its powerful winds. Periodically, the spacecraft also performs flybys of Jupiter’s largest satellites (the Galilean Moons), acquiring stunning images and vital data on their surfaces. These include optical and thermal images of Io’s many active volcanoes, Europa’s icy terrain, and infrared images of Ganymede.

During its last flyby of Ganymede (June 7th, 2021), Juno collected infrared images and spectra on the moon’s surface using its Jovian InfraRed Auroral Mapper (JIRAM) instrument. According to a recent study by an international team of researchers, this data revealed the presence of salt minerals and organic molecules on the icy moon’s surface. The findings could help scientists better understand the origin of Ganymede, the composition of its interior ocean, and the way material is exchanged between the surface and interior. In short, it could help scientists determine if life exists deep inside Ganymede’s ocean.

November 6, 2023November 3, 2023 by Laurence Tognetti

JWST Detects Carbon Dioxide in a Centaur for the First Time

Centaurs are small planetary bodies that orbit between Jupiter and Neptune and have baffled astronomers for sharing characteristics with both asteroids and comets. Centaurs got their name after the mythical half-horse, half-human creatures called centaurs due to their dual characteristics. Above is an artist's illustration displaying a centaur creature among asteroids (left) and comets (right). (Credit: NASA/JPL-Caltech)

A study published today in The Planetary Science Journal examines how NASA’s James Webb Space Telescope (JWST) has conducted a first-time detection of carbon dioxide in a Centaur, this one designated 39P/Oterma. A Centaur is a small planetary body that orbits between Jupiter and Neptune and frequently crosses the orbits of one or more of the gas giant planets within our solar system. While no Centaur has been imaged up-close, they typically exhibit a combination of attributes between comets and asteroids. While carbon monoxide has been detected in two known centaurs, this recent discovery could mark a turning point in how scientists understand the formation, evolution, and composition of not only Centaurs, but of the early solar system, as well.

November 6, 2023November 6, 2023 by Evan Gough

Roman Could Finally Tell Us if Primordial Black Holes Exist

An image based on a supercomputer simulation of the cosmological environment where primordial gas undergoes the direct collapse to a black hole. Credit: Aaron Smith/TACC/UT-Austin. — An image based on a supercomputer simulation of the cosmological environment where primordial gas undergoes the direct collapse to create black holes. Credit: Aaron Smith/TACC/UT-Austin.

When the Universe erupted into existence with the Big Bang, all of its matter was compressed into a tiny area. Cosmologists theorize that in some regions, subatomic matter may have been so tightly packed that matter collapsed into primordial black holes. If these primordial black holes exist, they’re small, and they could be hiding among the population of free-floating planets.

November 6, 2023November 9, 2023 by Matt Williams

Supermassive Black Holes Shut Down Star Formation During Cosmic Noon

Artist’s impression of a quasar. These all have supermassive black holes at their hearts. Credit: NOIRLab/NSF/AURA/J. da Silva

Since it became operational almost two years ago, the James Webb Space Telescope (JWST) has produced countless breathtaking images of the Universe and enabled fresh insights into how it evolved. In particular, the telescope’s instruments are optimized for studying the cosmological epoch known as Cosmic Dawn, ca. 50 million to one billion years after the Big Bang when the first stars, black holes, and galaxies in the Universe formed. However, astronomers are also getting a better look at the epoch that followed, Cosmic Noon, which lasted from 2 to 3 billion years after the Big Bang.

During this time, the first galaxies grew considerably, most stars in the Universe formed, and many galaxies with supermassive black holes (SMBHs) at their centers became incredibly luminous quasars. Scientists have been eager to get a better look at galaxies dated to this period so they can see how SMBHs affected star formation in young galaxies. Using near-infrared data obtained by Webb, an international team of astronomers made detailed observations of over 100 galaxies as they appeared 2 to 4 billion years after the Big Bang, coinciding with Cosmic Noon.

November 4, 2023November 4, 2023 by Mark Thompson

Searching for the Supernova Neutrino Background to the Universe

Hubble Space Telescope image of supernova 1994D in galaxy NGC 4526.

It’s a sobering statement that stars like the Sun, more accurately ALL stars will die eventually, yes even the Sun! Don’t panic though, we still have a good few billion years to go so you will get to the end of this article. The more massive stars die as the dramatic supernovae explosions and when they do, they send a burst of neutrinos across the Universe. Astronomers now think it’s likely there is a background of neutrinos across the cosmos and that one day we will be able to map the historical distribution of supernova explosions, may be even by 2035.

November 4, 2023November 13, 2023 by Matt Williams

Civilizations Could Use Gravitational Lenses to Transmit Power From Star to Star

A new study shows how Solar Gravitational Lenses (SGLs) could be used to beam power from one system to another.. Credit: NASA/ESA

In 1916, famed theoretical physicist Albert Einstein put the finishing touches on his Theory of General Relativity, a geometric theory for how gravity alters the curvature of spacetime. The revolutionary theory remains foundational to our models of how the Universe formed and evolved. One of the many things GR predicted was what is known as gravitational lenses, where objects with massive gravitational fields will distort and magnify light coming from more distant objects. Astronomers have used lenses to conduct deep-field observations and see farther into space.

In recent years, scientists like Claudio Maccone and Slava Turyshev have explored how using our Sun as a Solar Gravity Lens (SGL) could have tremendous applications for astronomy and the Search for Extratterstiral Intelligence (SETI). Two notable examples include studying exoplanets in extreme detail or creating an interstellar communication network (a “galactic internet”). In a recent paper, Turyshev proposes how advanced civilizations could use stellar gravitational lenses to transmit power from star to star – a possibility that could have significant implications in our search for technosignatures.

November 4, 2023November 4, 2023 by Scott Alan Johnston

Dimorphos is Probably a Piece of Didymos

Last September, NASA purposefully smashed a spacecraft into Dimorphos, a 160m-wide space rock orbiting a larger asteroid named Didymos. The goal of the mission, called DART (the Double Asteroid Redirection Test), was to demonstrate humanity’s ability to redirect hazardous asteroids away from Earth. That part of the mission was a success above and beyond all expectations. But now scientists are also learning more about the origins of the two asteroids. A study conducted in the wake of the DART impact found that Dimorphos is made from the same material as Didymos, and that the pair of asteroids likely originated from a single body.