Universe Today

November 28, 2023November 28, 2023 by Mark Thompson

Telescopes Didn’t Always Play Nicely with Each Other. That’s About to Change

This composite image of the GOODS-South field — the result of an extremely deep survey using two of the four giant 8.2-metre telescopes composing ESO’s Very Large Telescope (VLT) and a unique custom-built filter — shows some of the faintest galaxies ever seen. — Composite image of the GOODS-South field, result of a deep survey using two 8.2-metre telescopes (Credit : ESO/M Hayes)

Those readers who have dabbled with astronomical imaging will be familiar with the technique of taking multiple images and then stacking them together to improve the strength of the signal, yielding better images. Taking this technique further many research projects require date of the same object spanning longer time frames than a nights observing. This data is usually captured from different locations and under different conditions. The problem has been matching the observations across all these survey runs. Researchers have shared a new approach to calculate if separate images of the same object will yield additional signals or just generate useless noise.

November 28, 2023November 28, 2023 by Mark Thompson

A Tiny Quadcopter Could Gather Rocks for China’s Sample Return Mission

Mars Ingenuity helicopter on the surface of Mars — Image of the Mars Ingenuity helicopter (Source : NASA)

Space exploration is always changing. Before February 2021 there had never been a human made craft flying around in the atmosphere of another world (other than rocket propelled landers arriving or departing). The Mars Perseverance rover changed that, carrying with it what can only be described as a drone named Ingenuity. It revolutionised planetary exploration and now, China are getting in on the act with a proposed quadcopter for a Mars sample return mission.

November 28, 2023November 28, 2023 by Evan Gough

JWST Reveals a Newly-Forming Double Protostar

This new Picture of the Month from the NASA/ESA/CSA James Webb Space Telescope reveals intricate details of the Herbig Haro object 797 (HH 797). HH 797 dominates the lower half of this image. The bright infrared objects in the upper portion of the image are thought to host two further protostars. This image was captured with Webb’s Near-InfraRed Camera (NIRCam). Image Credit: JWST/CSA/ESA/NASA

As our newest, most perceptive eye on the ongoing unfolding of the cosmos, the James Webb Space Telescope is revealing many things that were previously unseeable. One of the space telescope’s science goals is to expand our understanding of how stars form. The JWST has the power to see into the cocoons of gas and dust that hide young protostars.

It peered inside one of these cocoons and showed us that what we thought was a single star is actually a binary star.

November 28, 2023November 28, 2023 by Matt Williams

Why Don't We See Robotic Civilizations Rapidly Expanding Across the Universe?

The central region of the Milky Way, also known as the Zone of Avoidance. Credit: ESO/S. Brunier

In 1950, while sitting down to lunch with colleagues at the Los Alamos Laboratory, famed physicist and nuclear scientist Enrico Fermi asked his famous question: “Where is Everybody?” In short, Fermi was addressing the all-important question that has plagued human minds since they first realized planet Earth was merely a speck in an infinite Universe. Given the size and age of the Universe and the way the ingredients for life are seemingly everywhere in abundance, why haven’t we found any evidence of intelligent life beyond Earth?

This question has spawned countless proposed resolutions since Fermi’s time, including the infamous Hart-Tipler Conjecture (i.e., they don’t exist). Other interpretations emphasize how space travel is hard and extremely time and energy-consuming, which is why species are likely to settle in clusters (rather than a galactic empire) and how we are more likely to find examples of their technology (probes and AI) rather than a species itself. In a recent study, mathematician Daniel Vallstrom examined how artificial intelligence might be similarly motivated to avoid spreading across the galaxy, thus explaining why we haven’t seen them either!

November 28, 2023November 28, 2023 by Evan Gough

The Second Most Energetic Cosmic Ray Ever Found

An example of a cosmic-ray extensive air shower recorded by the Subaru Telescope. The highlighted tracks, which are mostly aligned in similar directions, show the shower particles induced from a high-energy cosmic ray. Credit: NAOJ/Hyper Suprime-Cam (HSC) Collaboration

“Oh My God,” someone must have said in 1991 when researchers detected the most energetic cosmic ray ever to strike Earth. Those three words were adopted as the name for the phenomenon: the Oh-My-God particle. Where did it come from?

November 27, 2023November 27, 2023 by Mark Thompson

If Warp Drives are Impossible, Maybe Faster Than Light Communication is Still on the Table?

Artist impression of a starship with warp drive (Credit : Alorin)

I’m sure many readers of Universe Today are like me, fans of the science fiction genre. From the light sabres of Star Wars to the neuralyzer of Men in Black, science fiction has crazy inventions aplenty and once science fiction writers dream it, scientists and engineers try and create it. Perhaps the holy grail of science fiction creations is the warp drive from Star Trek and it is fair to say that many have tried to work out if it is even possible to travel faster than the speed of light. To date, alas, to no avail but if the warp drive eludes us, what about faster than light communication!

November 27, 2023November 27, 2023 by Mark Thompson

For its Next Trick, Gaia Could Help Detect Background Gravitational Waves in the Universe

Artist impression of ESA's Gaia satellite observing the Milky Way. The background image of the sky is compiled from data from more than 1.8 billion stars. It shows the total brightness and colour of stars observed by Gaia — Artist impression of ESA's Gaia satellite observing the Milky Way (Credit : ESA/ATG medialab; Milky Way: ESA/Gaia/DPAC)

Ripples in a pond can be captivating on a nice sunny day as can ripples in the very fabric of space, although the latter are a little harder to observe. Using the highly tuned Gaia probe, a team of astronomers propose that it might just be possible to detect gravitational waves through the disturbance they impart on the movement of asteroids in our Solar System!

November 27, 2023November 27, 2023 by Evan Gough

Vampire Stars Get Help from a Third Star to Feed

Artist’s impression composed of a star with a disc around it (a Be “vampire” star; foreground) and its companion star that has been stripped of its outer parts (background). Credit: ESO/L. Calçada

Some stars are stuck in bad binary relationships. A massive primary star feeds on its smaller companion, sucking gas from the companion and adding it to its own mass while diminishing its unfortunate partner. These vampire stars are called Be stars, and up until now, astronomers thought they existed in binary relationships.

But new research shows that these stars are only able to feed on their diminutive neighbour because of a third star present in the system.

November 27, 2023November 27, 2023 by Nancy Atkinson

Simulating a Piece of Space Junk

A graphic which depicts simulating a satellite's death spiral. ESA/University of Bern.

When a spacecraft dies, it loses the ability to maintain its direction in space. Additionally, as the spacecraft’s orbit begins to decay, the thin atmosphere interacts with the spacecraft, causing it to tumble unpredictably. ESA’s Clean Space Initiative hopes to remove the most hazardous space debris. This means capturing dead satellites that are in a death spiral. To help begin the project Researchers observed over 20 objects in space over two year and then recreated their spin to develop plans to retrieve them.

Retrieving a tumbling spacecraft will require a brave robot to take on the task!

November 27, 2023November 29, 2023 by Nancy Atkinson

Aerocapture is a Free Lunch in Space Exploration

Visualisation of the ExoMars Trace Gas Orbiter aerobraking at Mars. Credit: ESA/ATG medialab.

This article was updated on 11/28/23

When spacecraft return to Earth, they don’t need to shed all their velocity by firing retro-rockets. Instead, they use the atmosphere as a brake to slow down for a soft landing. Every planet in the Solar System except Mercury has enough of an atmosphere to allow aerocapture maneuvers, and could allow high-speed exploration missions. A new paper looks at the different worlds and how a spacecraft must fly to take advantage of this “free lunch” to slow down at the destination.