Space and Astronomy News for the 22nd of March 2025

The BIG space news this week has been the return to Earth of the two NASA astronauts, Suni Williams and Butch Wilmore, who took the initial  Boeing Starliner capsule for what was supposed to be an eight day mission that turned into a nine month long sojourn aboard the ISS (International Space Station). 

There were a few folks wondering that if astronauts like these need to be stretchered off their spacecraft after landing, following months in space, how are Mars astronauts going to function after landing when they've spent 7-9 months travelling to the red planet?  It's something that's often seen when astronauts return from extended stays in space.

NASA Astronaut Sunni Williams following her splashdown this week. Image via NASA

BINTEL had a chat with the Dr. Jon Clarke, president of the Mars Society Australia about this:

"The footage is a bit misleading.  I had several conversations with a regular visitor to Australia,  Dr Vadim Gushin of the Institute of Bio-Medical Problems in Moscow, about this topic. 

If the astronauts do their exercises they have no major problems, despite some muscle wastage, bone density loss, and obviously the need to readjust their vestibular systems. 

Case in point, Shannon Lucid, who walked down the Shuttle stairs after six months on Mir, or the Russian cosmonauts such Musa Manarov who at the post flight media conference when asked how he felt after a record stint in orbit, did a one-arm handstand."

This means astronauts are likely to be back on their feet and ready to explore the Martian surface not long after landing, even after their long journey. 

"That said, they are often a bit wobbly, which is why they keep them seated. The medicos, according to Dr Vadim, also want to keep them as inactive as possible for their preliminary assessment to be as close to in space conditions as possible." continued Dr. Clarke. 

JWST (James Webb Space Telescope) photographs four giant planets around the young large star, HR 8799.

Astronomers have known for some years that HR 8799 is the home to a number of planets.  The first of these were discovered  in the infrared part of the spectrum with the Keck and Gemini telescopes in Hawaii. 

Now the JWST has directly photographed the four giant planets orbiting HR 8799.

The four planets around HR 8799 shown are above. Please note this is a direct image of them taken with the JWST, not an illustration or computer simulation. The "star" over HR 8799 blocks the light from the star itself to help image the much dimmer planets. 

Astronomers also found evidence of carbon dioxide in these planets' atmospheres, indicating they were formed much like our local gas giants Jupiter and Saturn. A smaller, solid core gradually attracted gas over time. You can read more about this fascinating discovery here.

Four planets found around the second closest star to Earth

Most people would know that Alpha Centauri is the closest "star" to Earth. It's visible as the lower of the two pointers to Southern Cross and shines with a slight yellowish colour. Even a small telescope will show that Alpha Centauri is a double star, with two bright stars close together in the eyepiece. There's a much fainter companion to these two - Proxima Centauri, which can't be spotted so easily.  

The closest single star system, or what could be described as the "second closest star to Earth" is called Barnard's Star. This is a small red-dwarf, much smaller and cooler than our Sun, and more than twice its age at over 10 billion years old. It was discovered by E. E. Barnard at Yerkes Observatory in 1916 - and we've now been trying to find planets around it for over a hundred years.

An illustration of Barnard's Star as seen from one of its planets. International Gemini Observatory/NOIRLab/NSF/AURA/P. Marenfeld

There's been some debate over the years about whether Barnard's Star has any planets orbiting around it, however new results from Gemini North telescope in Hawaii have now identified four rocky planets.  These are all much smaller than the Earth, orbit quickly around Barnard's Star, and all are also far too hot to support life like we know it on Earth.  

These new planets were found using a technique called radial velocity method, which measures extremely small "wobbles" in the host star's movement which allows astronomers to not only infer the existence of planets, but also confirms their number and even their mass. There's a full press release here that goes into the new discovery in more detail.

These newly discovered exoplanets have not been observed directly, and are beyond the current imaging capabilities of any Earth or space based telescope. 

First images from the world's largest radio telescope: it works but it's just getting going.

The Square Kilometre Array (SKA) Observatory hopes to make major contributions to our knowledge of some of the "big" questions about the Universe, including the formation and evolution of galaxies, fundamental physics in extreme environments, even exploring the origins of life.

Still under construction at sites in Australia and South Africa, it will eventually consist of  hundreds of dishes and thousands of antennas. The SKAO’s facilities will be the two most advanced radio telescopes on Earth.

The first image from an early working version of the SKA-Low telescope, using just 1,024 of the planned 131,072 antennas. The bright "stars" are in fact distant galaxies. The Full Moon is shown to indicate how much of the sky is contained. 

The project this week released a wide field image taken using only a small percentage of SKA-Low's final capabilities.

SKA-Low is one of two telescopes under construction by the SKA Observatory (SKAO) and is located in Western Australia. 

This new image covers an area of some 25 square degrees or about as much as 100 full Moon. It shows around 85 of the brightest galaxies in that part of the sky, however it's only an initial test.

Sebastian Neuweiler from the SKAO and CSIRO told BINTEL:

"The first image was produced using data collected from the first four connected SKA-Low stations, which together comprise 1,024 of the eventual 131,072 antennas of SKA-Low, spread over a distance of just under 6 km."
 
"By 2026/2027, another 16,000 antennas will make SKA-Low the most sensitive radio telescope of its kind in the world and enable it to detect over 4,500 galaxies in the same area of the sky."
 
"By 2028/2029, SKA-Low will count over 78,000 antennas and be able to detect more than 23,000 galaxies in this field. The full SKA-Low telescope will count more than 130,000 antennas, spread over 74 km. Deep surveys performed of this area of the sky from 2030 will be able to reveal up to 600,000 galaxies."

SKA-Low Lead Commissioning Scientist Dr George Heald commented:

“The quality of this image was even beyond what we hoped for using such an early version of the telescope,” Dr Heald said. 

“The bright galaxies we can see in this image are just the tip of iceberg. With the full telescope we will have the sensitivity to reveal the faintest and most distant galaxies, back to the early Universe when the first stars and galaxies started to form. This is technically difficult work and the first step to unlocking the awesome science that will be possible.”  

Read more via the SKAO website here as well as an excellent article at The Conversation here. 

It's staggering to think what we'll learn when this magnificent facility is completed in 2029. 

Cheers,

Earl White 

BINTEL

22nd March  2025