Space and Astronomy News for the 23rd of August 2025

As usual, lots of space and astronomy news this week!

Uranus gets a new moon

We might think of the JWST (James Webb Space Telescope) making observations deep into interstellar and intergalactic space, but it's also making discoveries somewhat closer to home. 

During an observing run on the 2nd of February, 2025, Webb captured a previously undiscovered moon around the ice giant, Uranus. This brings the total of known moons at the planet to 29. The newly discovered moon is only approx. 10km across. Uranus has been extensively observed by ground based telescopes for many years and even visited by spacecraft. The small size meant it remained hidden until now. 

“This object was spotted in a series of 10 40-minute long-exposure images captured by the Near-Infrared Camera (NIRCam),” said Maryame El Moutamid, a lead scientist in SwRI’s Solar System Science and Exploration Division based in Boulder, Colorado. “It’s a small moon but a significant discovery, which is something that even NASA’s Voyager 2 spacecraft didn’t see during its flyby nearly 40 years ago.”

While the name S/2025 U1 isn't too fancy, all of the moons around Uranus have been named after characters from Shakespearian plays, so we expect something fitting will be assigned to it soon. 

Even with charts showing its position, S/2025 U1 will be too small to observe with your telescope. 

More details at the NASA website here.

Did comets help make life Earth *the* place for life?

The water found on Comet 12P/Pons-Brooks is found to be very similar to what's in our oceans.

Many folks would know that there water and ice are found on comets. It has long been conjectured that comets were one mechanism that delivered the large amounts of water found on the Earth's surface, mainly in our oceans. 

While we observe water on comets, is it the same water we see around us? (Bear in mind I'm writing this during a long and very wet weather spell here in Sydney!) 

For starters, water isn't just water. We all know that water is a compound of two common elements: two hydrogen molecules and one oxygen. This is why it's also called "H2O".  There's also a compound called heavy water, "HDO". This is formed by the same number of molecules with the exception of the hydrogen being a heavier isotope called deuterium which has a neutron. This is lacking in "normal" hydrogen. 

Heavy water is found in small amounts on Earth, mixed in with regular water.  

Astronomers have now observed the water on a Halley class comet 12P/Pons-Brooks to have an almost identical amount of heavy water as the water we find in our oceans.  Observations with the Atacama Large Millimeter/submillimeter Array (ALMA) mapped the ratio of "normal" water and heavy water in the comet as it got close to the Sun.

Lead researcher, Martin Cordiner of NASA’s Goddard Space Flight Center, commented:

"Comets like this are frozen relics left over from the birth of our Solar System 4.5 billion years ago. Since Earth is believed to have formed from materials lacking water, comet impacts have long been suggested as a source of Earth’s water. Our new results provide the strongest evidence yet that at least some Halley-type comets carried water with the same isotopic signature as that found on Earth, supporting the idea that comets could have helped make our planet habitable.”

While it's not definitive, these fascinating results help bolster the theory that much of the water on Earth where life grew and evolved, was delivered from space by comets.

Read more here.

SpaceX Starship's next flight this week

The largest rocket ever to fly is going to fly again. Maybe.

SpaceX have announced they've finalised investigations into the causes of the failures of the last Starship mission and are now ready to launch Starship 10 this coming Sunday the 24th of August 2025 from 6.30pm US central time.  (From Monday morning 25th of August 9.30am Sydney time.)

You can follow the live broadcast here from a little before via this link.

This is again a test flight and not aimed at placing any payload into Earth orbit. Rather, it's focused on testing hardware including engine restarts and thermal characteristics. Neither the booster nor Starship itself will be returned to the launch pad for an attempted "chopsticks" catch and landing. Both will splash down into the ocean, assuming the flight is successful.

You can read a detailed mission profile here.

We will report back next week with the results of this test. It will be spectacular no matter what the results. 

The first launch of the SpaceX Starship was nearly two and a half years ago and it's yet to reach orbit. By contrast, Blue Origin's mega rocket, the New Glenn, is headed to Mars with the twin probes of NASA's ESCAPADE mission as some point from September 29th, 2025 onwards. (This will be the second launch of New Glenn, following its first successful launch in January 2025.)

More to come on that mission soon!

Cheers,

Earl White 

BINTEL 

23rd August 2025