October 3, 2025 Zimmerman/Batchelor podcast
Embedded below the fold in two parts.
To listen to all of John Batchelor’s podcasts, go here.
» Read more
Very brief descriptions, with appropriate links, of current or recent news items.
Embedded below the fold in two parts.
To listen to all of John Batchelor’s podcasts, go here.
» Read more
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.
SpaceX this morning successfully launched another 28 Starlink satellites, its Falcon 9 rocket lifting off from Vandenberg Space Force Base in California.
The first stage completed its second flight, landing on a drone ship in the Pacific.
The leaders in the 2025 launch race:
127 SpaceX
58 China
13 Russia
12 Rocket Lab
SpaceX still leads the rest of the world in successful launches, 127 to 98.
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

Jazz inspecting her new domain.
Posting has been relatively light this week for two reasons.
First, I am in the process of switching to a new computer, and getting it properly configured to my very complex requirements (which include a keyboard that matches the old RadioShack TRS-80 Model III) has been time consuming. Progress is being made, but with Linux there are always glitches than need fixing.
Second and more important, Diane and I adopted a new kitten this week, as shown in the picture to the right. We have named her Jazz, and getting her acclimated has required a bit of work, especially because our older cat Molly seems unhappy about the change (Nothing but hisses, which I think will fade with time). Things are improving but it does take me from work.
We hope this new family member will fill the hole when our tabby Misty disappeared in June, likely grabbed by a predator. So far it appears Jazz will do the job.
It is the start of the month, which means it is time for my monthly sunspot update, using NOAA’s own monthly update of its graph of sunspot activity and annotating it with extra information to illustrate the larger scientific context.
This graph is below, with the green dot showing the sunspot number for activity on the Sun’s Earth-facing hemisphere in September. As you can see, the count closely matched the April 2025 prediction by NOAA’s panel of solar scientists, which posited that the Sun was finally beginning its ramp down from solar maximum (as indicated by the purple/magenta line).
» Read more
The satellite propulsion startup Portal has become the first commercial company to test successfully a thruster that uses concentrated sunlight to ionize a fuel.
The concept has been studied several times by NASA and other government entities, but never tested to a point where it could be used on a mission. According to this report:
For the vacuum chamber test at Portal’s Bothell lab, engineers used an electrical induction system to simulate the sun’s heating power. The apparatus reached temperatures in the range of 1,500 degrees Celsius (2,700 degrees Fahrenheit), and the performance of the thruster validated Portal’s propulsion architecture for integration with future flight hardware.
The concept is similar to an ion engine, but appears to produce more thrust, allowing it to move satellites more quickly to different orbits. Portal hopes to do an in orbitat test by next year. The company has raised $17.5 million in private funding, and $45 million from an Air Force grant.
Link here. The key take-away is that nothing is being repurposed to attempt to fly to Comet 3I/Atlas. Instead, as expected the science teams for all the Mars orbiters will turn their instruments to the comet when it is at its closest point to Mars, about 19 million miles away.
Don’t expect any Earth-shattering revelations:
The cameras on these spacecraft were designed to photograph the surface of Mars from Mars orbit, and won’t be able to pick out much detail on such a relatively small comet 30 million km away. But the cameras may be able to capture images of its long tail and also gather data that scientists can use to find out more about what 3I/ATLAS is made of.
Some spectroscopic data will be obtained, but it likely will not be much better than what Webb and other Earth-based telescopes have gotten already.
Similarly, the science team for Europe’s Juice mission, on its way to Jupiter, will take a look, but the distances and orbital positioning will likely limit what it can detect as well.
Embedded below the fold in two parts.
To listen to all of John Batchelor’s podcasts, go here.
» Read more
Courtesy of BtB’s stringer Jay. This post is also an open thread. I welcome my readers to post any comments or additional links relating to any space issues, even if unrelated to the links below.

Climate activist Michael Mann
Though he has claimed to be a climate scientist for decades, Michael Mann at the University of Pennsylvania has been proven time and again to merely be a leftwing global-warming activist, faking data to make it appear the increase of carbon dioxide in the atmosphere is causing global warming, falsely claiming he was a Nobel laureate winner, and acting to destroy the careers of anyone who challenged the veracity of his research.
Sadly, when these facts were discovered almost two decades ago, about the time the climategate emails were released, the climate science community ignored the facts (a very bad thing for scientists to do) and acted to defend Mann. Thus he was able to continue to publish while keeping his job as a professor in academia, first at Pennsylvania State University and then at the University of Pennsylvania.
Mann’s ability to survive fraud and abuse of power however has finally come to an end, and it did so because he decided to go on line after Charlie Kirk was assassinated to joke about that murder and to slander Kirk by reposting comments that called Kirk “head of Trump’s Hitler Youth.”
Though Mann subsequently denied that was what he was doing, deleting some of his worst tweets while claiming to condemn such violence, it appears no one believes him. As a result, he announced yesterday that he resigning his position at Pennsylvania University in order to become a full time political activist. From his resignation statement:
» Read more
The uncertainty of science: A review of the population of what scientists call “Little Red Dots” (LRDs) — discovered in the early universe by the Webb Space Telescope — has found that 30% do not appear to be compact objects when viewed in ultraviolet wavelengths.
The team studied 99 LRDs, and found that about 30% are not simply compact dots when observed in the ultraviolet.Instead, they reveal disturbed or clumpy structures, in stark contrast to their smooth, point-like appearance at optical wavelengths. Because these galaxies are so far away, their optical light is stretched, or “redshifted,” into the long-wavelength channel of JWST, where the resolution is not sharp enough to see structure, so they look like simple dots.
Rinaldi: ‘But their ultraviolet light is shifted into JWST’s short-wavelength channel, where the telescope has much finer resolution, and there we suddenly see clumps, asymmetries, and signs of interaction. On top of this, in the spectra of some of our LRDs we directly detect the fingerprints of active black holes, with gas moving at thousands of kilometres per second.’ This shows that at least part of this population is powered by growing black holes, while others seem to be dominated by star formation, making LRDs a mixed and diverse family of sources. This is a crucial clue, suggesting that mergers and galaxy interactions may be the trigger for the “LRD phase”.
In other words, astronomers don’t really know what these dots are at present. If some are supermassive black holes, this poses a problem for Big Bang cosmology, as there should not have been enough time since the Big Bang for these black holes to have formed.
That 70% still appear to be compact single objects might mean that’s what they are, but it could also mean that our present observations tools don’t yet have the ability to resolve them.