Author: Robert Zimmerman

FAA: No Starship/Superheavy launch before late November

9:01 am

In response to speculation that the fifth Starship/Superheavy test launch could happen in mid-October — based on a recent notice to mariners from the Coast Guard, the FAA on Wednesday made it clear that its stonewalling of SpaceX will continue.

“We are not issuing launch authorization for a launch to occur in the next two weeks — it’s not happening,” an FAA spokesman said Wednesday afternoon. “Late November is still our target date.”

The report comes from the San-Antonio Express-News, and as is typical of the reporting in the propaganda press, the article only gives the FAA’s side of this story, making absolutely no mention of SpaceX’s detailed and very public objections. As far as this news outlet is concerned, the FAA is god, whatever it says must be true. So much for a skeptical free press whose goal is supposed to be to hold government accountable.

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ULA successfully completes second test launch of its new Vulcan rocket

8:36 am

ULA this morning successfully completed the second test launch of its new Vulcan rocket, lifting off from Cape Canaveral from Florida.

It placed a dummy test payload into orbit in order to obtain from the Space Force certification that will allow the company to begin operational military launches and actually make money from the rocket. ULA hopes to launch two such Vulcan launches before the end of the year, and then hopes to do ten more Vulcan launches in 2025, along with ten Atlas-5 launches as it closes out that rocket’s inventory before retiring it.

UPDATE: An explosion on of Vulcun’s two solid-fueled strap-on boosters during the launch today might prevent a quick certification from the military. Though the rocket successfully put the payload into its correct orbit, it appears the nozzle failed on that booster, throwing it out sideways, fortunately away from the rocket. The video here shows this clearly. I was startled by this explosion during the launch, but then forgot about it (until my readers reminded me) when the payload reached orbit as planned.

The strap-on boosters are manufactured by Northrop Grumman. Before using them again ULA needs to get clarity on this issue. We also must wonder if the FAA will step in as it has for SpaceX to ground ULA. At the moment it has decided not to do so.

This was ULA’s fifth launch in 2024, so there is no change in the 2024 launch race leader board.

95 SpaceX
44 China
11 Russia
11 Rocket Lab

American private enterprise now leads the rest of the world combined in successful launches 112 to 67, while SpaceX by itself now leads the entire world, including American companies, 95 to 84.

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Van Halen – Jump

6:01 pm

An evening pause: Its an “official video,” so much of this is lip synched footage cobbled together to make what looks like a single performance. Much of it however is the actual performance, and the song is good.

Hat tip James Street.

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October 3, 2024 Quick space links

3:29 pm

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.

  • Major solar flare in progress
    As Jay notes, “Regular news outlets are picking this up with the usual apocalypse chatter.” The big issue is how this might effect emergency communications using ham radio.
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Pushback: Fired teacher wins $575K free speech settlement from school board

2:06 pm

Peter Vlaming, fired for his opinions
Peter Vlaming

Fight! Fight! Fight! In 2018 Peter Vlaming, a long time French teacher in the West Point School District in Virgina was fired because he would not use the preferred pro-nouns of one of his students. The firing was especially offensive in that Vlaming had done everything reasonable to accommodate the student, including using her preferred male-sounding name while avoiding the use of pronouns. He just could not use male pronouns for a female student. It violated his core beliefs.

The school board considered his silence on this point abusive to the student, and fired him. In 2019 he sued, and on September 30, 2024 his attorneys from the non-profit legal firm, the Alliance Defending Freedom, won him a $575K settlement from school board.

[T]he West Point School Board has agreed to pay $575,000 in damages and attorneys’ fees. In addition, the school board cleared Peter Vlaming’s firing from his record, and separate from the settlement agreement, changed its policies to conform to the new Virginia education policies established by Gov. Glenn Youngkin that respect fundamental free speech and parental rights.

» Read more

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ULA’s big plans for 2025

12:31 pm

As ULA prepares for the second launch of its new Vulcan rocket, presently scheduled for launch tomorrow at 6 am (Eastern), it held a press briefing on October 2, 2024 to provide an update on the rocket’s present and future status.

The key takeaways, assuming this launch succeeds as planned, as noted in a tweet by reporter Jeff Foust from Space News:

  • ULA still plans on completing two national security Vulcan flights before the end of the year
  • It is targeting 20 launches in 2025, half with Vulcan and half with Atlas-5
  • The first Atlas-5 launch of Amazon’s Kuiper satellites won’t happen until 2025
  • When Sierra Space says Dream Chaser is ready, ULA will launch it

Completing three Vulcan launches in the next three months will almost match the four launches the company has so far completed in the first nine months of the year. Furthermore, considering that ULA’s previous record for launches in a single year is 16, set in 2009, and that the company has not completed more than ten launches in a year since 2016, these plans are very ambitious indeed.

If it succeeds however in just getting close to these numbers, ULA will be doing very well indeed.

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A new map of the magnetosphere of Mercury

12:11 pm

Map of Mercury's magnetosphere
Click for original.

Using data obtained during the June 2023 fly-by by the European-Japanese probe BepiColombo, scientists have now published a new detailed map of the magnetic field that surrounds Mercury.

That map is to the right. From the caption:

A textured sphere representing Mercury is shown with magnetic field lines compressed on the sunward side and streaming out into a tail on the nightside. The BepiColombo spacecraft’s trajectory is drawn passing through the magnetosphere from dawn to dusk, close to the planet’s surface. Various features in the magnetosphere are depicted and labelled with text. Following the order in which they were detected by the spacecraft, this includes the bow shock, magnetopause, low-latitude boundary layer, cold ion cloud, plasma sheet horn and ring current.

You can read the peer-reviewed paper here [pdf]. Note that this research does not include data obtained during BepiColumbo’s fourth fly-by of Mercury in September. Furthermore, the spacecraft will do two more fly-bys before arriving in orbit in 2026, where it will then separate into two separate orbiters in complementary orbits. Thus, this magnetic map of Mercury is merely a rough draft, and will be significantly refined by the end of the mission.

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Scientists confirm theory that thunderstorms on Earth also produce gamma ray bursts

11:42 am

Prior to the 1990s, the origin of gamma ray bursts (GRBs) was uttlerly known. First detected by satellites in the early 1970s, astronomers has no idea what caused them because without a parallel detection in optical light they had no way to determine their distance. Theories suggested the bursts could be coming from billions of light years away, from within the Milky Way, from inside the solar system, and from even the Earth’s upper atmosphere.

In the 1990s it was finally proven that GRBs almost all come from very distant cosmic events, billions of light years away, each signaling the formation of a black hole.

Now researchers have confirmed the theory that GRBs are also occuring within the Earth’s atmosphere, though these GRBs have no resemblance to the astronomical ones.

During thunderclouds, two different hard radiation phenomena have so far been known to originate: Terrestrial Gamma-ray Flashes (TGFs) and gamma-ray glows. This third phenomenon, observed and named FGFs by Østgaard et al. [2024] resembles the other two, while at the same time revealing certain characteristics separating FGFs from the others. Most noteworthy may be that FGFs are pulses of gamma-rays not associated with any detectable optical or radio signals.

“We think that FGFs could be the missing link between TGFs and gamma-ray glows, whose absence has been puzzling the atmospheric electricity community for two decades”, says lead author and Professor Nikolai Østgaard at the University of Bergen.

More information on this research can be found here. The research not only confirms the early theories as well as later detections, it adds significant nuance to the data. As noted at this second link:

“The dynamics of gamma-glowing thunderclouds starkly contradicts the former quasi-stationary picture of glows, and rather resembles that of a huge gamma-glowing boiling pot both in pattern and behavior,” said Martino Marisaldi, professor of physics and technology at the University of Bergen.

Given the size of a typical thunderstorm in the tropics, which get much larger than storms at other latitudes, this suggests that more than half of all thunderstorms in the tropics are radioactive. The researchers postulate that this low-level production of gamma radiation acts like steam boiling off a pot of water and limits how much energy can be built up inside.

This data will help refined the computer models that attempt to predict weather patterns, as it appears the phenomenon impacts the formation of thunderstorms.

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European phone companies demand the FCC stop SpaceX’s cell-to-satellite Starlink plans

10:22 am

Several European phone companies have now submitted a request to the Federal Communications Commission (FCC) to block a waiver that would allow SpaceX to operate its new cell-to-satellite Starlink satellites at radio frequencies normally not permitted.

This request follows similar requests by Verizon and AT&T to the FCC. The fear is that the use of these frequencies in the low orbit of Starlink satellites will interfere with satellites in the much higher geosynchronous orbits that these phone companies presently use.

While those concerns might be valid (SpaceX says no), these companies also fear the competition of Starlink itself, as its low orbit means it can provide better service, and are clearly hoping the FCC will act to protect them from that competition.

In a more sane world, the FCC would decide this issue on purely technical grounds. It was formed expressly to police the frequencies so that users would not interfere or pirate each others licenses, and had done that job quite well for decades.

Sadly, the FCC no longer confines itself to this one job. For the past four years the FCC has arbitrarily decided its job should include many other things not listed in its statutory authority, such as policing the de-orbiting of satellites and determining the acceptable lifespans of orbiting spacecraft, while also making many decisions based entirely on political factors, sometimes even favoring some companies over others for partisan reasons.

Thus we should have no confidence that the FCC will make this decision on purely technical grounds, especially since it has shown a clear hostility to SpaceX in its recent decisions.

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Water on the Moon? New data analysis from two different lunar orbiters say yes

10:04 am

Two papers in the past month using data from two different lunar orbiters have claimed the presence of water on Moon, based on the detection of evidence of hydrogen on the surface.

First, on September 16, 2024 scientists published a paper [pdf] that analyzed data collected in 2009 by India’s Chandrayaan-1 lunar orbiter, and concluded, as stated enthusiastically in the press release:

Map of permanently shadowed regions at the Moon's south pole
From the second paper, a map of permanently shadowed
regions at the Moon’s south pole. Click for original.

“Future astronauts may be able to find water even near the equator by exploiting these water-rich areas. Previously, it was thought that only the polar region, and in particular, the deeply shadowed craters at the poles were where water could be found in abundance,” said Roger Clark, Senior Scientist at the Planetary Science Institute and lead author of “The Global Distribution of Water and Hydroxyl on the Moon as Seen by the Moon Mineralogy Mapper (M3)” that appears in the Planetary Science Journal. “Knowing where water is located not only helps to understand lunar geologic history, but also where astronauts may find water in the future.”

Then today NASA announced the publication of a new paper [pdf] that looked at the data collected over the last decade by Lunar Reconnaissance Orbiter (LRO), and have concluded that “hydrogen-bearing volatiles are observed to be concentrated, likely in the form of water ice, within most of the Moon’s permanently shadowed regions (PSRs), poleward of 77°.” The press release, which included the map to the right of permanently shadowed areas at the Moon’s south pole, was more enthusiastic:
» Read more

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Viewing Comet Tsuchinshan-ATLAS

9:02 am

While the newly discovered Comet Tsuchinshan-ATLAS in the past week reached naked eye visibility in the dawn sky, in the next few weeks it will shift into the evening sky on October 11, 2024 while brightening to peak levels.

Although Comet Tsuchinshan-ATLAS will be visible in both hemispheres, the northern one is favored because the comet tracks north. Also, sunsets are getting earlier and twilights shorter, while the opposite is happening in southern latitudes.

Observers should be aware that the Moon will interfere for several nights, from about Oct. 15-20 (full Moon is on Oct. 17th), around the same time the comet climbs out of twilight.

As it begins to fade, the comet will be visible at an increasing height above the horizon each night through the end of October. At its brightest it is expected to be one of the brightest objects in the sky.

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October 2, 2024 Quick space links

4:26 pm

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.

 

 

 

 

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Sunspot update: Sunspot activity crashes in September

3:56 pm

As it is the start of the month, it is time another monthly sunspot update, in which I provide some context and analysis to NOAA’s most recent update of its monthly graph tracking the number of sunspots on the Sun’s Earth-facing hemisphere.

After several months in which the number of sunspots rose considerably each month, in September the sunspot count crashed, dropping precipitously to levels closer to the various predictions of solar scientists, but still far above what they had all expected at this time of the solar maximum.

» Read more

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The strange terrain of the Martian southern ice cap

12:13 pm

The strange terrain of Mars' south pole
Click for original image.

Cool image time! The picture to the right, rotated, cropped, and sharpened to post here, was taken on July 29, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a section at the Martian south pole at the very high latitude of 87 degrees south, only about 100 miles from the pole itself.

The label for this picture is “possible water ice and mesas,” suggesting we are looking at an ice cap of water that is partly sublimated away.

In truth, things are much more complicated. It was summer when this photo was taken. Note the drainage in the lower right and the dark spidery lines there. In the winter on Mars atmospheric carbon dioxide falls as snow and coats the poles to about 60 degrees latitude with a thin mantle of dry ice. In the spring this mantle sublimates away, but does so in an counter-intuitive manner. The sublimation first occurs at the mantle’s base, and the trapped gas flows up until it finds a weak spot in the mantle and cracks through, spewing out and deposting dark splotches of dust.

At the south pole this upward flow always follows the same paths, producing the dark spidery patterns we see here. In the case of the drainage in the lower right, this is a drainage of gas eastward until it pops out at the slope, causing that depression to become darkly stained.

This is only part of the story of this complex geology, however.
» Read more

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Mid-October date for the 5th Starship/Superheavy test orbital launch?

10:01 am

A US Coast Guard announcement issued today includes a notice to mariners of a rocket launch window at Boca Chica from October 12th to October 19th, suggesting that SpaceX has gotten an update from the FAA that a launch license will be issued for those dates, more than a month earlier than previously predicted by the FAA.

It must be emphasized that this notice is from the Coast Guard, not the FAA. The FAA has said nothing new about SpaceX’s launch license application. This notice suggests several possiblilites, all or none of which may be true:

1. The FAA has told SpaceX privately that it expects to issue that license in time for a launch in two weeks, and SpaceX then moved quickly to get the Coast Guard in line.

2. SpaceX and the Coast Guard are working together to increase the pressure on the FAA to get out of the way.

3. The public condemnations of the FAA by SpaceX in the past few weeks have worked to force that agency to back off its hardnosed regulatory over-reach.

All of this is wild speculation. For all we know, this Coast Guard notice is something it always issues prior to major static fire tests at Boca Chica. We shall have to wait to get a better sense of what is happening.

Hat tip to reader Steve Richter.

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Scientists detect jets of carbon dioxide and carbon monoxide from asteroid

9:45 am

Jets from asteroid
Click for original graphic.

Using the spectroscopy from the Webb Space Telescope, scientists have now detected jets of carbon dioxide and carbon monoxide spewing from the very active asteroid 29P/Schwassmann-Wachmann-1 (29P).

Based on the data gathered by Webb, the team created a 3D model of the jets to understand their orientation and origin. They found through their modeling efforts that the jets were emitted from different regions on the centaur’s nucleus, even though the nucleus itself cannot be resolved by Webb. The jets’ angles suggest the possibility that the nucleus may be an aggregate of distinct objects with different compositions; however, other scenarios can’t yet be excluded.

The graphic to the right illustrates the modeling of these jets. That the center of this two-lobed asteroid could have been created from distinct objects suggests a very complex formation process, since those objects would have had to have formed themselves in different locations in the solar system and then somehow come together.

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ESA awards Polish rocket startup €2.4 million contract

9:33 am

The European Space Agency (ESA) has awarded a Polish rocket startup, dubbed SpaceForest, €2.4 million to upgrade its suborbital Perun rocket that the company has test launched twice in last year.

Perun runs on modified paraffin, commonly used as candle wax, and so its propellant is non-toxic. The rocket can be launched on a mobile launch pad, allowing for easy deployment at launch facilities around Europe. Last year, SpaceForest launched two full-scale models of its Perun rocket that flew to 22 km and 13 km altitude from the coastal town of Ustka, Poland, on the Baltic Sea.

This company is now the second Polish rocket startup to have successfully tested its rocket. The Łukasiewicz Institute of Aviation has completed suborbital test flights of its ILR-33 Amber 2K rocket, and has a deal to fly its next test from Norway’s commercial Andoya spaceport.

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ISRO reveals design of its Chandrayaan-4 lunar sample return mission

9:23 am

India’s space agency ISRO yesterday unveiled its design concept for its Chandrayaan-4 lunar sample return mission, requiring two launches and five modules that will dock in Earth orbit before traveling to the Moon.

“After two launches, the stacks will be docked together in elliptical Earth orbit to form an integrated stack. Subsequent to docking, the Integrated Stack will perform the first set of Earth-bound manoeuvres with the PM propulsion system. Once the PM is depleted, it gets jettisoned from the Integrated stack,” Isro said Tuesday.

The integrated stack then performs all the manoeuvres to achieve the lunar orbit, such that the orbit plane has the pre-determined landing site. In the final lunar orbit, the descender module and ascender module get separated from the transfer module and re-entry module. The descender and ascender modules then undergo powered descent to achieve a soft landing on the lunar surface.

Both a robot arm and a drill will then grab samples, deposit them separately in the ascender, which will then launch and redock with the stack. It will then take the re-entry module back toward Earth, where it will be released prior to its return.

This plan is essentially the same as the first proposal last year, but with many more added details.

A landing site has apparently not yet been chosen.

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Orbital tug startup Impulse Space raises $150 million

9:12 am

The orbital tug startup Impulse Space announced yesterday that it has raised $150 million in private investment capital, money it will use to develop its planned two tugs, dubbed Mira and Helios.

So far the company, founded by former SpaceX engineer Tom Mueller, has only flown one mission, a demo mission of Mira last year that had some communications and software problems but was still declared a success.

Both Mira and Helios use chemical propulsion systems that offer large amounts of delta-v, or change in velocity, that can be provided quickly. Impulse said when it announced Helios that the vehicle could take a five-ton satellite from low Earth orbit to geostationary orbit in less than a day.

It hopes to fly an upgraded version of Mira late next year, and the first Helios mission in 2026.

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Carbon dioxide and hydrogen peroxide found on the surface of Pluto’s moon Charon

9:03 am

Using spectroscopic data from the Webb Space Telescope, scientists have detected both carbon dioxide and hydrogen peroxide on the surface of Pluto’s moon Charon, adding these chemicals to the previously detected water ice and ammonia-bearing chemicals that give the planet its gray and red colors.

The team compared the spectroscopic observations with laboratory measurements and detailed spectral models of the surface, concluding that carbon dioxide is present primarily as a surface veneer on a water ice-rich subsurface. “Our preferred interpretation is that the upper layer of carbon dioxide originates from the interior and has been exposed to the surface through cratering events. Carbon dioxide is known to be present in regions of the protoplanetary disk from which the Pluto system formed,” Protopapa said.

The presence of hydrogen peroxide on the surface of Charon clearly indicates that the water ice-rich surface is altered by solar ultraviolet light and energetic particles from the solar wind and galactic cosmic rays. Hydrogen peroxide forms from oxygen and hydrogen atoms originating from the breakup of water ice due to incoming ions, electrons or photons.

The theory proposing the dry ice comes from the interior is interesting, but there simply is not enough data to take it very seriously at this point.

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Russia delays first launch of new Soyuz-5 rocket to 2026

8:52 am

According to Russia’s state-run press, the first launch of its new Soyuz-5 rocket will not occur in 2025 as previously predicted, but has been delayed to 2026.

No reason for the delay was given, but I suspect it is because Russia has still been unable to negotiate a deal with Kazakhstan for the use of the planned launchpad at Baikonur. In 2023 Kazakhstan seized control of the Soyuz-5 launchpad, and has apparently so far refused to agree to a new deal for allowing Russia to use it.

These negotiating delays with Kazakhstan are not the Soyuz-5 rocket’s only issues. Russia first announced the rocket in 2015, with its first launch planned for 2022. Thus, long before Kazakhstan retook its launchpad in 2023 the project was behind schedule. Other plans in 2019 to launch it from the former commercial Sea Launch platform that Russia took over have come to nothing.

Kazakhstan’s unwillingness to negotiate almost certainly stems from Russia’s invasion of the Ukraine. It now fears Russia, and is very reluctant to give it more control of Kazakhstan’s assets.

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Engineers shut down one science instrument on Voyager-2 to conserve power

8:38 am

In order to keep the spacecraft functioning as its nuclear power source dwindles, engineers have now shut down one of Voyager-2’s operating science instruments in order to keep four instruments operating.

Mission engineers at NASA have turned off the plasma science instrument aboard the Voyager 2 spacecraft due to the probe’s gradually shrinking electrical power supply.

Traveling more than 12.8 billion miles (20.5 billion kilometers) from Earth, the spacecraft continues to use four science instruments to study the region outside our heliosphere, the protective bubble of particles and magnetic fields created by the Sun. The probe has enough power to continue exploring this region with at least one operational science instrument into the 2030s. [emphasis mine]

The highlighted sentence is the first time I have ever seen any prediction for the life of Voyager-2 to extend past 2030. Previously, project engineers have consistently stated that the power would run down sometime around 2026. This extension suggests the decision has been made to do whatever can be done to keep the spacecraft functioning for as long as possible, not so much to do science but to test the limits of its engineering. To do so, they will step-by-step shut down instruments rather than keep them all going.

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October 1, 2024 Quick space links

3:29 pm

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.

 

 

9 comments

Busy cooking

3:20 pm

I have not posted this afternoon because I am cooking my quarterly batch of tomato meat sauce, as per my mother’s recipe that was handed to her from our Italian-Jewish relatives. Time consuming, but I get enough frozen to last for at least three months.

One of my readers requested I share the recipe, so here it is. The quantites below are for making a large batch, 9 meals for two (splitting a meatball), and an additional uncounted number of pasta dishes (meat ravioli, spaghetti, rigatoni, etc). Usually lasts Diane and I about three months.

Ma Zimmerman’s spaghetti sauce
» Read more

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Astronomers detect exoplanet half as massive as the Earth around second closest star system

11:28 am

Using the Very Large Telescope (VLT) in Chile, astronomers have detected evidence of an exoplanet about half as massive as the Earth orbiting Barnard’s Star, only six light years away and the second closest star system.

Barnard’s Star is a prime target in the search for exoplanets due to its proximity and its status as a red dwarf, a common type of star where low-mass planets are often found. Despite a promising signal detected in 2018, no planet had been definitively confirmed around it until now. The ESPRESSO spectrograph [on VLT] … enabled the astronomers to detect Barnard b, a subterrestrial planet that orbits the star in 3.15 days. The team also identified signals indicating the possible presence of three other candidate exoplanets, which have yet to be confirmed.

Back in the 1960s using the less precise instruments of the time, astronomers thought they had detected an exoplanet orbiting Barnard’s Star. That detection however proved false. The detection is real, however, and adds weight to the growing evidence that planets can form around red dwarf stars, the most common stars in the universe with the longest lifespan, predicted to be many tens of billions of years. Having planets around such stars significantly increases the chances of habitable planets, even if those planets do not harbor life of its own.

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Gogo buys competitor Satcom Direct

9:53 am

Gogo, which provides internet access for business jets, has now purchased its main competitor Satcom Direct, in order to provide a service that can better compete with Starlink.

Satcom Direct would get $375 million in cash and five million shares from Gogo under a deal announced Sept. 30, subject to regulatory approvals, and up to $225 million in extra payments tied to performance targets over the next four years, suggesting around $636 million in maximum total proceeds.

Gogo has historically dominated the small and midsize part of the business aviation market and connects about 7,000 planes, according to William Blair analyst Louie DiPalma, while Satcom Direct has a commanding market share for long-haul.

Combined, William Blair estimates the companies are providing Wi-Fi to around 8,200 of the 9,200 business jets that currently have connectivity — or nearly 90% of the market.

Gogo’s share price has dropped 70% since 2022 in the face of Starlink’s recent signing of numerous airline companies. The stock market obviously thinks Starlink is eventually going to capture the business jet customer as well. This deal will possibly allow Gogo to compete more effectively.

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Data from two different studies suggest Betelgeuse has a Sun-sized companion star

9:46 am

Betelqeuse
An optical image of Betelgeuse taken in 2017 by a ground-based
telescope, showing its not unusual aspherical shape.
Click for original image.

Two different independent studies have uncovered evidence that the red giant star Betalgeuse likely has an unseen companion star about the mass of the Sun and orbiting it every six years.

MacLeod and colleagues linked a six-year cycle of Betelgeuse brightening and dimming to a companion star tweaking its orbit, in a paper submitted to arXiv.org September 17. MacLeod examined global, historical measurements dating back to 1896.

Separately, Jared Goldberg of the Flatiron Institute in New York and colleagues used the last 20-odd years of measurements of Betelgeuse’s motion on the sky, which have the highest precision. That team also found evidence of a companion nudging the bigger star, submitted to arXiv.org August 17.

Previous observers noticed Betelgeuse’s light varying on a roughly six-year cycle. In 1908, English astronomer Henry Cozier Plummer suggested the cycle could be from the gravity of a companion star tugging Betelgeuse back and forth.

You can download the two papers here and here. This quote from the first paper’s abstract not only explains why the star has not been detected previously, but suggests its doomed future:

The companion star would be nearly twenty times less massive and a million times fainter than Betelgeuse, with similar effective temperature, effectively hiding it in plain sight near one of the best-studied stars in the night sky. The astrometric data favor an edge-on binary with orbital plane aligned with Betelgeuse’s measured spin axis. Tidal spin-orbit interaction drains angular momentum from the orbit and spins up Betelgeuse, explaining the spin–orbit alignment and Betelgeuse’s anomalously rapid spin. In the future, the orbit will decay until the companion is swallowed by Betelgeuse in the next 10,000 years. [emphasis mine]

The presence and future capture of this small companion star will help astronomers better calculate future fluctuations of Betelgesue itself. That capture is also going to occur relatively soon, on astronomical time scales.

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