Category: Behind The Black

Blue Ghost instrument proves Earth-orbiting GPS-type satellites can be used to track location from the Moon

9:16 pm

Having now reached lunar orbit in preparation for its landing on March 2, 2025, an engineering test instrument on Firefly’s Blue Ghost lunar lander has now proven that even from that distance spacecraft can use the multiple GPS-type satellites in Earth orbit to track their position.

The Lunar GNSS Receiver Experiment (LuGRE) acquired and tracked Global Navigation Satellite System (GNSS) signals for the first time in lunar orbit – a new record! This achievement, peaking at 246,000 miles, suggests that Earth-based GNSS constellations can be used for navigation in transit to, around, and potentially on the Moon. It also demonstrates the power of using multiple GNSS constellations together, such as GPS and Galileo, to perform navigation. After lunar landing, LuGRE will operate for 14 days and attempt to break another record – first reception of GNSS signals on the lunar surface.

This test is a very big deal. It tells us that operations on the Moon, at least those on the near side, will likely not require a GPS-type infrastructure in lunar orbit, thus allowing a lot of difficult missions to proceed sooner while saving a lot of money and time.

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China and SpaceX complete launches

7:36 pm

Two more launches today. First China launched a communications satellite into orbit, its Long March 3B rocket lifting off from its Xichang spaceport in the southwest of China. No word on where the rocket’s core stage and four side boosters crashed inside China. Nor has China released much information about the satellite itself.

Next SpaceX placed another 22 Starlink satellites, its Falcon 9 rocket lifting off from Vandenberg in California. The first stage completed its eleventh flight, landing on a drone ship in the Pacific.

The leaders in the 2025 launch race:

23 SpaceX
8 China
2 Rocket Lab

At this moment SpaceX’s 23 launches in 2025 is not far short of being twice as much as the 14 launches completed by rest of the entire world combined. It certainly is outpacing everyone else quite handily.

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Alison Balsom – Introducing the Baroque Trumpet

6:01 pm

An evening pause: Another music history lesson to start the weekend. As she says, listening to baroque music played on this instrument explains a great deal about that music, and definitely tells you what that music was expected to sound like when composed, compared to playing it on modern instruments. Far more haunting, a word I would never have used to describe Baroque music before.

Hat tip Judd Clark.

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February 21, 2025 Quick space links

4:39 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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A Martian glacier of dust

3:14 pm

A Martian glacier of dust
Click for original image.

Cool image time! The picture above, rotated, reduced, and sharpened to post here, was taken on September 2, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The tiny white dot near the lower center of the overview map below marks the location, on the northern wall of the smaller parallel canyon to the much larger part of Valles Marineris dubbed Coprates Canyon.

The scientists label this a “slope deposit.” What I see is a dust glacier flowing down hill in that long hollow (indicated by the arrows), with the ripple dunes actually acting almost like waves. Nor is this description unreasonable. On Mars the dust will gather in the hollows of these slopes and over time, with no rain and little wind to disturb them, will begin to flow down much like a glacier.

In this case, the descent is gigantic, considering the size of Valles Marineris. From the top to bottom of this image the elevation drop is about 14,000 feet over a distance of 11 miles.

Overview map

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Musk: ISS should be de-orbited quickly! And he may be right.

12:23 pm

Figure 3 from September Inspector General report
Figure 3 from September Inspector General report, showing ISS and outlining the airlieak annotated to show Zvezda and Poisk locations.

Food fight! Yesterday Elon Musk did a Donald Trump, issuing a bunch of tweets that are likely causing some heads to explode inside NASA, Congress, and Europe.

First — and far less significant — Musk got into a war of insults with European Space Agency astronaut Andreas Mogensen over his comments in recent days accusing the Biden administration of delaying the return of the two Starliner astronauts “for political reasons.” Mogensen accused Musk lying about this, and Musk responded by calling Mogenson “fully retarded” and an “idiot,” adding that “SpaceX could have brought them back several months ago. I OFFERED THIS DIRECTLY to the Biden administration and they refused. Return WAS pushed back for political reasons.”

Since Musk was there and Mogensen was not, it seems Musk won that battle. NASA meanwhile issued a mild statement saying everything it has done has been to maximize safety, a statement that matches the facts quite accurately.

Then Musk — on a far more important topic — stirred the pot more by tweeting his belief that ISS should be retired now.

It is time to begin preparations for deorbiting the Space_Station. It has served its purpose. There is very little incremental utility. Let’s go to Mars.

In a second tweet he recommended the de-orbit should occur “two years from now.”

Left unstated by Musk was what might be his most important reason for retiring ISS so quickly: the fragile condition of the Russian-built Zvezda module. » Read more

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Airbus writes off $314 million for unnamed space program losses

10:45 am

Airbus on February 20, 2025 announced that it has written off $314 million due to issues in an unnamed program in its space division, adding to an almost billion dollar write-off in June 2024.

Airbus said Feb. 20 it took the 300-million-euro charge in the fourth quarter of 2024 as it completed reviews of a final, unnamed program in its space portfolio. The company had hinted in late October that it could take additional charges on that program as it completed a comprehensive review. “We had to go through the program in detail, bottom up, to fully review what we had in our portfolio, and that we have done,” Thomas Toepfer, chief financial officer of Airbus, said in a call with analysts. He did not identify that program.

The company took 900 million euros in charges in June 2024, and the company said the total charges against earnings on its space business in 2024 was 1.3 billion euros. Toepfer said that the company does not anticipate additional charges as it’s completed the review of all its space programs.

There are some hints that the program involved bad bids for satellite contracts and with suppliers. I can’t help wondering if it is also related to the overall failure of Ariane-6 to garner customers. Airbus builds and owns it in partnership with Safran.

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Billionaire who fought Sutherland spaceport now owns at least half of competing Saxavord spaceport

9:46 am

Proposed spaceports surrounding Norwegian Sea
Proposed spaceports surrounding Norwegian Sea

Anders Povlsen, the Danish billionaire who aggressively fought the establishment of the Sutherland spaceport on the north coast of Scotland, where he owns lots of land, has increased his holding of the competing Saxavord spaceport on one of the Shetland Islands, raising his share of ownership there to at least 50%.

Danish billionaire Anders Povlsen has increased his stake in Shetland Space Centre via his company, Wild Ventures Ltd, which now owns more than half of its shares. New filings with Companies House also show that Lise Kaae, the chief executive of Mr Povlsen’s investment firm, Heartland, has been appointed as a director at the spaceport.

Mr Povlsen, who made his fortune in retail fashion and is reported to be Scotland’s largest landowner, has been involved in the spaceport since 2020 when Wild Ventures Ltd invested £1.5m.

Povlsen had for years aggressively opposed Sutherland, expressing that opposition with repeated lawsuits that caused years of regulatory delays. Those delays in turn impacted Sutherland’s biggest customer, the rocket startup Orbex, which had a fifty year lease on a launchpad and had hoped to start launches of its Prime rocket in 2022. In December 2024, with no sign it would get a launch license from the UK’s Civil Aviation Authority anytime soon, Orbex essentially gave up on Sutherland, announcing suddenly it was switching launch operations to Saxaford.

It now appears Povlsen’s lawfare effort has born fruit, which I think explains why he has now suddenly increased his ownership share in Saxavord

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New observations reduce odds of asteroid 2024 YR4’s 2032 Earth impact to practically zero

9:26 am

The uncertainty of science: According to a short update from NASA late yesterday, new ground-based observations have now reduced the odds that asteroid 2024 YR4’s will hit the Earth in 2032 to only 0.28 percent.

Observations made overnight on Feb. 19 – 20 of asteroid 2024 YR4 have further decreased its chance of Earth impact on Dec. 22, 2032, to 0.28%. NASA’s planetary defense teams will continue to monitor the asteroid to improve our predictions of the asteroid’s trajectory. With this new data, the chance of an impact with the Moon increased slightly to 1%.

Expect these numbers to change again in March, when the Webb telescope tracks the asteroid. And do not assume Webb will confirm these numbers. There remains great uncertainty in all these calculations, especially because there is great uncertainty about the size, mass, and make-up of 2024 YR4. It could be anywhere from 130 feet to 320 feet in diameter, and that difference makes these calculations uncertain.

In other words, it remains essential that work should begin on putting together a mission to visit and study this asteroid, now. Though it isn’t large enough to cause a worldwide extinction, it is big enough to do very significant damage, depending on where it hits.

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Justice Department drops absurd Biden-era discrimination lawsuit against SpaceX

9:15 am

As expected, the Justice Department now under Donald Trump’s presidency yesterday filed papers to end the insane Biden-era discrimination lawsuit against SpaceX that demanded it hire refugees and even illegal aliens, even though State Department rules forbid it to do so.

In an unopposed motion filed with the U.S. District Court for the Southern District of Texas, the Justice Department said it intended to file a notice of dismissal with prejudice, which means prosecutors would not be able to file these charges again.

Of all the lawfare initiated against Musk and SpaceX by the Biden administration, this lawsuit was by far the stupidest and most ridiculous. SpaceX doesn’t discriminate against non-American citizens. If they meet State Department rules and also have the qualifications, it hires them. And has done so. For one federal agency, Justice, to demand that SpaceX violate the rules of another agency, State, proves the lawsuit’s real purpose was harassment only.

That harassment has ended with the arrival of Trump.

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German rocket startup Isar Aerospace completes ground testing of Spectrum rocket

9:07 am

Proposed spaceports surrounding Norwegian Sea
Proposed spaceports surrounding Norwegian Sea

The German rocket startup Isar Aerospace today announced that it has completed its static fire engine test program for both stages of its new Spectrum rocket, and is now readying that rocket for its first orbital launch “as soon as possible”.

Satellite launch service company Isar Aerospace is preparing for its first test flight, having successfully completed static firings of both stages of its launch vehicle ‘Spectrum’. The first flight will take place from Andøya Spaceport in Norway as soon as possible following Norwegian Civil Aviation Authority (NCAA) approval and licensing.

Based on how fast Norway’s bureaucracy has moved so far, that licensing process should not take that long. Expect this first launch to take place within months, even weeks. If so, Isar will have won the race to reach orbit among the half-dozen or so new European rocket startups that have popped up in the past three years, while Norway’s Andoya Spaceport will have won the race to initiate orbital spaceport operations, beating out the spaceports in the United Kingdom and Sweden.

Isar also notes that its next two rockets are already in production, which means it wants its orbital test program to move quickly to operational commercial flights.

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Spanish rocket startup PLD signs deal for a second launch site at Oman’s proposed spaceport

3:36 pm

Middle East, showing Oman's proposed spaceport
The Middle East, showing the location of
Oman’s proposed spaceport at Duqm.

The new colonial movement: The Spanish rocket startup PLD announced today that it has signed an agreement with Oman to use that nation’s proposed spaceport at Duqm for future launches.

From its strategic location in Duqm (Oman), we address the proximity flight needs of our clients, especially in the Middle East.

With our Launch Complex at the European CSG spaceport (Kourou, French Guiana), we cover the Western market, and now with Etlaq, we’re covering the Eastern one too. This strengthens our position as global pioneers.

The company also said in 2026 it plans to add a third launch site. BtB’s stringer Jay, who sent me this story, thinks it will be in the Pacific somewhere.

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February 20, 2025 Quick space links

3:30 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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Ghouls and Monsters in Gaza

12:22 pm

Hamas in all its monstrous glory

Word fail. For any decent human being, the behavior of the Hamas killers today in releasing the four bodies of their kidnapped hostages — which included a baby and a toddler — was beyond monstrous.

The picture to the right gives only a sense. The coffins were put on display on a stage, with celebratory music blaring. The poster in the background shows the faces of the four dead hostages, including a 9-month-old and a four-year-old, with a vampire-version of Bibi Netanyahu dripping blood on them. A large crowd of several thousand was there to watch, with many cheering. The coffins were then carried one by one to Red Cross vehicles while that crowd cheered and the music blasted. Even UN officials were offended, noting that the parading of bodies violates international law.

The coffins themselves were locked, and Hamas provided no keys. Before they can be pried open so that the bodies can be properly buried, Israeli technical experts have to first determine if the coffins are booby-trapped. (Sounds insane, but would you nonchalantly pry open one of these Hamas-sealed coffins?)

Hamas tried to put the blame on the death of these four innocents by claiming they were killed by an Israeli bombing attack. That however is utterly irrelevant, even if it was true. These four human beings were ripped from their homes on October 7, 2023 by Hamas/Gaza savages and imprisoned in the hellhole tunnels of Gaza, merely because they were Jews. Hamas is entirely at fault.

UPDATE: Forensic evidence has now shown that the baby and toddler were actually murdered about one month after their kidnapping while in captivity, and the woman’s body was not of their mother, Shiri Biba, but of an anonymous unidentified body. In other words, Hamas dug up a body of some unknown person and gave that back to Israel. At this moment we have no idea if Shiri Biba is alive or dead, though she is most likely dead but Hamas did not want to release the body probably because it would have revealed more evidence of their savagery. I suspect they raped and tortured her before killing her.

Worse, Hamas is proud of what it has done. At no point has the leadership of Hamas ever backed off from its goal of killing all Jews, worldwide, and then all Christians, in order to establish a worldwide caliphate of Islam.

As Islamic scholar Robert Spencer noted in documenting this horror show,
» Read more

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French startup The Exploration Company wins major contract from Germany

9:39 am

Germany’s space agency, DLR, announced today that it has signed a major contract with the French startup The Exploration Company to use its Nyx reusable capsule, still under development, for in-orbit weightlessness research.

On 20 February, during its DLR TecDays in Bonn, the German aerospace agency announced that it had signed a contract with The Exploration Company and would serve as an anchor customer for its microgravity research service. The contract secures space for 160 kilograms of scientific payloads aboard the inaugural flight of the Nyx Earth capsule in 2028. “We are supporting a startup that provides services that will be particularly valuable in a post-ISS era,” explained Dr. Walther Pelzer, Head of the German Space Agency at DLR.

Nyx’s main customer base was originally to serve as a cargo freighter for all of planned commercial space stations, having already been chosen by the European Space Agency as one of two European companies (the other being Thales-Alenia) to fly cargo demonstration missions to ISS in 2028.

This new contract illustrates the wider possibilities for profit for these capsules that has appeared in the past two years. If you can launch a returnable capsule to bring cargo, why not launch it to do in-orbit research and manufacturing? Varda in the U.S. has already demonstrated this possibility. Others apparently are now recognizing it as well.

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The man who has been running NASA’s manned Artemis program resigns

9:31 am

Late yesterday NASA officially announced that Jim Free, who has been running NASA’s manned Artemis program for the past year, has decided to resign.

Only a month or so ago the people at NASA had assumed that Free would take over as the agency’s acting administrator during the transition from Bill Nelson, appointed by Biden, and Jared Isaacman, appointed by Trump. Instead, Trump’s transition team gave this job to Janet Petro, who had been head of the Kennedy Space Center in Florida. Free has been seen as a headquarters guy who has for years favored the old big space companies like Boeing and who also has favored SLS and Orion and the old way of doing things, whereby NASA designs, builds, and controls everything instead of simply buying what it needs from the private sector.

There have also been reports that “three key officials” at the Marshall Space Flight Center in Alabama have also submitted their retirement papers. This would suggest that the earlier proposals by Trump’s NASA transition team to shrink or eliminate many of NASA’s numerous centers scattered across the country are being seriously discussed, and possibly being implemented.

Many news sources have concluded that the decision by the Trump administration to delay its major layoffs at NASA was because the Trump administration was reconsidering these major changes. I disagree. I think it is holding off because the new administrator has not yet been confirmed by the Senate, and it decided he should have a say in these reductions and changes. The retirement and resignation of these old school NASA management types further tells us that major changes are coming.

Overall, my guess is that a major reorganization of NASA — including the elimination of many of its centers — could reduce its overhead by $5 to $10 billion per year. Part of those savings could be used to reduce the deficit, but some could also be used to increase the amount of money available for all of NASA’s goals. I made this point fourteen years ago, and nothing has changed since then except that NASA has wasted billions over that time accomplishing nothing with SLS and Orion.

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Boeing announces a new round of layoffs related to its SLS NASA contract

9:02 am

Boeing yesterday announced that it will layoff another 71 employees in connection with its SLS NASA contract, based on rumored changes in NASA’s entire Artemis lunar program, including the increasingly real possibility that SLS will be canceled entirely by the new Trump administration.

The defense contractor was already in the midst of reducing its workforce, including in Alabama. But today, the company told AL.com that changes to its contract with NASA to develop the Space Launch System program sparked the need for some of the 71 layoffs. “As Boeing and NASA continue to finalize contract revisions for Boeing’s work on the Space Launch System program, we have successfully mitigated a majority of the previously announced workforce reductions,” a Boeing spokesperson said in an email to AL.com.

The news article at the link actually suggests that the total number of layoffs is now half that predicted by the company a few weeks ago, so it remains very unclear if these layoffs are because NASA is considering cancelling SLS, or because Boeing is simply shifting SLS management from development (which requires more people) to routine operations.

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The uncertainty of science: Astronomers keep changing the odds of asteroid 2024 YR4 hitting the Earth in 2032

8:53 am

In the past three days three different reports from both NASA and the European Space Agency have given three different percentages for the chances that asteroid 2024 YR4 will hit the Earth in 2032.

On Tuesday, NASA calculated that the space rock had a 3.1% chance of hitting Earth in 2032, while the European Space Agency’s risk assessment sits at 2.8%.

The narrow difference is due to the two agencies’ use of different tools for determining the asteroid’s orbit and modeling its potential impact. But both percentages rise above the 2.7% chance of collision once associated with an asteroid discovered in 2004 called Apophis, making 2024 YR4 the most significant space rock to be spotted within the past two decades.

However, another update shared by NASA on Wednesday showed that 2024 YR4 has a 1.5% chance of colliding with Earth in December 2032, based on new observations now that the full moon has passed. Astronomers have anticipated that such fluctuations are possible as they gather more observational data.

While the media has generally focused mostly on the higher numbers in their knee-jerk “We’re all gonna die” approach to everything, all these different numbers simply illustrate is the generally limited nature of our data about the asteroid’s orbit and its future path. For example because such asteroids are so small, it isn’t just gravity that influences their flight path through the solar system. The Sun’s light pressure can actually have an impact, but to determine how much you need to know the exact size, shape, and rotation of the object. Right now 2024 YR4’s size is estimated to range from 130 to 320 feet in width, determining this effect is presently impossible. Nor is this the only such variable.

At the same time, the data continues to suggest that the chances of this asteroid hitting the Earth are not trivial. The sooner we can find out everything about it the better. Getting a mission to it quickly would be the best way, but so far I have heard little from NASA or anyone about such an idea.

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February 19, 2025 Quick space links

3:51 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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Australian rocket startup Gilmour Space appears to have finally gotten its launch license

3:29 pm

Australian commercial spaceports
Australia’s commercial spaceports. Click for original map.

According to two news reports (here and here) as well as an update today on the company’s website, the Australian rocket startup Gilmour Space has gotten its last government approval allowing it to finally do the first orbital test launch of its Eris rocket from its private Bowen launch site on the east coast of Australia.

Though the company has not yet announced a launch date, the news reports and previous announcements suggest it will occur in late March. This document [pdf] provides excellent details about the launch, including the range limitations and flight path. No live stream will be provided on this first launch attempt.

I expect more information to be announced either later today or tomorrow. If this is confirmed, it will have been a long time coming. Gilmour first applied for its launch license in April 2022, with the intention of launching that year. Unfortunately, Australia’s Civil Aviation Safety Authority (CASA) appears as slow and as difficult to work with as the United Kingdom’s Civil Aviation Authority. It took CASA almost three years to issue this license (assuming it has been issued). With that kind of red tape, I don’t know how Gilmour is going to become profitable. It certainly can’t wait three years between each launch.

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The broken edge of Mars’ largest volcanic ash field

12:54 pm

The broken edge of Mars' largest volcanic ash field
Click for original image.

Overview map

Cool image time! The picture above, reduced and rotated to place north to the left, was taken on November 5, 2024 by the high resolution camera on Mars Reconnaissance Orbiter (MRO).

The science team labeled it “Stepped Features in Tartarus Skopulus”. The white dot on the overview map to the right marks the location, right at the equator on the northern edge of the Medusae Fossae Formation, the largest volcanic ash field on Mars, about the size of the subcontinent of India. As I wrote in a post in 2024:

It is believed that most of the planet’s dust comes from this ash field. It is also evident that the ash is a leftover from the time period more than a billion years ago when the giant volcanoes that surround this field were erupting regularly. The eruptions laid down vast flood lava plains that coat the surface for thousands of miles.

The ash either came from the eruptions themselves, or was created as the thin Martian wind eroded those flood lava plains, slowly stripping ash from the top. The ash then gathered within the black-outlined regions on the map.

In that 2024 post the cool image showed another location on the north edge of Medusae. In that case the prevailing wind had carved long parallel ridges as it pulled ash from the field.

Here, the wind appears to play no part, or if it did, it produced a very different terrain. At first glance it appears the stepped terraces formed as the ash field began to slide downhill to the north, spreading to crack along the curved lines. The inset especially suggests this explanation.

A closer look instead suggests these terraces each represent a different layer of ash placed down by a sequence of eruptions. Over time the prevailing winds, which here appear to generally blow to the south, stripped off the top of each layer, creating this stair-step landscape.

I however have no guess as to why the terraces are curved. Regardless, it is all strange, but quite beautiful in its own way.

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Alaskan spaceport sues insurance company over delayed rocket clean-up claims

11:06 am

The Alaskan spaceport in Kodiak has now sued the insurance company of the rocket startup ABL (now out of the orbital rocket business) because it has not responded to the spaceport’s claims for cleaning up the mess caused by a failed static fire engine test.

According to the spaceport, the cost of the damages and cleanup totals about $3.1 million.

The corporation claims ABL Space Systems was required to carry insurance that covered the spaceport, and had a policy for up to $50 million through the U.S. Aircraft Insurance Group (USAIG) to cover the damages.

But after sending three emails to USAIG asking for a copy of its policy and status on a filed claim, which allegedly existed but was never confirmed by the insurance group, Alaska Aerospace’s lawyer Cook with Birch Horton Bittner & Cherot sent a final follow up email last month on Jan. 8.

Having still not gotten a response, the spaceport has now sued. Delays and suits like this are not unusual in the insurance business, because insurance companies often stall when it comes to paying out large claims.

The failure during the static fire test was the final blow in ABL’s effort to enter the orbital launch market. After one failed launch and this static fire test failure it abandoned the market to instead focus on building missiles for the military.

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Musk: Biden delayed the return of Starliner’s astronauts “for political reasons”

10:06 am

During a television interview with President Trump, Elon Musk suggested that the reason the two Starliner astronauts have been forced to remain on ISS for months was because of a political decision by the Biden administration last year.

The billionaire SpaceX CEO said his company was “accelerating the return of the astronauts” as per Trump’s instructions. Musk then appeared to take a shot at the Biden administration, saying the move was “postponed kind of to a ridiculous degree,” before the president chimed in saying “they got left in space.”

When Hannity pointed out the astronauts have been on the ISS for almost 300 days instead of the planned 8 days, Trump simply said “Biden,” before Musk claimed they were “left up there for political reasons, which is not good.”

While the decision to return Starliner unmanned certainly had a political component (a desire to avoid a disaster in the final year of Biden’s term), Musk’s claim is greatly exaggerated. Worse, Musk is papering over his own company’s contribution to the delays. Had SpaceX and NASA chosen in December to use an already existing Dragon capsule instead of a brand new capsule to launch the next crew to ISS, the astronauts would be home already. Instead, they decided to get that new capsule ready, requiring an almost two month delay in their return.

When it became obvious last month that even this extra time was insufficient to get the new capsule ready, only then did SpaceX and NASA choose to switch capsules. That switch allowed them to move up the return date by about a week.

In reporting Musk’s words here, our ignorant press has generally left these details out, allowing both Musk and Trump to make it appear as they are saviors for these poor astronauts. This is simply not true. SpaceX is certainly making it possible to bring them home (something Boeing was unable to do), but it also contributed to the delay in doing so.

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New data from Webb shows the Milky Way’s central supermassive black hole flares multiple times per day

9:47 am

The magnetic field lines surrounding Sagittarius A*
The magnetic field lines surrounding Sagittarius A*,
published in March 2024. Click for original image.

Though past research had shown that the Milky Way’s central supermassive black hole, dubbed Sagittarius A* (pronounced A-star) is generally quiet and inactive, new data from the Webb Space Telescope gathered over a year’s time now shows that it flares multiple times per day.

Throughout the year, the team saw how the black hole’s accretion disk emitted 5 to 6 large flares per day, of varying lengths and brightnesses, plus smaller flares in between. “[Sagittarius A*] is always bubbling with activity and never seems to reach a steady state,” Yusef-Zadeh says. “We observed the black hole multiple times throughout 2023 and 2024, and we noticed changes in every observation. We saw something different each time, which is really remarkable. Nothing ever stayed the same.”

In their paper published in The Astrophysical Journal Letters, the team outlines two possible ideas for the processes driving these flares. The faint flickers may be caused by turbulent fluctuations in the accretion disk, which could compress plasma and trigger a burst of radiation. “It’s similar to how the sun’s magnetic field gathers together, compresses and then erupts a solar flare,” Yusef-Zadeh says. “Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme.”

The larger and brighter flares, on the other hand, may be caused by two fast-moving magnetic fields colliding and releasing accelerated particles. These magnetic reconnection events also have a solar parallel.

You can read their paper here [pdf]. Though this research shows unexpected activity, that activity is still relatively mild compared to other central supermassive black holes in many other galaxies. Why this difference exists remains an unanswered question.

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