SpaceX to raise $20 billion more by selling bonds

9:49 am

As part of its need for cash both to support its planned major capital projects and partly it appears to pay off some debt, SpaceX now plans to sell bonds in order to raise an additional $20 billion more.

The proceeds from the bond offering will mostly be used to refinance a $20 billion bridge loan SpaceX took in March as it prepared to go public. Such loans basically ensure that companies planning to go public have the money they would need to wait out an unfavorable turn in market conditions.

As the article at the link notes, however, SpaceX is hardly cash poor, having on hand over $100 billion after its initial public offering (IPO) of stock two weeks ago. On the surface this bond sale seems unnecessary, but I suspect its purpose is merely refinancing some already existing debt in order to save the company some money.

The propaganda press has been making much in the past week about the drop in SpaceX’s stock price following its original burst during the IPO, often spinning the drop as proof that SpaceX is not that valuable a company (see this NBC report for example). After raising to above $200 per share from its initial price of $135, it has since dropped to about $160. All of this is entirely normal. New stocks that capture the public’s interest all do this. The stock is simply now finding its natural market price, which by the way is still higher than that initial price.

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China’s Shenlong X-37B copy deploys a satellite

9:33 am

Shenlong in orbit shortly after launch
Shenlong in orbit shortly after launch.
Click for source.

According to data from the space surveillance company LeoLabs, China’s Shenlong mini-reusable shuttle — similar to the X-37B — deployed a object sometime before June 22, 2026.

At 02:30 UTC on 22 June 2026, LeoLabs detected an unknown object in the vicinity of the Chinese Shenlong reusable spaceplane.

This object did not correlate to any other object in our catalog. It was first observed by our Tracker radar in New Zealand.

This is not the first time a Shenlong in orbit released an object. On two previous flights in 2023 and 2024 it did the same. The Shenlong in orbit now was launched on February 7, 2026, the fourth mission of this X-37B copycat.

Overall, China has released very little information about Shenlong. We have no idea if the same or multiple Shenlongs have launched on the four known missions. No official pictures have ever been released, though the image of it to the right was apparently captured in orbit by amateur astronomers shortly after that February launch.

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Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

The print edition can be purchased at Amazon or any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

Scientists skeptical of dark energy fight back!

9:06 am

Will cosmologists every enter?
Will cosmologists every enter?

The uncertainty of science: In apparent direct response to the June 11, 2026 press release by cosmologists claiming that their data is correct and that the universe’s expansion is accelerating in the early universe and thus dark energy must exist, a different team of scientists today issued their own press release and research paper stating that the evidence of that acceleration is faulty and based upon a false assumption about supernovae.

The original discovery of dark matter and the acceleration was based on the brightness of a certain type of supernova in the early universe, which also assumed that brightness was always the same for every explosion. The new research says otherwise.

The team analysed the supernovae from the Pantheon+ dataset, one of the most comprehensive catalogues of its kind, and incorporated a recently proposed correction that takes into account the age of the stars that eventually produce these supernova explosions. They also checked whether the inferred acceleration of the expansion rate is indeed the same in every direction, as is assumed in the standard cosmological model. “There is increasing evidence that the brightness of Type Ia supernovae depends on the age of the stars they come from,” said Professor Sarkar, a co-author of the study. “If this effect is not accounted for, it can lead to the erroneous conclusion that the expansion rate is accelerating.”

After applying the correction, the researchers found that the data no longer support a picture of a uniformly accelerating universe. Instead, their analysis suggests that cosmic expansion is overall slowing down rather than speeding up.

Their conclusion is blunt: “There is thus no evidence for isotropic accelerated expansion of the Universe, which can be ascribed to either a Cosmological Constant or more general dark energy.”

In other words, there is solid disagreement within the cosmological community about the existence of dark energy. Some believe it exists, based on the supernova data. Some do not, because the data depends on too many assumptions about those supernovae that further observations suggest are wrong.

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Two launches by China and SpaceX

8:29 am

Since yesterday there were two more launches by the global rocket industry.

First, China placed a “communication technology experimental satellite” into orbit, its Long March 7A rocket lifting off from its coastal Wenchang spaceport. No other information was provided.

Artist's rendering of Starfall provided during today's live steam
Artist’s rendering of Starfall provided during today’s live steam

Next, SpaceX launched in the early morning the first demo mission for its Starfall recoverable capsule, its Falcon 9 rocket lifting off from Cape Canaveral Space Force Station in Florida. The company has released little information about this project, including not showing the deployment or splashdown of Starfall in the launch broadcast. Its short description of Starfall during the live stream made it sound very similar to Varda’s recoverable capsule, though larger. According to Wikipedia,

Starfall has a circular, disk-shaped form measuring 10′ in diameter and 2′ 6″ in height. Its empty mass is 2,100 kg (4,600 lb). Starfall carries up to 1,000 kilograms of payload in a volume of 2.5 by 0.5 meters and a total mass of about 3,100 kilograms. The vehicle consists of a top plate with maneuvering thrusters and a heat shield that jettisons before a parachute assisted splashdown. Starfall reaches orbit as a payload on Falcon 9 or Starship. The design focuses on precision delivery to specific locations, supporting rapid delivery for critical cargo.

The company has at this time provided no information about the results of this demo mission.

The rocket’s two fairings completed their 24th and 36th flights respectively. The first stage (B1078) completed its 29th flight (29 days after its previous mission), landing on a drone ship in the Atlantic. With this flight this booster moved past the space shuttle Columbia into a seventh place tie in the rankings for the most reused launch vehicle:

39 Discovery space shuttle
35 Falcon 9 booster B1067
34 Falcon 9 booster B1071
33 Atlantis space shuttle
33 Falcon 9 booster B1063
31 Falcon 9 booster B1069
29 Falcon 9 booster B1077
29 Falcon 9 booster B1078
28 Columbia space shuttle

Sources here and here.

The leaders in the 2026 launch race:

75 SpaceX
41 China
9 Rocket Lab (plus two suborbital HASTE launches)
8 Russia

For the third straight year SpaceX leads the entire world combined in total launches, 75 to 70.

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Conscious Choice cover

Now available in hardback and paperback as well as ebook!

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

 
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.

 

“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of the Mars Society.

 

All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. All editions can also be purchased direct from the ebook publisher, ebookit, in which case you don't support the big tech companies and the author gets a bigger cut much sooner.

 

Autographed printed copies are also available at discount directly from the author (hardback $29.95; paperback $14.95; Shipping cost for either: $6.00). Just send an email to zimmerman @ nasw dot org.

Botswana to sign the Artemis Accords

8:01 am

NASA yesterday announced that the Republic of Botswana will sign the Artemis Accords on June 25, 2026, becoming the 68th nation to join this American alliance in space.

The Republic of Botswana will sign the Artemis Accords during a ceremony at 9:30 a.m. EDT Thursday, June 25, at NASA Headquarters in Washington. NASA Deputy Administrator Matt Anderson will host Botswana’s Minister of Communications and Innovation David Tshere and U.S. Department of State Senior Advisor for Space Gregory Autry for the event.

Since NASA administrator Jared Isaacman took over, the NASA press releases announcing these signings have eliminated much of the pro-globalist language introduced during the Biden administration. No longer does NASA claim the accords are designed to “reinforce” the Outer Space Treaty. In today’s release the language is relatively vague, stating merely that the accords are

responding to the growing interest in lunar activities by both governments and private companies. The accords introduced the first set of practical principles aimed at enhancing the safety, transparency, and coordination of civil space exploration on the Moon, Mars, and beyond.

As the accords were originally conceived by Trump as a long term tool to overcome the Outer Space Treaty’s restrictions on private property and the establishment of American law in its colonies, this vagueness is likely intended to avoid antagonizing Russia and China, to lull them into apathy about the issue at this time. Later, when the U.S. Moon base is largely established expect that vagueness to fade. That will be the time to use the clout of this large alliance to force a major legal change in this international treaty.

The full list of nations in this American space alliance is as follows:

Angola, Argentina, Armenia, Australia, Austria, Bahrain, Bangladesh, Belgium, Brazil, Botswana, Bulgaria, Canada, Chile, Colombia, Cyprus, Czech Republic, Denmark, Dominican Republic, Ecuador, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, India, Ireland, Israel, Italy, Japan, Jordan, Latvia, Liechtenstein, Lithuania, Luxembourg, Malaysia, Malta, Mexico, Morocco, the Netherlands, New Zealand, Nigeria, Norway, Oman, Panama, Paraguay, Peru, Poland, Portugal, Romania, Rwanda, Saudi Arabia, Senegal, Singapore, Slovakia, Slovenia, South Korea, Spain, Sweden, Switzerland, Thailand, the Philippines, the United Kingdom, the United Arab Emirates, the Ukraine, the United States and Uruguay.

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Leaving Earth cover

Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.

If you buy it from ebookit you don't support the big oppressive tech companies and I get a bigger cut much sooner.

 

Winner of the 2003 Eugene M. Emme Award of the American Astronautical Society.

 
"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke

June 22, 2026 Quick space links

3:07 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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NASA IG: NASA’s launch infrastructure at Kennedy and Wallops needs attention

12:30 pm

Launch sites at Kennedy and Cape Canaveral
Figure 2 of IG report, annotated further by me.

According to a report released today [pdf] by NASA’s inspector general (IG), NASA’s launch infrastructure at both the Kennedy Space Center in Florida and the Wallops Flight Facility in Virginia are aging and need upgrades, but there is a systemic limitation on NASA’s access to funds to do the work.

The IG report — as is always expected from such a government report — of course whines about the lack of funding in recent NASA budgets, noting that Congress recently allocated $250 million for this purpose, but NASA claims it needs four times that amount, or $1 billion.

The report however also recognizes that this not the real problem. The map to the right, Figure 2 from the report, has been further annotated by me to show who is leasing or using each launch complex at both the Kennedy Space Center (managed by NASA) and Cape Canaveral Space Force Station (managed by the military but also supported significantly by NASA). As you can see, almost all launch sites are either leased by private rocket companies, or are being primed for future such leases. Yet, “statutory funding barriers” limit how much money NASA can collect from these companies. From the report’s conclusion:
» Read more

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Astronomers discover an asymmetrical radio galaxy distorted wildly as it plows into the surrounding galactic medium

9:49 am

Distorted radio galaxy
Figure 1 from the paper. Click for original.

Using ground-based radio telescopes, astronomers have now discovered a very strange asymmetrical radio galaxy squashed into a gigantic arc almost two million light years across as the galaxy pushes its way into the surrounding material of an even more gigantic galactic cluster.

In RAD-BAARG [the name they have given the galaxy], the researchers say one of the jets appears to interact with a large bow shock-like structure formed as the host galaxy falls through the surrounding hot gas toward a nearby cluster of galaxies. Similar to the shockwave formed ahead of a supersonic aircraft, a galaxy moving faster than the speed of sound in the surrounding intracluster medium can compress the ambient gas and generate a large-scale shock front.

The radio-emitting plasma from RAD-BAARG appears to illuminate this otherwise extremely faint structure, making it visible in low-frequency radio images, according to the team. The western side of the source contains a narrow jet feeding a sector-shaped emission region and a giant arc-like feature extending over nearly 560 kiloparsecs (1.8 million light years).

On the opposite side, the jet develops a distorted S-shaped morphology followed by a faint offset tail extending to almost 600 kiloparsecs. The overall structure suggests strong interaction between the radio plasma and the surrounding large-scale environment.

You can read their published paper here. The images to the right are figure 1 from that paper. The top image is just the radio data. The bottom image shows the contours of that radio data over the optical view. The cross marks the location of object’s host galaxy, as seen in the optical.

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Canada’s second proposed spaceport opens first rocket factory

9:03 am

Proposed Canadian spaceports
Proposed Canadian spaceports

The Canadian rocket startup Nordspace, which also hopes to operate the Atlantic Spaceport in Newfoundland, last week announced the opening of a new headquarters where it hopes to begin building its smallsat Tundra rockets.

The 60,000 square foot advanced manufacturing campus is dedicated to the production of the company’s light and medium-lift orbital launch vehicles alongside its space systems division, and represents a 10x expansion over NordSpace’s previous headquarters.

In reading between the lines of the press release, it appears this facility is mostly the company’s administrative and operations headquarters, though it is large enough to assembly two Tundra smallsat rockets at the same time, designed to put about three times more payload into orbit than Rocket Lab’s very successful Electron rocket.

Unlike Spaceport Nova Scotia, which was first proposed more than a decade ago and after years of struggle was leased in March by the Canadian government for $200 million, Nordspace has only been around since 2024 and has received a relatively small grant from the government, some portion of a $8.3 million program to support three Canadian rocket startups.

With both spaceports, there has been a lot of blarney spouted. Thus, separating the sizzle from the steak is difficult. No launch dates for Tundra have been provided, though the company says it has purchased the land for an even larger manufacturing facility, though once again it provides no timetables.

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Rocket Lab and SpaceX complete launches

9:49 am

In the past two days both Rocket Lab and SpaceX successfully completed launches.

I am reporting the Rocket Lab launch two days late because it was unannounced and remains officially unconfirmed by the company two days after lift-off. [UPDATE: Rocket Lab finally confirmed the launch on June 22, 2026.] According to two different launch tracking websites (here and here), the company’s Electron rocket lifted off successfully from one of its two New Zealand launchpads on June 19, 2026, placing a Rocket Lab payload into orbit dubbed Puma, a Space Force satellite designed to rendezvous with a target spacecraft dubbed Jackel that was built by the company True Anomaly and launched on an earlier SpaceX launch.

The mission secrecy was also for a second purpose, as outlined by Rocket Lab:

The $32 million contract includes a Rocket Lab spacecraft, configured for the unique requirements of the VICTUS HAZE mission, that will launch on Electron within just 24 hours’ notice. The mission is designed to improve Tactically Responsive Space (TacRS) processes and timelines to demonstrate the SSC’s ability to respond to on-orbit threats on very short timelines.

SpaceX then followed up today with a launch of 24 more Starlink satellites, its Falcon 9 rocket lifting off from Vandenberg Space Force Base in California. The first stage (B1063) completed its 33rd flight (70 days after its previous mission), landing on a drone ship in the Pacific. With this flight this booster moved into a tie with the space shuttle Atlantis for fourth place in the rankings for the most reused launch vehicle:

39 Discovery space shuttle
35 Falcon 9 booster B1067
34 Falcon 9 booster B1071
33 Atlantis space shuttle
33 Falcon 9 booster B1063
31 Falcon 9 booster B1069
29 Falcon 9 booster B1077
28 Columbia space shuttle
28 Falcon 9 booster B1078

Sources here and here.

The leaders in the 2026 launch race:

74 SpaceX
40 China
9 Rocket Lab (plus two suborbital HASTE launches)
8 Russia

For the third straight year SpaceX leads the entire world combined in total launches, 74 to 69.

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Katalyst’s Link rescue satellite goes airborne in advance of launch

9:26 am

Katalyst's proposed Swift rescue mission
Katalyst’s proposed Swift rescue mission.
Click for original image.

Katalyst’s Link rescue satellite — that will attempt to grab the Gehrels-Swift space telescope and raise its orbit — began its journey to its launch area over the south Pacific on June 18, 2026 when Northrop Grumman’s Pegasus rocket that will launch it was taken airborne by company’s Stargazer L-1011 airplane.

Stargazer, a modified L-1011 operated by Northrop Grumman, took off for Kwajalein Atoll, part of the Republic of the Marshall Islands in the South Pacific Ocean. Attached to the belly of the aircraft was one of the company’s Pegasus XL rockets with LINK inside.

…Stargazer will carry Pegasus and LINK to Kwajalein Atoll, part of the Republic of the Marshall Islands in the South Pacific Ocean with stopovers in California and Hawai’i.

Sometime later this month Stargazer will go to its launch area, climb to 40,000 feet, and release the Pegasus rocket, which will then ignite its engines to carry Link into orbit. Link will then attempt to rendezvous with Gehrels-Swift, using its robot arms to catch it (the telescope has no grapple attachment). If successful, it will then raise the telescope’s orbit so that it can resume observations for years to come.

The mission is daring in more ways than just described. Katalyst has never done this before. It is a startup that reconfigured its first demo mission into this rescue mission.

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June 19, 2026 Quick space links

2:40 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.

30 comments

The real history of the United States

12:44 pm

Out Where the West Begins

In August last year Diane and I made one of our many visits to the Grand Canyon. Along the rim near the Bright Angel trailhead there is a bookstore/gift shop. As we were not doing any hiking on this visit, merely touring the rim like millions of other tourists, we stopped in to browse the trinkets, art, and books. In doing so, I happened upon a two volume history of the American west by Philip Anschutz, entitled Out Where the West Begins.

At the time I was reading a biography of Cornelius Vanderbilt, the transportation giant of the 1800s who built Grand Central Station in New York and for a time owned and operated almost every railroad in the eastern United States (see my November 2025 review). That book was not only teaching me things about Vanderbilt I had never known, it was telling me something about basic American history that was never covered at all in my public schooling: The country was built by businessmen, free, competitive, aggressive, and largely ethical (though often with a streak of the scoundrel about them).

American public schools ignore this history. Instead, their lesson plans focus almost entirely on the politicians and economic and social background of our history. Though important for sure, the nation was not really built by those battles. Good politicians might have freed the slaves, or laid down the legal framework for settling the west, but most of what they did was violent or caused division. Economics and social studies merely provide context and background. It was people like Vanderbilt who did the actual construction, and they did if for profit.

As I was reading Vanderbilt’s biography last summer, I sensed this large gap in my knowledge of our country’s past. Who were the other businessmen and women who built our country? What obstacles did they face and overcome? I very much wanted those questions answered.
» Read more

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Texas Supreme Court rejects beach closure lawsuit against SpaceX

9:35 am

The Texas Supreme Court today unanimously rejected the lawsuit by fringe activist groups against SpaceX and the closure of beaches near Boca Chica for Starship/Superheavy launches.

Siding with SpaceX and the attorney general’s office, the Texas Supreme Court on Friday ruled that environmental groups did not have a right to sue to preserve public access to a beach that has been closed during rocket launches. The unanimous ruling said a trial judge properly dismissed the lawsuit with prejudice, meaning the groups could not refile it with changes.

The lawsuit was brought by SaveRGV, a very small group of leftist anti-Musk activists who have tried to use lawfare for the past five years to shut down Boca Chica. Later, the Sierra Club and the Carrizo/Comecrudo Nation of Texas joined in. The latter is a fake Indian tribe, as this tribe never existed in Texas at all, and is presently non-existent.

This decision essentially ends the lawfare campaign of these groups. I am sure they will try again, but their options continue to shrink, especially because they have practically no support in the southern Texas region. Everyone else is enthusiastically enjoying the prosperity and wealth SpaceX is bringing to the area.

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Problems during first drop tests of Europe’s Space Rider prototype

8:23 am

Artist rendering of Space Rider in orbit
Artist rendering of Space Rider in orbit. Click for original.

It appears that there was an undisclosed problem in May that prevented the first drop tests from a helicopter of a prototype of Europe’s Space Rider mini-reusable shuttle.

During a June 17 press briefing following the 347th ESA Council meeting, weeks after the aborted attempt occurred, ESA’s head of strategy and institutional launches for space transportation, Lucía Linares, explained that the agency could not provide a concrete date for the final drop test, stating only that it would take place after the summer and before the end of the year.

When asked what had prompted the several-month-long delay, an ESA spokesperson confirmed that the previously unannounced test campaign had taken place. According to the agency, the two-week campaign had concluded on 8 May, when the anomaly forced teams to abort the final test sequence. According to the spokesperson, the anomaly occurred during the captive ascent phase. During this phase, the mock-up was raised to drop height by a CH-47 Chinook helicopter. The agency did not, however, provide details about the nature of the anomaly.

This reusable capsule concept by the European Space Agency (ESA) is essentially a variation of either Varda’s returnable capsule or Boeing’s X-37B, but its development has been ridiculously slow. It was first tested by ESA in 2015. By 2017 the agency was promising it would be flying commercially by 2025. A decade later and they have not yet begun testing a full scale spacecraft.

Last summer ESA did helicopter drop tests of just the “brain” and parafoil. Now the drop tests this year of a full scale model — not the real thing — has been delayed until the end of this year because of an undisclosed “anomaly.”

When ESA finally does helicopter drop tests of the actual flight model remains completely unknown. Based on its pace of development, this reusable capsule won’t fly for another five to ten years. By then, a dozen companies will be flying their own private reusable capsules and spacecraft, as well as offering similar services on private space stations.

At that point ESA will likely cancel the program, after wasting two decades and more than a $100 million.

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SpaceX launches classified payload for National Reconnaissance Office

8:09 am

SpaceX in the early morning today successfully launched a classified payload for National Reconnaissance Office, its Falcon 9 lifting off from Vandenberg Space Force Base in California.

The number of satellites in the payload was not disclosed. The rocket’s two fairings completed their 3rd and 35th flights. The first stage completed its 3rd flight (29 days after its previous flight), landing back at Vandenberg.

The leaders in the 2026 launch race:

73 SpaceX
40 China
8 Russia
8 Rocket Lab (plus two suborbital HASTE launches)

For the third straight year SpaceX leads the entire world combined in total launches, 73 to 68.

4 comments

Final results from Lucy’s 2025 fly-by of asteroid Donaldjohanson: A tumbling peanut!

8:00 am

Lucy's gravitational field
Click for movie.

The science team for the asteroid probe Lucy yesterday published their final results from the spacecraft’s fly-by of the main belt asteroid Donaldjohanson in April 2025, outlining their present hypothesis based on the data as to the asteroid’s origins and evolution that has left it today a tumbling peanut.

The image to the right comes from a short animation showing the asteroid’s computed tumbling. The colors indicate the strength of its gravitational field, depending on slope. “Higher values (warmer colors) indicate steeper terrain relative to the local gravitational pull.” From the conclusion of their published paper:

We propose the following scenario for the formation and evolution of DJ [Donaldjohanson]. The parent body of the Erigone family was ≈80 km in diameter and was destroyed by a ≈20-km impactor at ≈155 [million years ago]. DJ’s bilobed shape probably arose from the accretion of fragments from this break-up event. This left DJ with an initial spin period of ≪10 hours.

The YORP effect [the pressure of sunlight] then slowed DJ’s rotation and shifted its spin axis toward low obliquity. After 20 to 60 [million years], DJ’s spin period reached ≈10 hours, causing slopes in the neck region to fail. The resulting widespread mass movement toward both lobes produced the ridge and smoothed the neck region.

Sometime later (<40 [million years ago), craters smaller than 0.4 km were globally erased, possibly owing to seismic shaking by an impact. Localized mass wasting on the neck continued, degrading the morphology of many craters without altering the small crater SFD. From 80 to 120 [million years] after formation, DJ’s rotation entered its current NPA [non–principal axis] state, with a spin period of 100 to 200 hours.

A more prosaic way of describing “non–principal axis state” is to say the asteroid is tumbling.

Lucy is presently on its way to the Trojan asteroids that orbit with Jupiter 60 degrees fore and aft of the gas giant. It will fly past ten Trojans during its mission, with the first the asteroid Eurybates on Aug. 12, 2027.

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