In ‘Space Notes, August 2025′ (ON, 17th August 2025), two weeks ago, I included images of the static firings of the Superheavy booster and Starship payload for Flight Test 10 of the combination, and last week I announced ‘stop press’ news that the launch had been scheduled for the same day, August 24th (our time).
Erection of the booster quickly followed, on the 21st (Fig. 1), followed by stacking of the Starship (Figs. 2 & 3), and confirmation that the flight profile would be almost a repeat of FT-9 (Fig. 4).
The launch attempt on Sunday 24th was postponed 12 minutes beforehand due to an oxygen leak in the ground supply system, and the second one 24 hours later was scrubbed at T minus 40 seconds due to an anvil cloud which was too close to the launch pad. Potential lightning activity has been treated with respect since Apollo 12 was struck twice after liftoff, when NASA was accused of having risked everything just to impress President Nixon (who cancelled the programme regardless, three years later).
Getting back up after midnight and waiting out the countdown three nights running was a bit of a strain, but more than justified by the third attempt on the morning of Tuesday 26th. The reason for watching in real time has been that after previous missions, SpaceX has had a tendency to release edited or cropped videos, rather than photographs, and replays are often cut off after a minute or so. (That practise in the media has been a source of complaint all the way back – I raised it as an issue in New Worlds for Old, 1979, and the BBC had been doing it for over a decade before that.) Putting together a complete flight sequence, e.g. for this column, has taken weeks if ever accomplished. Perhaps because of the success, this time Space.com published an almost complete set of images within two days, and my friend Chad Dixon, who has been assiduously combing the news, has filled in the gaps for me. I haven’t checked back through the previous nine missions, but I think this is the first time I’ve had a full sequence to show.
Not only was the launch precisely on time (“at the top of the launch window”, as commentators put it), but the entire flight sequence went off like clockwork, despite a lot of negative predictions on social media. Ignition of all 33 Raptor engines (Fig. 5) was followed by a smooth liftoff and climbout (Figs. 6 & 7).
I don’t have an image for ‘Max Q’, the moment of maximum dynamic pressure just after the vehicle passes the speed of sound, but although that’s a major milestone, there’s nothing to see then unless things go wrong – as they did with some of the early moonprobes, before the problem was identified. Since then the engines have routinely been throttled back to ease passage through Max Q, and it was a tragic irony that the last words from the Challenger were ‘Go at throttle-up’, when by that time they were very far from ‘Go’.
The next milestone was hot-fire staging and separation (Fig. 8), and again that was perfect, with the new programming of the release, first used last time, setting the booster on a faster return track to Earth than before (see ‘Flip Maneuver’ [sic] and ‘Boostback burn’ in Fig. 4). As on FT-9, the booster was over-stressed on its return and deliberately missed capture by the launch stand for that reason. However, one of the tests was deliberately to switch off one engine during the landing burn and restart another, to simulate an ‘engine-out’ during an actual capture, and the booster passed that with flying colours, making a smooth approach to the sea (Fig. 9).
The Ship was now in the second-stage boost phase labelled ‘Starship ascent’ in Fig. 4, and that was where the first two of the last three flights experienced fuel leaks and fires leading to ‘rapid unscheduled disassembly’.
Nothing like it occurred this time (Fig. 10): notice the graphic at bottom right, showing the attitude of the Ship and all six engines alight (three normal Raptors and three inner Vacuum Engines, specialised for use in space). At cut-off the Ship was placed in a ballistic trajectory, rather than in orbit, to ensure that it didn’t overfly its Indian Ocean target and come down in Australia, as Skylab did unintentionally in 1979. Notice the different graphic at bottom right of Fig. 11, Figs. 13-14 and 16-17, with a white dot tracing the Ship’s progress around the globe – actually in the wrong phase, because Africa was in darkness at the time.
The next scheduled event, not shown during the ‘Coast phase’ of Fig. 4, was to be the deployment of eight dummy Starlink satellites, as one commentator said “basically just steel plates”, rehearsing for commercial deployments later in the programme. During the run-up to one of the scrubbed launches Elon Musk was in the studio, talking to the presenters about the growth potential of Starlink and the much larger versions to be launched by Starship once it’s fully operational. The demand for worldwide broadband is unquestioned, with 6 million users now in 150 countries “and counting”. Some encouraging news of late is that attempts are being made to develop an interruptor system, which will redirect Starlink signals through other satellites, not to interfere with ground-based radiotelescopes (See Stefanie Waldeck, ‘Scientists analyze 76 million radio telescope images, find Starlink satellite interference “where no signals are supposed to be present”‘, Space.com, online, July 28th, 2025: Tereza Pultarova, ‘SpaceX partners with astronomers to protect radio astronomy from satellite interference’, Space.com, August 20th 2025). SpaceX’s experiments to reduce the optical brightness of their satellites have had ‘mixed success’, but at Surrey Nanosystems, a company formed at the University of Surrey, a new paint called Vantablack 310 may be able to reduce light pollution by satellites by 99%. It’s to be tested on a student satellite called Jovian 1, which will carry a range of payloads built by British universities to low Earth orbit next year. (Tereza Pultarova, ‘Coating satellites with super-dark Vantablack paint could help fight light pollution crisis’, Space.com, June 10th, 2025). I have heard from one expert source that the patent holders of Vantablack may make it too expensive for satellite makers to use, but we must hope for better than that; and where there’s one solution, as I argued in my ‘Politics of Survival’ (ON, 9th, 16th and 23rd February, 2nd March, 2025), there may be others.
Several previous attempts to launch dummy Starlinks from Starships have been frustrated, for instance by problems with the launching bay door, and last time, by FT-9’s loss of attitude control after a pressure vessel explosion in the nose. This time, depressurisation was successful, and interestingly, unlike last time’s swirling ice crystals that shouldn’t have been there, bands of mist could be seen forming and dispersing as the pressure went down. That was foreseen as far back as 1956, in the junior version of Jeff Hawke for Express Weekly, where unconscious astronauts were rescued from a partially decompressed spaceship cabin (Fig. 11). Watching the releases both long-distance and in close-up, it seemed to me that there was excessive vibration in the deployment mechanism, and no doubt that will be smoothed out in future, but all eight of them were successfully released (Figs. 12-15). There were no views from external cameras to be relayed by active Starlinks (note ‘powered by Starlink’ at the top right of Fig. 12), because the releases were in darkness over the Atlantic.
Next scheduled was a relight of just one of the central engines, simulating a launch tower capture to come on later flights. Again that was completely successful (Fig. 16); although its indicator light has not come on in the corner graphic, the ring surrounding it correctly shows how brief the ignition was – so much so that I looked away for a moment and missed it.
One reason for the brevity was to keep the landing on target, where a camera buoy was waiting to record the splashdown, as they had done on the early flights. Like the Superheavy entry, the Starship one was deliberately overstressed to test its limits, as well as testing various types of heat-absorbing tiles and leaving some off to test damage to the hull.
Sure enough, as the re-entry continued damage occurred to the skirt protecting the engines (Figs. 17 & 18; “Not what we want to see”, said the SpaceX commentator, meaning ‘not on normal flights’, and towards the end burn-through was noted on the after end of the fins (Fig. 19).
Nevertheless, the landing burn was successful (Figs. 20-25), and a lot of attention is being paid to how well the vehicle withstood its ordeal.
As Space.com remarked, “The vehicle’s belly appears to have been toasted golden-brown by the heat of reentry. [‘Never a frown’ then – DL.] Ship sports other battle scars as well; several chunks are missing near its base, which looks a bit like the ear of a dog that lost a fight.” There will have to be considerable improvement on that, if the Starships are to be captured by the launch towers for refurbishment in place for relaunch. Five such towers are now in preparation: two at Starbase in Texas, one on Pad 39 at Kennedy Space Centre, and two more on Pad 37 in the Space Force Base, formerly Cape Canaveral Air Force Station – see the historical layout of Fig. 26.
Meanwhile preparations continue for the first crewed flight to the Moon since December 1972, with the Artemis II mission currently scheduled for some time between February and May next year. The crew have now done a full dress launch rehearsal, realistically conducted at night because that’s what’s anticipated. Leaving the Neil Armstrong Operations & Checkout Building at KSC on August 11th, 2025, they went to the Vehicle Assembly Building and in there along a swing arm, like the one on the launch tower, before entering the Orion capsule for the first time in a full launch simulation (Figs. 27-29).
They’ve also been practising exit from the capsule after water landing following a launch emergency (Fig. 30), and NASA has now unveiled the new state-of-the-art control room at Johnson Space Centre, to be used for the first time in the Artemis II mission (Fig. 31).
And finally… China has released more pictures and film of its lunar lander tether tests (Fig. 32, see ‘Space Notes, August 2025’, above), and has conducted a first stage test firing of their Long March 10 booster (Fig. 33), which will be intended to take the taikonauts to the Moon – currently planned for around 2030, but if the race hots up, who knows?
Duncan Lunan’s recent books are available from bookshops and through Amazon; details are on Duncan’s website, www.duncanlunan.com.