The Week in Space and Physics: Starship Reaches Space
On the second flight of Starship, a new hope for European spaceflight, the search for dark photons and the Mars Sample Return

The first time Starship flew, back in April, the rocket got less than halfway to space. Back then it struggled to get off the launch pad, blasted up huge chunks of concrete and suffered severe engine damage in the process. The flight itself tumbled out of control thirty miles high, failed to destroy itself on command, and then fell for forty seconds before exploding.
Attempt number two - which flew Saturday - went rather more smoothly. Lift-off was spectacular. The booster’s thirty-three engines lit without a flaw, powering the rocket majestically into the sky. For just under three minutes they burned, sending Starship soaring elegantly past the point of maximum pressure and well into the upper atmosphere.
Before lift-off, SpaceX had pointed to the separation of Starship and its booster as the biggest risk of the flight. Since the rocket should one day be reusable, that booster should fall back to Earth, relight its engines and bring itself to a smooth landing. The Starship spacecraft, meanwhile, should continue on its voyage, heading into orbit or beyond.
In the event, the separation seems to have worked more or less as expected. Certainly the two stages moved apart, leaving Starship soaring skyward and its booster falling back to Earth. Moments later, however, the booster violently exploded. Exactly why is still not clear - possibly the booster was damaged in the separation, or possibly the engines failed to reignite properly.
Starship itself flew onward for several minutes, reaching an altitude well above the official boundary of space. But here too problems seem to have occurred. Unusually, SpaceX showed no footage from cameras onboard Starship, but at some point - apparently thirty seconds before its engines should have cut out - it also exploded, putting an end to the flight.
According to SpaceX, that second explosion was triggered automatically by onboard safety systems. Details are still vague, but it does appear the spacecraft began to fly off course. In the worst case, that could have led it to fall back to Earth over a populated area.
Still, despite the two explosions, the flight was a certain success. SpaceX proved their ability to light and control all thirty-three booster engines. For the first time they sent Starship all the way into space. The launchpad - which was redesigned after suffering severe damage in the first launch - also seems to have held up well.
All this paves the way to another attempt soon. With the launchpad in good shape, and with few signs of regulatory issues, SpaceX should expect to be cleared for another launch early next year. That is good news for Starship, and good news for the future of America’s space program.
Europe Embraces NewSpace
Fifteen years ago NASA signed an agreement with two private companies to fly cargo to the International Space Station. It was an important milestone in the history of American spaceflight: one that opened the door for companies to compete to send astronauts into orbit, place landers on the Moon and build space stations of their own.
Two key ideas lay behind this initiative. On one side NASA was seeking to embrace competition, by encouraging companies to compete to deliver services. In theory this approach would offer lower costs and more options. A benefit shown, for example, by SpaceX’s success at sending astronauts to the Space Station, while Boeing’s effort still languishes on the ground.
But NASA was also trying to change the way it worked with companies. In the past the agency had focused on buying hardware - a rocket or a capsule - and then on putting it to use. This time, however, they brought a service - the delivery of cargo - and worried less about the exact hardware that would do it.
Europe’s space agency now wants to do something similar. At a summit in Seville, the agency announced plans to open contests for cargo delivery and rockets. Both seek to encourage a wave of new space companies in Europe, thus helping the continent keep up with the fast pace of activity in America and China.
Indeed, ESA’s Director General Josef Aschbacher has repeatedly warned that Europe is falling behind. Evidence of this is most obvious in the continent’s current rocket crisis. The Ariane 6, Europe’s new rocket - has been much delayed and seems unlikely to fly for another year at least. In the meantime Europe has been forced to turn to others - SpaceX chiefly - to launch their spacecraft.
How successful the effort will be remains to be seen, but Europe does have a rapidly growing private space industry. PLDSpace, a Spanish startup, recently launched their first rocket, and more - from Germany to Britain - are racing to do the same. Others are starting to plan capsules for cargo and even astronauts. ESA’s plans will hopefully turbocharge those efforts - and, as it does, boost the continent’s ambitions in space.
Searching for Dark Photons
For decades physicists have been hunting for dark matter here on Earth, and for decades they have been coming up empty handed. Partly that’s because we don’t really know what dark matter might look like. So far, indeed, the only evidence that it exists at all comes from studies of distant galaxies.
One idea posits the existence of an array of dark matter particles. There might, some speculate, be a hidden side to the universe, full of particles and forces that interact with each other but pass us by almost unnoticed. In the worst case these particles would show their presence only via the force of gravity - as we see in faraway galaxies.
That would make them almost impossible to detect in any Earthly experiment. To save the day, then, some physicists take their speculation a step further and talk of a “dark photon”. This particle, if it exists, would act as a link between our world and the dark world, emerging only in the aftermath of violent particle collisions. Yet whether this is really the case is unknown - so far, it should be said, there is little solid evidence of any dark matter particles or photons at all.
Still, if the dark photon is going to turn up anywhere, it will probably be at the Large Hadron Collider, the world’s largest particle collider. Over the past few years engineers have upgraded its capabilities, allowing it to collide more particles than ever before. They have also improved one of its instruments - the CMS detector - in ways that should make it more able to pick up any dark photons emerging from its collisions.
Sadly, an analysis of the most recent data from that experiment showed little sign of the photon. Like every other experiment in the hunt for a dark matter particle, this one has done little to shed light on the mystery.
Mars Sample Return on Pause
Western efforts to bring samples of Martian rocks back to Earth were put on hold last week, following reports that the projects would cost far more than hoped. Original plans put the cost of the mission at around four billion dollars and foresaw the arrival of Mars rocks in 2033. Yet in a recent report NASA concluded the true price would be closer to ten billion dollars, and that the target of 2033 was unrealistic.
As a result, the space agency has now paused work on the project. Getting it back on track will certainly mean revising the basic architecture of the mission and delaying some of its milestones. But the report also highlighted serious issues in the way NASA is running and managing the project - areas which should now be rethought.
China, meanwhile, has plans for a sample return mission of their own. Tianwen-3, currently planned for lift-off in 2028, would send a pair of spacecraft towards the Red Planet. Should all work out, that mission would return Martian rocks in 2031 - two years earlier than NASA’s most optimistic plans.