American space firms stayed away from Europe's space summit. The same week, NASA said it probably cannot build the radar it promised for a Venus orbiter.

The rest of the day

9 more stories on this beat.

Each with its own sources. None of these is a link to the story above.

1. 02

   Two European observatories lose their American parts

   NASA also promised hardware for two large European observatories and may not deliver either. LISA is a set of three spacecraft meant to measure gravitational waves, the tiny ripples in space that two black holes make when they merge. NASA was to build its lasers and ultra-stable telescopes. [1] New Athena would be the largest X-ray telescope ever flown, and NASA was down for its X-ray sensors, a cooler and a system to damp out vibration. [1] Both were tracking launches in the late 2030s. [1]

   Why it matters — Carole Mundell, who runs science at the European Space Agency, says its 23 member countries agreed last year to raise the science budget by 3.5% a year through 2028. That budget is about 750 million euros a year, a fraction of NASA's, and the agency is still working out how to fill these two gaps. [1]

2. 03

   Europe is being invited to fly with China instead

   Mundell says China has invited the European Space Agency onto more of its science missions, and that Europe is exploring it. [1] The two already fly together. Smile is a satellite that watches how the stream of particles from the Sun hits Earth's magnetic shield. It was built in China, launched on a European Vega-C rocket this year, and is a half-and-half project with the Chinese Academy of Sciences. [1][12] The first European instrument to land on the Moon got there in 2024 aboard China's Chang'e 6. [1]

   Why it matters — NASA is the European Space Agency's most enduring partner, and it is the partner now cancelling things. Every Chinese mission Europe joins is a mission NASA is not on. [1]

3. 04

   Solid fuel is what caps Europe's launch rate

   Christophe Bruneau, chief executive of the rocket maker ArianeGroup, told reporters on 7 September that the main stumbling block to launching more often is the supply of solid propellant. That is the packed fuel inside the strap-on boosters that shove the rocket off the pad. [5] He is discussing the ramp-up with the European Space Agency and a supply chain of about 600 companies. [5] The squeeze is tighter because demand has moved to the Ariane 64, the version with four boosters rather than two, and Europe's smaller Vega-C rocket burns the same motor. [4]

   Why it matters — A launch order can be signed in an afternoon and a propellant plant cannot. Whether Europe reaches twelve flights a year turns on a factory rather than on the order book. [4][5]

4. 05

   Europe asks whether to fly its own astronauts

   Josef Aschbacher, who runs the European Space Agency, put a question to the summit: should Europe build its own way of carrying astronauts to orbit? [3] European astronauts have flown for decades, always in American or Russian spacecraft. He says he hopes European leaders give him a mandate to develop the capability by the end of this year. [7] The Exploration Company, a French firm whose Nyx cargo capsule is in NASA safety reviews for a space station flight as early as November 2028, would start as a frontrunner. [7]

   Why it matters — Growing frustration with the United States as a reliable partner is what put the question on the agenda. [7] No government has put money behind it, and a spacecraft that carries people takes most of a decade to build.

5. 06

   Operators fear a gap when the Falcon 9 retires

   Emiliano Kargieman, chief executive of the imaging company Satellogic, said in Paris that Europe still has no cheap, frequent way to reach orbit while China has one. [3] Elon Musk has said SpaceX will wind down its Falcon rockets and replace them with the much larger Starship. [3] Industry executives worry the handover leaves a few years with too few flights to go round, which they call a launch crunch. [3] The Falcon 9 has already flown 104 times this year. [15]

   Why it matters — Almost every satellite plan for the late 2020s assumes the rocket that flies most often keeps flying. [3] If it stops before Starship is routine, everyone joins the same queue at once.

6. 07

   An American military satellite went up from California

   A Falcon 9 rocket lifted off from Vandenberg Space Force Base in California at 11:42 in the morning New York time on Thursday, carrying a mission called USSF-153. [16][15] The payload is classified: Space Systems Command, the US Space Force unit that buys launches, told Spaceflight Now that details about the mission are protected. [16] It was the 104th Falcon 9 flight of 2026 and the 27th for this booster, which landed on a drone ship in the Pacific. [15][16] The record for one booster is 37. [15]

   Why it matters — It was SpaceX's fifth national-security launch of the year. [16] Europe spent two days in Paris arguing over who can reach orbit, while the country that already can put up a satellite it will not describe.

7. 08

   Two European Earth-watchers are in the launch tower

   ESA's FLEX satellite and the European Union's Sentinel-3C have been rolled out inside their rocket nose cone to the launch tower at Europe's spaceport in French Guiana. [11] They lift off together on a Vega-C rocket, flight VV30, at 03:21 Central European Summer Time on 15 September. [9][11] FLEX carries an instrument that picks up the faint light plants give off while they turn sunlight into food, a glow the eye cannot see that changes with plant health. [10][11] Sentinel-3C measures oceans, land, ice and air. [10]

   Why it matters — The two fly in formation, so the plant glow can be read against cloud, temperature and land cover measured at the same moment. [10] ESA will replay the launch for reporters at its control centre in Darmstadt, Germany, that morning. [9]

8. 09

   Roman picks its first 118 observing programmes

   The support centre for NASA's Nancy Grace Roman Space Telescope has chosen the first round of observing programmes: 118 selected from 374 proposals. [14] They run from the solar system to the largest structures in the universe, and draw on the telescope's three core surveys of the sky, which a NASA committee recommended in April 2025. [14] Roman launched at the end of August on a Falcon Heavy rocket, cost $4.3bn, and carries a 300-megapixel camera with a field of view a hundred times wider than Hubble's. [8]

   Why it matters — A telescope does nothing until somebody decides where to point it, and 256 of the 374 proposals were turned down. [14] Roman is only the second NASA-led astrophysics mission to launch this century. [8]

9. 10

   ESA wants a name for its asteroid mission's dinosaur

   The European Space Agency has opened a public contest to name the cartoon dinosaur that is the mascot of Hera, its first planetary defence mission. [13] Hera is a spacecraft about the size of a small car, flying to Dimorphos, the asteroid that NASA's DART probe crashed into in September 2022. [13] The crash changed how long Dimorphos takes to circle its larger companion Didymos, but nobody knows what it did to the asteroid itself, so Hera will survey the site close up. [13]

   Why it matters — Turning one crash into a repeatable defence means measuring what the crash actually did. [13] ESA's planetary defence work also includes Ramses, which is to meet the asteroid Apophis when it passes Earth in 2029, and Neomir, which would watch for asteroids from orbit. [13]