Enlarge / NASA's Orion spacecraft descends toward the Pacific Ocean on December 11, 2021, at the end of the Artemis I mission. (credit: NASA)

NASA officials declared the Artemis I mission successful in late 2021, and it's hard to argue with that assessment. The Space Launch System rocket and Orion spacecraft performed nearly flawlessly on an unpiloted flight that took it around the Moon and back to Earth, setting the stage for the Artemis II, the program's first crew mission.

But one of the things engineers saw on Artemis I that didn't quite match expectations was an issue with the Orion spacecraft's heat shield. As the capsule streaked back into Earth's atmosphere at the end of the mission, the heat shield ablated, or burned off, in a different manner than predicted by computer models.

More of the charred material than expected came off the heat shield during the Artemis I reentry, and the way it came off was somewhat uneven, NASA officials said. Orion's heat shield is made of a material called Avcoat, which is designed to burn off as the spacecraft plunges into the atmosphere at 25,000 mph (40,000 km per hour). Coming back from the Moon, Orion encountered temperatures up to 5,000° Fahrenheit (2,760° Celsius), hotter than a spacecraft sees when it reenters the atmosphere from low-Earth orbit.

Enlarge / The flight hardware core stage for Europe’s new rocket, Ariane 6, is moved onto the launch pad for the first time this week. A launch is possible some time this summer. (credit: ESA-M. Pédoussaut)

Welcome to Edition 6.41 of the Rocket Report! As I finish up this edition I'm listening to the post-Flight Readiness Review news conference for Boeing's Crew Flight Test. It sounds like everything remains on track for a launch attempt on May 6, at 10:34 pm ET. It's exciting to see this important milestone for Boeing and the US human spaceflight program so near to hand.

As always, we welcome reader submissions , and if you don't want to miss an issue, please subscribe using the box below (the form will not appear on AMP-enabled versions of the site). Each report will include information on small-, medium-, and heavy-lift rockets as well as a quick look ahead at the next three launches on the calendar.

Shetland spaceport advancing toward launch . SaxaVord Spaceport in Scotland is on track to launch the United Kingdom’s first vertical rocket into orbit, the BBC reports . The Civil Aviation Authority has granted a range license to the Scottish spaceport, which will allow the company to control the sea and airspace during launch. Previously, the site received a spaceport license in December 2023. Ambitiously, the facility aims to launch up to 30 rockets every year.

Enlarge / A meeting of the UN Security Council on April 14. (credit: Fatih Aktas/Anadolu via Getty Images )

Russia vetoed a United Nations Security Council resolution Wednesday that would have reaffirmed a nearly 50-year-old ban on placing weapons of mass destruction into orbit, two months after reports Russia has plans to do just that.

Russia's vote against the resolution was no surprise. As one of the five permanent members of the Security Council, Russia has veto power over any resolution that comes before the body. China abstained from the vote, and 13 other members of the Security Council voted in favor of the resolution.

If it passed, the resolution would have affirmed a binding obligation in Article IV of the 1967 Outer Space Treaty, which says nations are "not to place in orbit around the Earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction."

Enlarge / The author tries not to crash a lunar rover. (credit: Eric Berger)

As a SpaceX engineer working on the Starship program about five years ago, Jaret Matthews could see the future of spaceflight quite clearly and began to imagine the possibilities.

For decades everything that went to space had to be carefully measured, optimized for mass, and serve an extremely specialized purpose. But Starship, Matthews believed, held the potential to change all that. With full reusability, a barn-size payload fairing, and capability to loft 100 or more metric tons to orbit in a single throw, Starship offered the tantalizing prospect of a world in which flying into space was not crazy expensive. He envisioned Starships delivering truckloads of cargo to the Moon or Mars.

Matthews spent a decade working on robots and rovers at NASA's Jet Propulsion Laboratory before coming to SpaceX in 2012. He began to suggest that the company work on a system that could unload and distribute cargo from Starship, like the cranes and trucks that offload cargo from large container ships in port. However, he didn't get far, as SpaceX was focused on developing the Starship transportation system.

Enlarge / SpaceX landed its 300th booster on Tuesday. (credit: SpaceX webcast)

SpaceX launches have become extremely routine. On Tuesday evening, SpaceX launched its 42nd rocket of the year, carrying yet another passel of Starlink satellites into orbit. Chances are, you didn't even notice.

All the same, the cumulative numbers are mind-boggling. SpaceX is now launching at a rate of one mission every 2.7 days this year. Consider that, from the mid-1980s through the 2010s, the record for the total number of launches worldwide in any given year was 129. This year alone, SpaceX is on pace for between 130 and 140 total launches.

But with Tuesday evening's mission, there was a singular number that stood out: 300. The Falcon family, which includes the Falcon 9 and Falcon Heavy boosters, recorded its 300th successful first-stage landing.