Insights into the cause of Starship's testing explosion, successful opening of a recently retrieved sample container from the Bennu asteroid, and private astronauts en route to the space station. This Week in Space

Last Friday, Japan became the fifth country to successfully land a spacecraft on the moon, with the landing of the unmanned SLIM spacecraft by the Japan Aerospace Exploration Agency. The lunar lander was launched into space in September 2023 as a secondary payload during the launch of the XRISM space telescope. Following a nearly four-month journey on a fuel-efficient trajectory, it entered lunar orbit at the end of December. On Friday it began a maneuver for a particularly precise landing, utilizing advanced navigation technologies and real-time computerized analysis of ground images, to pinpoint the spacecraft's exact location.

The Japanese spacecraft, roughly the size of a car, was set to make an attempt at landing on the outer edges of the Shioli crater, a 300-meter diameter impact crater within a larger crater, on the near side of the Moon, about 13 degrees south of its equator. The landing itself was expected to be unconventional as the spacecraft was designed to stabilize on its side, with the landing engine facing sideways rather than facing the ground.

The lunar lander is expected to operate for the duration of one lunar day, which is equivalent to about two weeks on Earth, and to carry out measurements with its instruments and capture images to gather information about the ground composition in the area. Additionally, the mission was designed to deploy two tiny vehicles – one designed to advance by hopping across the moon's surface, and the other a robot slightly larger than a tennis ball, both of which will capture close-up pictures of the lunar surface.

With the successful lunar landing, Japan became the fifth country to land a spacecraft on the moon, after the Soviet Union, the United States, China, and India, which achieved this feat only last summer. In April last year, the Hakuto-R spacecraft by the Japanese company iSpace crashed during a Moon landing attempt, causing Japan to miss the chance to precede India and to achieve the first landing of a private spacecraft on the Moon. Less than two weeks ago, Astrobotic, another company, failed in its attempt to be the first to land a private spacecraft on the Moon, due to a fuel leak in its Peregrine lander. Next month, another American company, Intuitive Machines, is expected to launch its own lander to the moon, and in May, China is planning a particularly ambitious mission: to bring back the first soil samples from the far side of the moon.

A particularly precise landing, directed sideways. Simulation of the Japanese SLIM mission:

Why Did Starship Explode?

SpaceX's massive spacecraft, Starship, made its first journey into space  two months ago during its second trial, but it turned out to be a very brief visit. Even shorter than anticipated. The spacecraft exploded at an altitude of 150 kilometers, just minutes before it was supposed to shut down its engines and continue on a brief suborbital flight, before re-entering Earth’s atmosphere over Hawaii. In recent days, SpaceX's CEO, Elon Musk, disclosed that the explosion was due to the deliberate release of excess oxygen, a necessary step due to the absence of a payload on the spacecraft. “If it had a payload, it would have made it to orbit because the reason that it actually didn’t quite make it to orbit was we vented the liquid oxygen, and the liquid oxygen ultimately led to a fire and an explosion.” Musk stated in a conversation with SpaceX employees that was shared on social networks.

Starship's six engines, along with the 33 engines of its Super Heavy launch vehicle, operate on methane and oxygen. Musk's statement implies that with a payload on board, the spacecraft would have utilized all its fuel, and there would have been no need to vent the excess oxygen. However, he did not explain how the release of oxygen led to the explosion, nor did he address the subsequent explosion of the rocket itself shortly after detaching from the spacecraft.Nevertheless, he expressed confidence in the company's ability to succeed in Starship's next trial, scheduled for February of this year. “I think we’ve got a really good shot of reaching orbit with Flight 3,” said Musk

He also mentioned that in this upcoming trial, there are plans to activate the spacecraft's engines in space, to demonstrate its capability to maneuver during re-entry into Earth's atmosphere. Additionally, there is a planned experiment of transferring liquid fuel from one tank to another, to test the feasibility of in-space refueling, which is an important component of Starship's role in the Artemis program, intended to land humans on the Moon once again. Starship was chosen as the lunar landing vehicle, while other Starship spacecraft are intended to serve as refueling vessels. Also, during the next test flight, Starship is expected to test a new device for deploying Starlink satellites into space, as part of the expansion of SpaceX's satellite internet network. The device is intended for the larger and newer V2 model satellites that Starship is slated to deploy into orbit.


A promising start that ended in two explosions. Separation of the Starship spacecraft from the Super Heavy launch vehicle during the spacecraft's second test flight in November 2023 | Photo: SpaceX

Delayed Opening

Nearly four months after the sample from the asteroid Bennu arrived on Earth, scientists finally succeeded at opening the inner sample container. NASA's OSIRIS-REx mission collected the sample from the asteroid in October 2020, and in September 2023, the spacecraft dropped the sealed capsule in the Utah desert. Scientists from NASA and the University of Arizona  had successfully collected about 70 grams of sample from the outer part of the collection container,  an achievement that already defined the mission as a success. However, they encountered difficulties when attempting to open the inner container due to two of the 35 screws sealing it being damaged. To overcome this challenge, the agency had to design new tools specifically for the task, using materials that would not contaminate the sample or react with its components. After developing non-magnetic stainless steel tools, they were tested on a replica of the sample container. Only after successful testing were they introduced into the clean room, where they finally succeeded in opening the stubborn inner container. The material inside the container will first be documented by photography, and only then will scientists proceed to weigh it and report on the amount of material collected from the asteroid during the mission. Preliminary research on the material from the outer part has already provided interesting insights into the asteroid's composition.


Against all odds, we finally managed to open it. A NASA engineer uses the new tool to open the container.  Photo: NASA

The First Turkish Astronaut

A third crew of private astronauts was expected to fly to the International Space Station at the end of the week, as part of the AX-3 mission of Axiom Space, which is constructing a private space station based on the existing ISS. Similar to the previous two missions, participants paid an estimated amount ranging from 50 to 60 million dollars. However, this time, the funding did not come directly from the passengers themselves but was provided by their employers - European space agencies.

The mission will be commanded by veteran astronaut Michael López-Alegría, who currently serves as Axiom's chief astronaut. López-Alegría also commanded the first private astronaut mission to the station, which included Israeli astronaut Eytan Stibbe. Joining him are Italian pilot Walter Villadei, who has previously made a brief visit to space on a suborbital flight with Virgin Galactic, Swedish astronaut Markus Wandt, who flew with joint funding from Sweden and the European Space Agency (ESA), and Turkish fighter pilot Alper Gezeravcı, who is set to become Turkey's first representative in space.

The three private astronauts are expected to conduct numerous experiments during the mission, in medicine, biology, physics, as well as experiments designed to test equipment and materials for space use. These include experimenting with the use of artificial intelligence to assist in managing the crew's schedule, as well as testing a method for heating pasta in space.


The first private European astronaut mission. From right: Gezeravcı, Villadei, López-Alegría, and Markus Wandt | Photo: Axiom Space