Enlarge / The main body of NASA's Europa Clipper spacecraft is reflected in one of the mission's deployable solar array wings during testing at Kennedy Space Center in Florida. (credit: NASA/Frank Michaux)

For a while earlier this summer, it looked like NASA's flagship mission to study Jupiter's icy moon Europa might miss its launch window this year.

In May, engineers raised concerns that transistors installed throughout the spacecraft might be susceptible to damage from radiation, an omnipresent threat for any probe whipping its way around Jupiter. The transistors are embedded in the spacecraft's circuitry and are responsible for approximately 200 unique applications, many of which are critical to keeping the mission operating as it orbits Jupiter and repeatedly zooms by Europa, interrogating the frozen moon with nine science instruments.

The transistors on the Europa Clipper spacecraft are already installed, and removing them for inspections or replacement would delay the mission's launch until late next year. Europa Clipper has a 21-day launch window beginning October 10 to begin its journey into the outer solar system.

Enlarge / A "selfie" photo of China's Zhurong rover and the Tianwen-1 landing platform on Mars in 2021. (credit: China National Space Administration)

China plans to launch two heavy-lift Long March 5 rockets with elements of the Tianwen-3 Mars sample return mission in 2028, the mission's chief designer said Thursday.

In a presentation at a Chinese space exploration conference, the chief designer of China's robotic Mars sample return project described the mission's high-level design and outlined how the mission will collect samples from the Martian surface. Reports from the talk published on Chinese social media and by state-run news agencies were short on technical details and did not discuss any of the preparations for the mission.

Public pronouncements by Chinese officials on future space missions typically come true, but China is embarking on challenging efforts to explore the Moon and Mars. China aims to land astronauts on the lunar surface by 2030 in a step toward eventually building a Moon base called the International Lunar Research Station.

Enlarge / This artist's concept shows the possible appearance of ESA's RAMSES spacecraft, which will release two small CubeSats for additional observations at Apophis. (credit: ESA-Science Office)

For nearly 20 years, scientists have known an asteroid named Apophis will pass unusually close to Earth on Friday, April 13, 2029. But most officials at the world's space agencies stopped paying much attention when updated measurements ruled out the chance Apophis will impact Earth any time soon.

Now, Apophis is again on the agenda, but this time as a science opportunity, not as a threat. The problem is, there's not much time to design, build, and launch a spacecraft to get into position near Apophis in less than five years. The good news is there are designs, and in some cases, existing spacecraft, that governments can repurpose for missions to Apophis, a rocky asteroid about the size of three football fields.

Scientists discovered Apophis in 2004, and the first measurements of its orbit indicated there was a small chance it could strike Earth in 2029 or in 2036. Using more detailed radar observations of Apophis, scientists in 2021 ruled out any danger to Earth for at least the next 100 years.