Stormy weather has threatened to delay the launch of Europe’s Hera spacecraft, which is scheduled to blast off on Monday, SpaceX has said.
The probe will head off on a mission to inspect the damage a NASA spacecraft did to an asteroid when it smashed into it in 2022 during the first test of Earth’s planetary defences.
The Double Asteroid Redirection Test (DART) deliberately crashed into the pyramid-sized asteroid Dimorphos roughly 11 million kilometres (6.8 million miles) from Earth.
The fridge-sized spacecraft successfully knocked the asteroid well off course, demonstrating that humanity may no longer be powerless against potentially planet-killing asteroids that could head our way in the future.
But much about the impact remains unknown, including how much damage was done and exactly what the asteroid was like before it was hit.
So the European Space Agency (ESA) says it is sending Hera to the asteroid to conduct a “crime scene investigation” in the hopes of learning how Earth can best fend off future asteroids.
The spacecraft is scheduled to blast off on a SpaceX Falcon 9 rocket from Cape Canaveral in the US state of Florida at 10:52 am local time (1452 GMT) on Monday.
However thunderstorms have been forecasted in the launch area. SpaceX said on X on Sunday that the weather is currently only 15 percent favourable for a launch.
If a delay is required, a back-up launch is planned for Tuesday 10:46 am local time, SpaceX said.
The launch window for the mission will remain open until October 27.
– Green light after ‘mishap’ –
The launch had also faced a potential delay due to an anomaly involving a Falcon 9 rocket during the launch of SpaceX’s Crew-9 astronaut mission late last month.
But on Sunday, the US Federal Aviation Administration gave the green light.
“The absence of a second stage re-entry for this mission adequately mitigates the primary risk to the public in the event of a reoccurrence of the mishap experienced with the Crew-9 mission,” it said in a statement.
The launch window for the mission will remain open until October 27.
Once launched, Hera is planned to fly past Mars next year and then arrive near Dimorphos in December 2026 to begin its six-month investigation.
Dimorphos, which is actually a moonlet orbiting its big brother Didymos, never posed a threat to Earth.
After DART’s impact, Dimorphos shed material to the point where its orbit around Didymos was shortened by 33 minutes — proof that it was successfully deflected.
Analysis of the DART mission has suggested that rather than being a single hard rock, Dimorphos was more a loose pile of rubble held together by gravity.
“The consequence of this is that, instead of making a crater” on Dimorphos, DART may have “completely deformed” the asteroid, the Hera mission’s principal investigator Patrick Michel told a press conference.
But there are other possibilities, he said, adding that the behaviour of these low-gravity objects is little understood and “defies intuition”.
The 363-million-euro ($400 million) mission will be equipped with 12 scientific instruments and two nanosatellites.

Nasa is set to launch the SpaceX Crew-9 mission on Saturday, which will bring astronauts Sunita Williams and Butch Wilmore back to Earth after their extended stay aboard the International Space Station (ISS) since June. The spacecraft is scheduled to launch at 1:17 pm EDT (10:47 pm IST) from Cape Canaveral Space Force Station in Florida.
Live coverage of the launch will begin at 9:00 am EDT (6:30 pm IST) on Nasa’‘s official website, NASA+, and YouTube.The Crew-9 mission will be the first crewed launch from Space Launch Complex-40.
The spacecraft is set to dock with the ISS around 5:30 pm EDT (3:00 am IST) on Monday.
The Crew-9 mission is part of Nasa’s Commercial Crew Program. It includes Nasa astronaut Nick Hague and Roscosmos cosmonaut Aleksandr Gorbunov. Originally scheduled for September 26, the launch was delayed due to Hurricane Helene hitting Florida’s Gulf Coast.
Nasa posted on X that managers from Nasa and SpaceX were discussing the planned September 28 launch of the Crew-9 mission to the International Space Station, along with a weather update provided by Space Launch Delta 45.

In another post on X, Nasa mentioned a live panel on the International Space Station with Nasa leaders, where they would answer questions from digital creators attending the Crew-9 Nasa Social event, as well as questions submitted online using the hashtag #AskNASA.

The mission aims to transport Hague and Gorbunov to the ISS for a five-month stay and ensure the safe return of Williams and Wilmore. Hague and Gorbunov will stay on the ISS until February, coinciding with the next crew rotation. Astronauts Zena Cardman and Stephanie Wilson were also initially part of the Crew-9 mission but were removed to make room for the returning astronauts.
Williams and Wilmore traveled to the ISS in June on Boeing’s Starliner capsule for an eight-day mission. However, their stay was extended due to issues with the Starliner’s thrusters. Nasa then return the Starliner uncrewed on September 7 for further assessment.