Nasa has revealed the first look of a full-scale prototype for six telescopes that will enable, in the next decade, the space-based detection of gravitational waves—ripples in space-time caused by merging black holes and other cosmic sources.
This advancement is part of the LISA (Laser Interferometer Space Antenna) mission, a collaborative effort between Nasa and the European Space Agency (ESA). The mission will utilize an array of spacecraft to measure minuscule changes in distance—down to picometers, or trillionths of a meter—across a vast configuration larger than the Sun itself. The triangular formation of spacecraft will span approximately 1.6 million miles (2.5 million kilometers) on each side.
Highlighting the crucial role of twin telescopes aboard each spacecraft, Ryan DeRosa, a researcher at Nasa’s Goddard Space Flight Center said, “Twin telescopes aboard each spacecraft will both transmit and receive infrared laser beams to track their companions, and Nasa is supplying all six of them to the LISA mission.”
Central to this initiative is the Engineering Development Unit Telescope, a prototype designed to inform the construction of the mission’s flight hardware. Manufactured and assembled by L3Harris Technologies in Rochester, New York, the prototype arrived at Goddard in May. Its primary mirror is coated in gold, enhancing the reflection of infrared lasers and minimizing heat loss in the cold vacuum of space. This feature is vital, as the telescope is optimized to function near room temperature.
The Engineering Development Unit Telescope is crafted entirely from a specialized amber-colored glass-ceramic known as Zerodur, produced by Schott in Mainz, Germany. This material is renowned for its thermal stability, ensuring minimal shape distortion over a wide range of temperatures—a critical characteristic for high-precision optical applications.
The LISA mission is set to launch in the mid-2030s, promising to expand understanding by exploring gravitational waves, which are ripples in spacetime caused by cataclysmic events like merging black holes and neutron stars.

Dodging stormy weather ahead of Hurricane Milton, SpaceX launched the European Space Agency’s $398 million Hera probe Monday on a follow-up flight to find out precisely how a moonlet orbiting a small asteroid was affected by the high-speed impact of NASA’s DART probe in 2022.

The launching was in doubt until the last moment, with thick clouds and rain across Florida’s Space Coast, fueled by moisture pulled in by the intensifying hurricane to the west.

But as the launch time approached, conditions improved enough to satisfy launch safety rules and NASA managers cleared the rocket for takeoff. Right on time, at 10:52 a.m. EDT, the Falcon 9’s first stage engines ignited with a burst of flame and the booster climbed smoothly away from the Cape Canaveral Space Force Station.

Liftoff came in the nick of time for several hundred European Space Agency managers, scientists, engineers and journalists who flew to Florida to watch the launch.

Hurricane Milton is expected to bring extreme winds and torrential rain to Florida’s Space Coast by Wednesday, a forecast that prompted NASA to stand down on plans to launch the agency’s $5.2 billion Europa mission to Jupiter and its ice-covered moon Europa on Thursday.

Instead, NASA announced late Sunday the rocket and it costly payload will remain in a SpaceX hangar at the base of launch pad 39A at the Kennedy Space Center until Milton passes by and safety personnel have a chance to inspect spaceport facilities for signs of damage.

The weather also has thrown a wrench into NASA’s plans to bring three NASA astronauts and a Russian cosmonaut back to Earth after a 217-day stay aboard the International Space Station.

Crew 8 commander Matthew Dominick, Mike Barratt, Jeanette Epps and cosmonaut Alexander Grebenkin had planned to undock Monday.

But NASA announced Sunday their departure would be delayed to at least Thursday because of the expected bad weather. Crew Dragon ferry ships require calm winds and seas in the Gulf of Mexico or the Atlantic Ocean to permit a safe splashdown.

Mission to an asteroid and its moon

In the meantime, despite an initially grim forecast, SpaceX was able to take advantage of a break in the weather to kick off Hera’s two-year voyage to the asteroid Didymos and its small moon Dimorphos.

The DART impact altered the 11-hour 55-minute orbit of the 495-foot-wide Dimorphos, shaving 31 minutes off the time needed to complete one trip around the parent asteroid Didymos. The test confirmed the feasibility of someday nudging a threatening asteroid off course before a possibly devastating Earth impact.

But a successful deflection would depend on a variety of factors, including when the threat was detected — the farther out, the better — and the asteroid’s composition.

ESA’s Hera probe will orbit the Didymos system and study both asteroids in detail with 11 high-tech cameras and other instruments, deploying two small “cubesat” satellites to study the interior structure of Dimorphos, assess the DART impact crater, the moon’s internal structure and composition.

The goal of the Asteroid Impact and Deflection Assessment, or AIDA, is to better understand the techniques that might be needed to prevent an Earth impact.

“The good news is no dinosaur killer is on its way to Earth during the next 100 years,” said 
Richard Moissl, director of ESA’s Planetary Defense Office. “We are safe from that scenario, but there are smaller ones, especially in this dangerous size, 50 meters and upwards, where it really threatens human life on the ground.”

The first step in planetary defense is detection, he said, followed by detailed observations to pin down the asteroid’s orbit and determine whether a collision with Earth is a possibility.

“For small objects, civil protection is the way to go,” he said. “But 50 meters (160 feet across) and larger, you really want this thing not to hit Earth, not to threaten population centers. And then step three comes into play, deflection.

“But again, it’s always good to know what you’re up against. And this is where Hera and DART come into play.”

Unlike most Falcon 9 flights, there were no plans to recover the rocket’s first stage. To give Hera the velocity need to break free of Earth gravity, the Falcon 9’s two stages were programmed to use up all of their propellants, leaving none in reserve for a powered first stage landing.

The flight plan called for two firings of the upper stage engine before Hera’s release to fly on its own one hour and 16 minutes after liftoff.

To reach Didymos and Dimorphos, Hera will have to execute a deep space thruster firing in November to set up a gravity-assist flyby of Mars in March, sailing within about 3,700 miles of the red planet. Along the way, the spacecraft will pass within 620 miles of the small martian moon Deimos.

“By swinging through the gravitational field of Mars in its direction of movement, the spacecraft gains added velocity for its onward journey,” Michael Kueppers, ESA’s project scientist, said on the agency’s website.

“This close encounter is not part of Hera’s core mission, but we will have several of our science instruments activated anyway. It gives us another chance to calibrate our instruments and potentially to make some scientific discoveries.”

After another deep space maneuver in February 2026, Hera will finally be on course to slip into orbit around Didymos the following October. The mission is expected to last about six months.

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.