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NASA’s latest tiny lunar probe is battling a steering engine glitch on its way to the moon.
A spacecraft called the Lunar Flashlight launched last month on a mission to search for water ice on the moon. The spacecraft was also supposed to test a new “green” fuel on a four-month trip to the moon, but its engines have a problem, NASA reported Thursday (January 12).
“While the small satellite is largely healthy and communicating with NASA’s Deep Space Network, the mission operations team has found that three of its four jet engines are performing less well,” NASA wrote in an update. (opens in a new tab). “Based on ground testing, the team believes that the poorer performance may be due to obstructions in the fuel lines that may restrict fuel flow to the jet engines.”
Related: NASA’s lunar water hunting satellite Lunar Flashlight explained
A SpaceX Falcon 9 rocket launched the Lunar Flashlight spacecraft to the moon on December 11 along with a Japanese lunar lander carrying a lunar rover built by the United Arab Emirates. NASA’s small satellite is designed to search for water ice at the moon’s south pole, where NASA hopes to land astronauts in just a few years.
Lunar Flashlight flight controllers noticed problems with the probe’s propulsion system about three days after launch, when it became clear that it was moving with reduced thrust, NASA officials said. Now mission engineers are developing new plans to fire the jet engines longer to complete the Lunar Flashlight’s journey to the moon.
“The team plans to use the jet engines for a much longer period of time soon, hoping to clear any potential obstructions in the jet fuel lines while performing trajectory correction maneuvers that will keep the small satellite on course to reach its planned lunar orbit,” NASA wrote in a Thursday update. “In the event that the propulsion system cannot be restored to full capacity, the mission team is developing alternative plans to perform these maneuvers using the propulsion system with its current reduced thrust capability.”
It will be difficult recovering the Lunar Flashlight, which is about the size of a briefcase. The spacecraft “will need to perform daily trajectory correction maneuvers starting in early February to reach lunar orbit in about four months,” NASA wrote. The spacecraft fires its engines in short bursts, each lasting a few seconds. It uses a pink fuel known as Advanced Spacecraft Energetic Non-Toxic, which is intended to be less toxic than the hydrazine propellant found in most spacecraft.
The Lunar Flashlight mission requires the spacecraft to enter a wide, looping orbit around the Moon that will bring it within 9 miles (15 kilometers) of the surface at its closest point and send it to within 43,000 miles (70,000 km) of the moon at its farthest point . (The orbit is similar to that currently being tested by NASA’s CAPSTONE spacecraft and will be used by the agency’s Gateway Station for astronauts in the future.)
From its orbit, Lunar Flashlight will use four infrared lasers and a new type of laser reflectometer to search for surface ice in the permanently shadowed craters of the Moon’s south pole. The spacecraft is also testing a new low-power on-board computer called the Sphinx, which has been specially designed to be radiation-resistant in the harsh environment of space. Its new Iris radio is also expected to test ultra-precise navigation systems for future small probes headed to other destinations in our solar system, NASA said.
Lunar Flashlight isn’t the only NASA lunar probe to have problems right after launch.
The CAPSTONE Cube suffered its own woes, losing contact with Earth shortly after separating from Rocket Lab’s electron booster in July. The spacecraft also began to fall in space after an engine burnt out in September. The mission operations team, led by Colorado-based company Advanced Space, was able to resolve both glitches, allowing CAPSTONE to reach its final orbit in November.
Email Tariq Malik at tmalik@space.com or follow him @tariqjmalik (opens in a new tab). Follow us @Spacedotcom (opens in a new tab), Facebook (opens in a new tab) and Instagram (opens in a new tab).
