What time is it on the moon?
Since the dawn of the space age, the answer has been: it depends. For decades, lunar missions have operated on the time of the country that launched them. But with several lunar explorations heading to the launch pad, the European Space Agency has deemed the current system unsustainable.
the solution the agency said last weekis a lunar time zone.
“ESA is not taking the lead in this discussion, we are just pointing out a problem that we need to address,” said Brice Dellandrea, an ESA engineer. “But this is the kind of issue that needs international coordination and consensus.”
The main goal of establishing a universal timing system for the moon, ESA said, is to streamline contact between the various countries and entities, public and private, that are coordinating trips to and around the moon.
The discussion about how to do that is happening as things start to get busy on and above the lunar surface.
The M1 lunar lander built by the Japanese company Ispace it is scheduled to reach the moon in april, when it will try to deploy a rover built by the United Arab Emirates; a robot built by Japan’s space agency, JAXA; and other payloads.
A cylindrical, six-legged robot called the Nova-C lander, built by Houston-based company Intuitive Machines, is expected to launch on SpaceX’s Falcon 9 and Land at the South Pole of the moon in June. Additional unmanned missions will land by the end of the year, according to jack burndirector of the Space Science and Exploration Network at the University of Colorado, Boulder.
Those missions, among other possible moon landings, are happening as NASA prepares to send four astronauts into orbit of the moon next year. That mission will pave the way for the first manned moon landing since Apollo 17 in December 1972, currently scheduled for 2025.
Meanwhile, the European Space Agency is contributing to NASA’s effort to build the Gateway Lunar Station, which will serve as a way station for future crews on their way to the lunar surface. China last year completed construction of its own space station and previously hinted that Chinese astronauts would be on the moon by 2030. South Korea launched its own lunar spacecraft, Danuri, on a SpaceX Falcon rocket from Florida in August. It joined India’s Chandrayaan-2 mission, as well as NASA and Chinese spacecraft, in its lunar orbit.
With further exploration comes the potential for miscommunication.
“These missions will not only be on or around the Moon at the same time, but will also often interact, potentially relaying communications with each other, conducting joint observations or conducting rendezvous operations,” ESA said in a statement. For all those interactions to happen smoothly, the missions will need to operate on a standardized time, the agency said.
“This idea of timing on the moon is important because it shows the international development of the moon,” Dr. Burns said. “Precision timing was key to navigation on Earth, and it is key to navigation between Earth and the Moon.”
ESA said a universal timing system for the moon is needed, but many details remain to be worked out. One of the questions that has yet to be resolved, the agency said, is whether lunar time should be set on the moon or in sync with Earth.
Atomic clocks accurately keep time on Earth, but synchronizing time on the Moon is tricky because clocks run faster there, gaining about 56 microseconds, or millionths of a second, per day.
Once a new lunar time zone is established, the methods used to create it will be useful for future space exploration, says Dr. Burns said. Astronauts could go to Mars in the next two to three decades, he said, and will face logistical hurdles similar to those a Martian time zone might face.
“We will be an exploration civilization where we will explore beyond Earth’s orbit,” Dr. Burns said. “We’re going to go to the moon and then after that to Mars.”
kenneth chang contributed reporting.