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Dozens of lunar missions are planned over the next decade.
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But at the moment there is no satellite navigation system between the Earth and the Moon.
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NASA and ESA are developing ways to help rockets navigate autonomously to the moon.
When NASA’s Artemis 1 mission successfully orbited the Moon in November, it showed the world that humans are on their way back.
NASA and the European Space Agency aim to put their shoes on the moon by 2025 and set up a permanent lunar base in orbit within the next few years. China and Russia are also collaborating to set up a separate lunar base, with manned landings scheduled for 2036.
But right now there’s no GPS to get us there. Astronauts cannot navigate space alone, and each mission relies on expertly trained engineers who constantly direct missions from the ground.
This will quickly become unsustainable for missions swinging back and forth.
Space agencies are working to put satellite navigation in rockets traveling the 239,000 miles between the Earth and the Moon. They also plan to build a brand new navigational network around Moon. Here’s how.
The way space agencies navigate today is cumbersome and expensive
Today, the only way to get from point A to point B in space is to perform complex physics-based calculations tailored to each mission.
As the spacecraft moves through space, the only point of reference is the Earth. So it needs to send a signal back to Earth to understand where it is, which means there are huge blind spots.
NASA completely lost contact with Orion, the spacecraft used in the Artemis 1 mission, when it passed behind the Moon. For a few minutes, all the engineers could do was hold their breath and hope to see the spacecraft come out unscathed on the other side.
This is resource-intensive and expensive, Javier Ventura-Traveset, chief engineer of ESA’s Galileo Navigation Science Office, told Insider. (The US government supports GPS; Galileo is the European version).
What space exploration needs right now is a way for spacecraft to triangulate their position from space so that they can navigate autonomously without input from Earth.
Using Earth’s satellites to fly to the moon can help
Surprisingly, the cheapest way to take satellite navigation into space is to use satellites around the Earth, Elizabeth Rooney, senior engineer at Surrey Satellite Technology Ltd, told Insider. The company is working with ESA to develop satellite navigation in space.
There are several major problems with this approach. The most important of them is that these satellites are directed towards the Earth.
This means that most of the signal from the satellites is blocked and only a small part spills out. The bit that spills out is much weaker than the main signal, and gets even weaker farther from Earth.
Given all these limitations, it would seem impossible to use this signal to navigate to the moon. But engineers have spent decades developing sensitive detectors that could harness this signal from deep space.
And they succeeded.
In 2019, four satellites were able to determine their position in space using signals from terrestrial GPS satellites.
They were 116,300 miles away – about halfway to the Moon, Ventura-Traveset said.
We really need a way to go all the way to the moon autonomously
The next frontier is the detection of this signal on the second half of the journey. But Ventura-Traveset is confident.
ESA and NASA are refining their detectors that could use signals from Earth satellites and are ready to test them on upcoming lunar missions.
The ESA receiver, named NaviMoon, is scheduled to be launched aboard the Lunar Pathfinder satellite in 2025 or 2026. ESA predicts that NaviMoon should be able to pinpoint the satellite’s position to within about 60 meters (about 200 feet), Ventura-Traveset said.
The hope is that with this detector, the satellite will be able to navigate autonomously around the Moon, he said. It is also very light, weighing around 4 kilograms (8 lb) in total, and could replace many of the heavier devices on board a spacecraft.
NASA is also working on detectors, developed in collaboration with the Italian space agency. Their goal is to launch the first of these receptors to the lunar surface in 2024 as part of the Lunar GNSS Receiver Experiment.
There is a “bit of a friendly competitive race” between ESA and NASA to deliver the Earth’s satellite navigation signal to the moon, James Joseph “JJ” Miller, associate director of policy and strategic communications for the space communications and navigation program at NASA Headquarters, told Insider in interview.
Miller said many other countries have started investing in space navigation technology.
“Everyone understood that this is an emerging user that is not going to disappear, that we actually need to prepare and make cis-lunar space, all space between the Earth and the Moon, as robust and reliable as possible with these signals,” he said.
After all, we’re going to need a satellite navigation network around Moon
The signal from Earth’s satellites can take a spacecraft all the way to the moon, but once they’re on the surface, the signal won’t be of much use.
At this point, these signals can only reach what is visible from Earth, so the dark side of the moon and the moon’s poles are inaccessible.
So the plan is to give the Moon its own fleet of communications and navigation satellites, called the Moonlight Initiative. The first node in Moonlight would be NASA’s Pathfinder satellite.
Ventura-Traveset said ESA intends to test a basic Moonlight infrastructure by 2027, and a more comprehensive infrastructure by 2030.
NASA is also working on building its own network called LunaNet. NASA Gateway, a space station that the agency intends to send into lunar orbit, would be another node in the network.
“We would envision an architecture involving NASA and ESA satellites working together,” said NASA’s Miller.
Moon Settlers will need high speed internet
Bringing people back to the moon has a more commercial aspect. In the long term, lunar settlers would need to set up camp to mine minerals and water – which could be used to power rockets on their way to Mars.
Visitors to the Moon will need to be able to communicate with Earth, talk to each other effectively, and have fun, said Ventura-Traveset.
Further down the line, settlers on the moon could have access to high-speed internet, videoconferencing with loved ones on Earth, streaming shows, and creating their own content from space, Ventura-Traveset said.
“I don’t think anyone is saying that’s not the way we’re going,” Ventura-Traveset said.
Read the original article in Business Insider
