So many things were brought into space this year: six people traveled aboard commercial vehicles, three spaceships began their journey to Mars, and several hundred distracting satellites rose into the sky.
On May 30th, SpaceX brought two astronauts from Cape Canaveral, Florida, to the International Space Station. It marked the first human launch on a commercial spacecraft and the first time astronauts have flown from a U.S. launch pad since the space shuttle was retired in 2011 (SN: 20.06.20, p. 16).
As part of its commercial crew program, NASA funded private space companies, including SpaceX and Boeing, to develop ways to transport astronauts to and from the space station so the agency no longer has to rely on the Russian Soyuz ship.
When the astronauts returned safely to Earth on August 2nd, the test of the SpaceX Crew Dragon was considered a success. The next flight, which took off on November 15, took in four astronauts. “I think it could be said that we really don’t depend on Soyuz anymore,” says astrophysicist and space historian Jonathan McDowell of the Harvard & Smithsonian Center for Astrophysics in Cambridge, Massachusetts.
Trip to mars
Three spaceships that left for Mars in July are scheduled to arrive in February 2021. The Perseverance Rover, NASA’s fifth Mars rover (SN: 7/4/20 & 7/18/20, p. 30th) will search a dry river delta for signs of old life and collect rock samples that a future mission will bring to earth.
China and the United Arab Emirates hope this year’s missions will mark their first successful trips to the Red Planet (SN Online: 07/30/20). After entering Mars orbit, China’s Tianwen-1 spacecraft is expected to drop a lander and rover onto the planet’s surface in April. China plans to bring back samples from Mars in the next decade, and Tianwen-1 is a tech demo for that mission. The rover will also look for hidden pockets of water under the surface and explore the geology and chemistry of Mars.
The UAE space agency was only founded in 2014 and launched its first satellite in 2018, making a Mars mission an ambitious leap. The Land’s Hope Orbiter will gather evidence to solve one of Mars’ greatest unsolved mysteries: How does Martian weather work?SN: 7/4/20 & 7/18/20, p. 24)? As the first spaceship to orbit the planet’s equator, Hope offers a new look at how the Martian atmosphere changes daily, seasonally and at different altitudes.
SpaceX doesn’t just send astronauts into orbit. The company has launched hundreds of satellites as part of its Starlink project to deliver high-speed Internet around the globe. Other companies are planning to start similar “mega-constellations”. If everything goes according to the plans of various companies, there will be about 100,000 satellites in low orbit.
“That’s a lot of satellites,” says McDowell. As of August 1, only 2,787 operational satellites doing all kinds of work orbited Earth. Scientists fear that the upcoming satellite flood could spoil the night sky for astronomy by reflecting extra light onto terrestrial telescopes (SN: 28.03.20, p. 24).
By mid-October, SpaceX had already launched more than 900 Starlink satellites. The company tested a dark coating to make the satellites less reflective, but that didn’t help enough. Now SpaceX is launching satellites with small visors to reduce reflectivity, which helps a bit, says McDowell.
The good news is that astronomers and space companies are discussing the problem. At a meeting in the summer, scientists presented simulations of the worst-case scenarios. The effects of these mega-constellations will depend on how many satellites are actually launched and what kind of astronomy you’re considering, says McDowell. Some of the worst effects will be on near-Earth asteroid detection observations.
“We might miss the rock that is going to kill us all because the satellite stripes interfered with the calculation of its orbit,” says McDowell.
One thing that would help is state regulations about the characteristics of satellites that can be launched, McDowell says. Companies “make the right noises when they want to help,” he says, but noises and actions are not the same.
“I think with additional work and attenuation, we’ll get to a point where it’s not fatal to ground-based astronomy, but it’s still a huge impact,” says McDowell. “We may not know the full ramifications until we’re really at it.”