On February 17, 2020, SpaceX launched their Falcon 9 rocket carrying 60 new Starlink satellites from Cape Canaveral Air Force Station, Florida, just 63 days after its previous flight. Although this latest batch of high-speed internet satellites were successfully placed into orbit, the same cannot be said of the rocket booster.
Instead of landing back on SpaceX’s autonomous drone ship called “Of Course I Still Love You”, it made a “soft landing” in the water next to the ship. Had the landing been successful, this would have been a milestone of 50 booster recoveries for SpaceX. However, the company remained hopeful that the equipment remained in one piece.
The cause for the failure is not immediately clear, although some reports suggest a change in orbit for the satellites made the landing more challenging. A 24-hour delay to the fourth launch of this booster, due to a problem with a valve component on the rocket’s second stage, has not been linked to the landing failure of the rocket’s first stage.
Following on from previous missions, SpaceX’s launch of its fifth large batch of satellites brings their current orbiting total to around 300. But this is only the beginning. The system of small broadband satellites in medium and low earth orbit, called the Starlink constellation, is planned to exceed around 42,000 satellites in total, providing broadband internet everywhere on Earth.
SpaceX is not the only company set to enter the future internet space market. London-based startup OneWeb wants to create a constellation of 650 satellites. After a successful launch earlier this month of 34 of those, the company say they are on track to provide global coverage to customers in 2021.Yet, SpaceX’s ability to launch its own rockets means that its growing constellation may even provide limited broadband service as soon as this year.
However, this all comes at a cost, which the astronomy community is becoming increasingly concerned about.
In a paper titled “Concerns about ground based astronomical observations: A Step To Safeguard The Astronomical Sky”, three astronomers from the INAF-Osservatorio Astronomico di Roma have presented their criticisms of satellite constellations.
“With the huge amount of about 50,000 new artificial satellites for telecommunications planned to be launched in Medium and Low Earth Orbit, the mean density of artificial objects will be of >1 satellite for square sky degree; this will inevitably harm professional astronomical images,” the authors wrote.
The trails left behind in images could prove dangerous, the authors warned, as the movements of near Earth objects (NEOs) could be obscured. Images of the night sky will also look different, as the expected brightness of the Starlink satellites will mean only 172 stars are brighter.
Observations in other wavelengths, such as radio, are also of concern as radio-astronomy detectors are already said to be “saturated by the ubiquitous irradiation of satellites communication from Space stations as well as from the ground.”
Others in the astronomy community, such as the International Astronomical Union, Royal Astronomical Society, and the American Astronomical Society have also issued statements voicing their concerns about satellite constellations. They hope to work with SpaceX, and other companies, to help minimize the impact of the satellites on astronomy.