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Last week, SpaceX launched 60 Starlink telecommunication satellites, the first major launch of its ambitious fleet of 12,000 satellites, with the goal of eventually creating high-speed Internet services worldwide.
The launch of the 227-kilogram (500-pound) satellites went off without a hitch, but a spectacular video of the "train" of satellites over the Netherlands – taken by archaeologist and amateur astronomer Marco Langbroek – sparked a discussion about the potential problems this Starlink Fleet could cause in the night sky.
The video below is not what the Starlink satellites will look like when fully deployed, as this video was filmed less than 24 hours after it was released.
According to Space.com, satellites are not bright enough to be visible to the naked eye, and once they have dispersed, they should again be slightly attenuated.
But the naked eye is not all about the needs of astronomers.
Existing satellites are already difficult to process for ground-based telescopes, says astronomer Alan Duffy of Swinburne University, who is also the chief scientist of the Royal Institution of Australia.
"Current satellites are a problem, but astronomers have come up with some clever techniques to remove them," Duffy told ScienceAlert.
Read more:SpaceX launched tonight a rocket carrying 60 Starlink satellites in a global high speed internet system. Watch the rocket take off and deploy its payload live.
"Optical telescopes such as Pan-STARRS automatically mask images from passing satellites, whereas with radio telescopes such as ASKAP in Western Australia, we scan the sky in the frequency ranges between satellite navigation signals as well. brilliant than the GPS, for example. "
According to current data from the United Nations Office for Outer Space Affairs, there are currently 5,162 objects in orbit around the Earth, of which about 2,000 are operational.
As a result, the deployment of a network of 12,000 satellites would be unprecedented. The environment in which we live is constantly filled with radio waves – WiFi, telephone towers and wireless networks emit a lot of radio noise, but satellites are much worse for radio telescopes than for anything terrestrial.
"A complete constellation of Starlink satellites will probably mean the end of Earth-based radio telescopes capable of sweeping the sky in search of pale radio objects," Duffy said.
"The huge benefits of global Internet coverage will outweigh the cost to astronomers, but the loss of the radio sky is a cost to humanity as we lose our collective birthright to see the glow of the Big Bang or the glow of the stars in formation of the Earth. "
Duffy thinks that Starlink's fleet will make these radio frequency interference "inevitable" and suggests that we have to "build a radio telescope on the other side of the moon", immune to the radio noise of the planet.
It seems that SpaceX has not yet completely solved radio astronomy problems.
Last year, Harvey Liszt, astronomer of the US National Radio Astronomy Observatory, wrote to the US Federal Communications Commission (FCC), expressing his concerns about the project.
Read more: Elon Musk has a deadline of 2027 to surround Earth with Starlink high-speed Internet satellites – but the service would work much sooner than that.
According to Liszt, coordination between several national observatories and SpaceX "has been inconclusively stopped around mid-2017 after a preliminary and rather preliminary treatment of radio astronomy concerns and how SpaceX planned to treat them. ".
One of the reasons we do not have a comprehensive SpaceX plan for the 12,000 satellites could be because these first 60 satellites are still considered "test class satellites". In addition, in 2015, industry experts asked if projects such as Starlink could even be profitable.
Despite various concerns, SpaceX has confirmed on Twitter plans for up to six launches in 2019.
With so many satellites, it's not just radio pollution that can become a problem. There is also junk food in the space.
"SpaceX is proposing to add 12,000 new satellites in the low-Earth orbit region, where most of the waste is located, which represents 40% more objects in a few years, unlike the 60 years it takes to accumulate the current mass of space debris. "says Alice Gorman, space archaeologist at Flinders University in Adelaide, Australia.
"We envision a radically different debris environment."
To be fair to SpaceX, they have a space debris mitigation plan that was filed with the FCC in 2017 according to ArsTechnica; The plan indicated how satellites would desorb once they approach "the end of their useful life (about five to seven years) at a much faster rate than that required by international standards."
"[Satellites] will desorb as it moves propulsively into a storage orbit from which they will return to the Earth 's atmosphere approximately one year after the completion of their mission. "
But it is unlikely that it helps if a satellite is hit before it has a chance to escape. And as pointed out the recent alert to the International Space Station, it only takes a small hole to pose a big problem. Even a small debris can hurt a satellite.
"If this system fails, SpaceX predicts that it will take five years for a satellite to reinstate the atmosphere." There is plenty of time for collisions to occur, especially when the density of materials in orbit increases, "Gorman told ScienceAlert.
This type of impact, with so many satellites nearby, could trigger a cascade of uncontrollable collisions known as Kessler syndrome. The scenario proposed by NASA scientist Donald Kessler in 1978 looks pretty much the same: when the amount of objects in the Earth's orbit becomes high enough, a collision could create a cascading effect, create more debris and increase the risk of subsequent collision.
"We often have our eyes on space debris problems, with an estimated at least 40 per cent of missions failing to comply with UN and other guidelines to minimize the amount of new debris created," he said. said Gorman.
"SpaceX has taken all the necessary measures in terms of desorbite and collision avoidance … We will have to see how it will work with so many new satellites."
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