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We are burying the Earth in a dead satellite shell that is inaccessible.



Sputnik’s successful launch in 1957 marks a milestone in human history, marking the first time a man-made object has orbited Earth. But we don’t quite understand SNAFU in space where we are so entangled with the advent of satellite technology.In the past 64 years, our planet’s night sky is becoming more and more crowded.Today, more than 3,000 satellites orbit the Earth and count on space debris. Millions of pieces are joined, such as fragments of disassembled satellites, discarded rockets and spacecraft colored shards.NASA estimates that there are 6,000 tons of debris in low Earth orbit alone.

This orbital garbage is not only But creates a navigational hazard for astronauts only But also reflects sunlight down to the water surface, disrupting ground-based telescope observations. A study recently accepted by Monthly Notices of the Royal Astronomical Society: Letter Point out that nowhere on Earth is free of light pollution caused by overhead debris and satellites. What’s more, the researchers expect the amount of orbital debris to increase in order of size over the next decade due to large constellations of small satellites that light the internet, such as SpaceX’s Starlink program.

“Astronomers and night sky viewers must anticipate a future where the Earth’s low orbit population will contain tens of thousands of relatively large satellites,” said Jonathan McDowell of the Harvard Center for Astrophysics. Smithsonian warned in the 2020 study, “The impact will be significant for certain observations, some observatories, and at certain times of the year.”

Until a few years ago, humanity has launched fewer than 10,000 objects into orbit since the beginning of the space age. However, with the advent of low-cost commercial launch technology, the cost per pound of launch dropped from $ 24,800 during the shuttle era to just $ 1,240 today, the rate at which we put satellites into orbit was set. It increases exponentially.

In total, more than 18,000 satellites are expected to launch to LEO by 2025 – about ten times the total number of satellites in use. In 2018, SpaceX alone received permission from the US government to send 12,000 Starlinks to. Orbit Amazon’s Kuiper project will be allowed to launch 3,236 of its own satellites over the next few years. Both programs attempt to create an orbit network in Low Earth Orbit that can provide high-bandwidth, low-latency internet connections that can be accessed from anywhere on Earth. Even if their intentions are high But the unintended consequences of loading large numbers of spacecraft into our skies may change our view of the surrounding solar system.

Starlink light pollution

Starlink light pollution

“If 100,000 or more LEOsats were introduced by many companies and governments, no combination would have been avoided to avoid the impact of satellite routes on the science program of the NIR Astronomical Facility. “Today and planned optical,” noted the report from the American Astronomical Society.

For example, when the first 360 Starlinks were released in May of 2019, their presence in the night sky was immediately noticeable. Their highly reflective design makes each of the smaller satellites about 99 percent brighter than the surrounding objects in the past five months, requiring up to 550 km. This effect is particularly pronounced at sunrise and It falls when the sun’s rays are reflected off the satellite’s solar panels. SpaceX’s attempt to reduce light reflection using The “cure for darkness” in early 2020 proved to be partially successful.

“We detected approximately 55 percent lower reflectance of DarkSat compared to other Starlink satellites,” said Jeremy Tregloan-Reed. From the University of Antofagasta of Chile, said in the 2020 study.

The brightness of celestial bodies is measured according to the star’s magnitude scale, that is, the brighter the object, the larger and more negative the corresponding ranking. For example, the Sun is rated at -26.7 magnitude, while the North Star is rated at +2. Any object with a rating above +6 is effectively invisible to the human eye, although the telescope. Observations and other sensitive observation systems were able to see faint objects up to +8, according to the Treglon-Reed study, the Starlink-treated satellite was +5.33 at working altitude, compared to +6.21 for Untreated satellites

Better but not good enough, Treglon-Reed told me. Forbes Last March, “it was too bright,” he said. The idea is to pass these numbers to policy makers. [and astronomical societies] Negotiating with SpaceX [and mega constellation companies] And try to keep improving this “

The overall impact of these satellites will depend on a number of factors, including the type of telescope used, the time of day and season of observation, and the height of the satellite constellations. Wide area survey both in the visible and infrared spectrum (As one provided by the Veracirubin Observatory in Chile) is particularly vulnerable to this interference, as are observations at dusk. And while the LEO orbiting constellations generally darken as they pass through the Earth’s shadow, the constellations in the orbiting geosynchronous distances of 750 miles or more.For example, the short-lived OneWeb program “Visible all night in summer and is a significant fraction of the night. During winter, fall and spring, and it will have a negative impact on most observation programs, ”according to the AAS.

“High altitude satellites have to actually reflect less light than satellites with inherently lower altitudes to be comparable. [in professional detectors]This is due to two factors: orbital speed. (Lower height satellites move faster, so it takes less time per pixel) and focus (lower height satellites are less in focus, so the streak is wider. But has a lower maximum brightness “University of Washington astronomer Dr. Meredith Rawls said. Forbes.

In response to the growing issue, astronomers from around the world as part of the National Science Foundation’s SATCON-1 workshop last July compiled a list of potential corrective actions and policies. These include limiting the constellations to a maximum altitude of 550 – 600 km, assigning each satellite a stellar size of +7 and above, and sharing orbital information about these constellations with the research community for Allowing astronomers to avoid those areas in the sky

“SpaceX demonstrated that operators can reduce sunlight reflection through satellite orientation, sun protection and surface darkening,” found in the SATCON-1 workshop. It has higher accuracy regarding the projected position of each satellite. (Or ephemeride) may help to avoid pointing and muting mid-range satellites. Alternatively, operators can design their satellites to be cleared at the end of their lifespan, just as Starlink satellites do, or they can launch fewer constellations in general. Whether local or international regulators actually adopt these recommendations, it remains to be seen.

But even if satellite operators have been able to reduce the brightness of their constellations, But we still have to face increasingly dense orbits of broken satellites and overhead space junk. NASA’s Orbiting Space Debris Office estimates that half a million pieces of marble debris are around the LEO at 22,300 mph – fast enough to destroy even the ISS-reinforced windows when affected – and a lot. Up to 100 million pieces with dimensions of millimeters or less.

NASA became the first national space agency to develop comprehensive space junk relief plans in 1995.These guidelines were later modified by the Inter-Space Agency Coordinating Committee. The US government also established Orbital Debris Mitigation Standard Practices (ODMSP) in 2001 with a new effort to “restrict debris mitigation” from the Inter-Agency Space Debris Coordination Committee (IADC) in 10 countries. Generate new long-life waste by controlling debris released during normal operations, reducing waste caused by accidental blasting. Choosing a safe flight profile and operational configuration to reduce accidental collisions and the removal of post-mission space structures. ”The Department of Defense also operates the Space Surveillance Network, which is responsible for listing and disposing of space structures. Tracks objects between 0.12 and 4 inches in diameter using a combination of telescopes, ground imaging and radar.

This debris tracking is just the first step. Several space agencies are actively developing systems to capture and dispose of orbital debris. For example, JAXA is considering a 2,300-yard “AC harness” that, when put into operation, will free up the debris that is sent. Passed back to the planet, where it will burn during its return to the atmosphere in 2018, a group led by the UK’s Surrey Space Center successfully demonstrated the RemoveDebris device, which is basically A large space net designed to capture dead satellites and gaps up to 10 meters long.

claw

claw

By 2025, the ESA hopes to launch a ClearSpace-1 mission in which a four-pronged device will try to snatch space debris like a huge claw game prize, then dispose of itself and dump the bounty in Earth’s atmosphere.

“Space debris is a global problem as it affects every country,” said Airbus mission systems engineer Sander Hall. CNN In 2018, “Each piece of space debris belongs to the original operator and the orbital debris is not explicitly stated in current international law. It takes an international effort to claim ownership of scrap and help secure disposal financing. ”


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