Space debris is a growing problem, so companies are working on ways to mitigate it. A new satellite called ADRAS-J was built and launched to demonstrate how a spacecraft could rendezvous with a piece of space junk, paving the path for future removal. Astroscale Japan Inc, the Japanese company behind the satellite, released a new picture from the mission showing a close image of its target space debris, a discarded Japanese H2A rocket’s upper stage, captured from just a few hundred meters away.
Continue reading “This is an Actual Picture of Space Debris”Watch a Real-Time Map of Starlinks Orbiting Earth
In an effort to enhance the educational outreach of their Starlink constellation, there is an interactive global map of their Starlink internet satellites, which provides live coverage of every satellite in orbit around the Earth. This interactive map and information was produced by Will DePue, who is a an OpenAI programmer and openly states he is not affiliated with SpaceX or Starlink. This interactive map comes as SpaceX continues to launch Starlink satellites into orbit on a near-weekly basis with the goal of providing customers around the world with high-speed internet while specifically targeting rural regions of the globe. In 2022, Starlink officially reached all seven continents after Starlink service became available in Antarctica. Additionally, SpaceX announced in 2023 a partnership with T-Mobile for Starlink to provide mobile coverage, as well.
Continue reading “Watch a Real-Time Map of Starlinks Orbiting Earth”Millions of Satellites Could Have a Profound Effect on the Earth’s Ionosphere
Hardly a day goes by where a story hits the headlines about our abuse of the Earth’s precious environment be that the atmosphere or the oceans, forests or desert. When it comes to the atmosphere we all tend to immediately turn our attention to pollution, to gasses being released and disturbing the delicate balance. Yet a paper recently published points to a new demon, megaconstellations of satellites damaging the ionosphere – the ionised part of the upper atmosphere.
Continue reading “Millions of Satellites Could Have a Profound Effect on the Earth’s Ionosphere”One of the Brightest Stars in the Sky is Actually a Satellite
Back in the 70s, kids used to look up at the summer sky and try to be the first one to shout, “Satellite!” That seems like a relic from the past now, alongside Polaroid cameras and astronauts on the Moon. These days, it’s rare to spend any amount of time looking at the sky without seeing a satellite, or several of them.
A new satellite is emphasizing that fact. It’s a prototype communications satellite with a roughly 700-square-foot antenna, and it’s brighter than most stars.
Continue reading “One of the Brightest Stars in the Sky is Actually a Satellite”What is Low Earth Orbit?
Beginning in the 1950s with the Sputnik, Vostok and Mercury programs, human beings began to “slip the surly bonds of Earth”. And for a time, all of our missions were what is known as Low-Earth Orbit (LEO). Over time, with the Apollo missions and deep space missions involving robotic spacecraft (like the Voyager missions), we began to venture beyond, reaching the Moon and other planets of the Solar System.
But by and large, the vast majority of missions to space over the years – be they crewed or uncrewed – have been to Low-Earth Orbit. It is here that the Earth’s vast array of communications, navigation and military satellites reside. And it is here that the International Space Station (ISS) conducts its operations, which is also where the majority of crewed missions today go. So just what is LEO and why are we so intent on sending things there? Continue reading “What is Low Earth Orbit?”
Artificial Satellites
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Artificial satellites are human-built objects orbiting the Earth and other planets in the Solar System. This is different from the natural satellites, or moons, that orbit planets, dwarf planets and even asteroids. Artificial satellites are used to study the Earth, other planets, to help us communicate, and even to observe the distant Universe. Satellites can even have people in them, like the International Space Station and the Space Shuttle.
The first artificial satellite was the Soviet Sputnik 1 mission, launched in 1957. Since then, dozens of countries have launched satellites, with more than 3,000 currently operating spacecraft going around the Earth. There are estimated to be more than 8,000 pieces of space junk; dead satellites or pieces of debris going around the Earth as well.
Satellites are launched into different orbits depending on their mission. One of the most common ones is geosynchronous orbit. This is where a satellite takes 24 hours to orbit the Earth; the same amount of time it takes the Earth to rotate once on its axis. This keeps the satellite in the same spot over the Earth, allowing for communications and television broadcasts.
Another orbit is low-Earth orbit, where a satellite might only be a few hundred kilometers above the planet. This puts the satellite outside the Earth’s atmosphere, but still close enough that it can image the planet’s surface from space or facilitate communications. This is the altitude that the space shuttle flies at, as well as the Hubble Space Telescope.
Artificial satellites can have a range of missions, including scientific research, weather observation, military support, navigation, Earth imaging, and communications. Some satellites fulfill a single purpose, while others are designed to perform several functions at the same time. Equipment on a satellite is hardened to survive in the radiation and vacuum of space.
Satellites are built by various aerospace companies, like Boeing or Lockheed, and then delivered to a launch facility, such as Cape Canaveral. Launch facilities are located as close as possible to the Earth’s equator, to give an extra velocity kick into space. This allows rockets to use less fuel or launch heavier payloads.
The altitude of a satellite’s orbit defines how long it will stay in orbit. Low orbiting satellites are mostly above the Earth’s atmosphere, but they’re still buffeted by the atmosphere and their orbit eventually decays and they crash back into the atmosphere. Other satellites orbiting in high orbits will likely be there for millions of years.
We’ve written many articles about artificial satellites for Universe Today. Here’s an article about geosynchronous orbit, and here’s an article about orbital speed.
You can get more information about satellites from NASA. Here’s a cool realtime satellite tracking system, and here’s Hubblesite.
We’ve also recorded several episodes of Astronomy Cast about satellites. Here’s a good one, Episode 82: Space Junk.
Source: NASA