2017-07-13

Tanzo & Morris - Debris (Original Mix) [FloorFiller Music]





did you know that there are orbiting clouds of, "debris", More than 500,000 pieces of debris, or so called space junk, are tracked as they orbit the Earth. They all travel at speeds, up to 17,500 mph, fast enough for a relatively small piece of orbital debris, to damage a satellite or a spacecraft. Space debris encompasses both natural (meteoroid) and artificial (man-made) particles. Meteoroids are in orbit about the sun, while most artificial debris is in orbit about the Earth. Hence, the latter is more commonly referred to as orbital debris. Orbital debris is any man-made object in orbit about the Earth which no longer serves a useful function. Such debris includes nonfunctional spacecraft, abandoned launch vehicle stages, mission-related debris and fragmentation debris. There are more than 20,000 pieces of debris larger than a softball orbiting the Earth. They travel at speeds up to 17,500 mph, fast enough for a relatively small piece of orbital debris to damage a satellite or a spacecraft. There are 500,000 pieces of debris the size of a marble or larger. There are many millions of pieces of debris that are so small they can’t be tracked.Even tiny paint flecks can damage a spacecraft when travelling, at these velocities. In fact a number of space shuttle windows have been replaced because of damage caused by material that was analysed and shown to be paint flecks.With so much orbital debris, there have been surprisingly few disastrous collisions. In 1996, a French satellite was hit and damaged by debris from a French rocket that had exploded a decade earlier .(energy weapon test),
On Feb. 10, 2009, a defunct Russian satellite collided with and destroyed a functioning U.S. Iridium commercial satellite. The collision added more than 2,000 pieces of trackable debris to the inventory of space junk.
proof of concept test, (anti satellite manoeuvre, with defunct satellites)
China's 2007 anti-satellite test, which used a missile to destroy an old weather satellite, added more than 3,000 pieces to the debris problem.
proof of concept test, (anti satellite test)
Tracking Debris
The Department of Defence maintains a highly accurate satellite catalogue on objects in Earth orbit that are larger than a softball.
NASA and the DoD cooperate and share responsibilities for characterising the satellite (including orbital debris) environment. DoD’s Space Surveillance Network tracks discrete objects as small as 2 inches (5 centimetres) in diameter in low Earth orbit and about 1 yard (1 meter) in geosynchronous orbit. Currently, about 15,000 officially catalogued objects are still in orbit. The total number of tracked objects exceeds 21,000. Using special ground-based sensors and inspections of returned satellite surfaces, NASA statistically determines the extent of the population for objects less than 4 inches (10 centimetres) in diameter.
Collision risks are divided into three categories depending upon size of threat. For objects 4 inches (10 centimetres) and larger, conjunction assessments and collision avoidance manoeuvres are effective in countering objects which can be tracked by the Space Surveillance Network. Objects smaller than this usually are too small to track and too large to shield against. Debris shields can be effective in withstanding impacts of particles smaller than half an inch (1 centimetre).
Planning for and Reacting to Debris
NASA has a set of long-standing guidelines that are used to assess whether the threat of such a close pass is sufficient to warrant evasive action or other precautions to ensure the safety of the crew.
These guidelines essentially draw an imaginary box, known as the pizza box because of its flat, rectangular shape, around the space vehicle. This box is about a mile deep by 30 miles across by 30 miles long (1.5 x 50 x 50 kilometres), with the vehicle in the centre. When predictions indicate that the debris will pass close enough for concern and the quality of the tracking data is deemed sufficiently accurate, Mission Control centres in Houston and Moscow work together to develop a prudent course of action.
Sometimes these encounters are known well in advance and there is time to move the station slightly, known as a debris avoidance manoeuvre to keep the debris outside of the box. Other times, the tracking data isn’t precise enough to warrant such a manoeuvre or the close pass isn’t identified in time to make the manoeuvre. In those cases, the control centres may agree that the best course of action is to move the crew into the Soyuz spacecraft that are used to transport humans to and from the station. This allows enough time to isolate those spaceships from the station by closing hatches in the event of a damaging collision. The crew would be able to leave the station if the collision caused a loss of pressure in the life-supporting module or damaged critical components. The Soyuz act as lifeboats for crew members in the event of an emergency.
Mission Control also has the option of taking additional precautions, such as closing hatches between some of the station’s modules, if the likelihood of a collision is great enough.
Manoeuvring Spacecraft to Avoid Orbital Debris
NASA has a set of long-standing guidelines that are used to assess whether the threat of a close approach of orbital debris to a spacecraft is sufficient to warrant evasive action or precautions to ensure the safety of the crew.
Debris avoidance manoeuvres are planned when the probability of collision from a conjunction reaches limits set in the space shuttle and space station flight rules. If the probability of collision is greater than 1 in 100,000, a manoeuvre will be conducted if it will not result in significant impact to mission objectives. If it is greater than 1 in 10,000, a manoeuvre will be conducted unless it will result in additional risk to the crew.
Debris avoidance manoeuvres are usually small and occur from one to several hours before the time of the conjunction. Debris avoidance manoeuvres with the shuttle can be planned and executed in a matter of hours. Such manoeuvres with the space station require about 30 hours to plan and execute mainly due to the need to use the station’s Russian thrusters, or the propulsion systems on one of the docked Russian or European spacecraft.
Several collision avoidance manoeuvres, with the shuttle and the station have been conducted during the past 10 years.
NASA implemented the conjunction assessment and collision avoidance process for human spaceflight beginning with shuttle mission STS-26 in 1988. Before launch of the first element of the International Space Station in 1998, NASA and DoD jointly developed and implemented a more sophisticated and higher fidelity conjunction assessment process for human spaceflight missions.
In 2005, NASA implemented a similar process for selected robotic assets such as the Earth Observation System satellites in low Earth orbit and Tracking and Data Relay Satellite System in geosynchronous orbit.
In 2007, NASA extended the conjunction assessment process to all NASA manoeuvrable satellites within low Earth orbit and within 124 miles (200 milometers) of geosynchronous orbit.
DoD’s Joint Space Operations Center (JSpOC) is responsible for performing conjunction assessments for all designated NASA space assets in accordance with an established schedule (every eight hours for human spaceflight vehicles and daily Monday through Friday for robotic vehicles). JSpOC notifies NASA (Johnson Space Center for human spaceflight and Goddard Space Flight Center for robotic missions) of conjunctions which meet established criteria. the following are active satellites


Total number of operating satellites: 1,459
United States: 593Russia: 135China: 192Other: 539
LEO: 803MEO: 96Elliptical: 38GEO: 522
Total number of US satellites: 593
Civil: 10Commercial: 297Government: 136Military: 150
and According to CelesTrak there are 2,691 inactive satellites in orbit. 1,490 satellites are active for a total of 4,181. in 2016 and they were the unclassified variety, and then theres all the other stuff, there is a swam of debris, and the chances of not seeing any of this stuff on the nasa live feed's, is practically impossible as, standardz, hahahahahaha, :) #edio

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