In mid-2016 Russia announced that it was going to make public its database of known objects in orbit around the earth. This would include all its own satellites as well as non-Russian satellites it had located and was tracking. Russia proposed that other nations who put satellites in orbit to do the same and let the UN manage this master database. Russia pointed out that the database it is putting online lists 40 percent more objects than any publically available American database and that this is largely because Russia has more telescopes and radars watching orbital space and has these observers operating from locations all over the largest nation on the planet.
The United States has a classified database of all satellites it knows about, including their status (active, inactive, and when some are about to plunge to earth). The United States did not jump at the opportunity to join this unclassified master database because that would mean revealing satellites that have managed to keep their location secret. The U.S. is more concerned about letting China know where its hidden satellites are. Russia is no longer able, because of shortages of cash and tech, to put up as many satellites as it did during the Cold War. The U.S. sees China as the new threat and has already accused China of putting secret anti-satellite devices in orbit. China and Russia are allies and the U.S. does not trust either of them to keep their promises. Russia is pitching this to the UN as a positive step in policing international agreements to not weaponize space. None of the other nations that can put satellites up trust China either but Russia has nothing to lose and much to gain by making an issue of its proposal in the UN.
Meanwhile there is a need to find, track and report orbital debris as well as satellites. That effort has been going on for decades and actually gets a lot of international cooperation, even though it has long been believed that the major satellite producers (the U.S., China and Russia) have not revealed all they know. Despite that there is a growing need for as complete a debris database as possible to be maintained and made public. For example, in early 2013 Russia reported that one of its satellites was hit and damaged by debris from a Chinese satellite that China had destroyed in a 2007 anti-satellite weapon test. This is only the second time that an active (still operational) satellite was hit by orbital debris. The last time was in 2009, when an American satellite was hit by a dead Russian satellite. Since then owners of active satellites have paid more attention to where all the space junk (debris) is up there and it is more common for active satellites to move out of the way of oncoming concentrations of debris. This uses up precious fuel, which is normally used to maintain a low flying satellite in the proper orbit. When the fuel is gone, so is the ability to move and the usefulness of the satellite.
The 2009 loss was an American Iridium satellite, which supplies satellite phone service and was at an altitude of about 770 kilometers over central Russia. The Iridium satellite was hit by a dead Russian communications satellite (the one ton Cosmos 2251, equipped with a nuclear power supply, launched in 1993). The Russian bird could not be moved, nor could the Iridium (which, while active, was not equipped with thrusters for movement). The Iridium bird was one of sixty, so satellite phone services was not interrupted because of the spare capacity in the system. The collision turned the two satellites into 600 bits of debris.
The last time anything like this happened was in 1991, when a dead satellite ran into debris from another and created more debris. There have been two deliberate collisions since then. In 2007, China launched a "killsat" that maneuvered into the path of a dead Chinese weather satellite and destroyed it. In 2008, the U.S. Navy used one of its Aegis equipped warships to destroy a malfunctioning U.S. spy satellite with an anti-missile missile. Russia and China have since called for such U.S. activity to be outlawed.
Since the late 1950s humans have been putting objects into orbit and there is a rapidly growing collection of junk up there. Currently, over 300,000 dangerous objects 10 mm (.4 inch) in size have been identified. The smallest of these is capable of disabling a satellite, or damaging a spacecraft, mainly because these objects collide at very high speed (9-10 times faster than a bullet) when the two objects are coming from different directions.
There are nearly 22,000 objects 10 centimeters (4 inches) or larger in LEO (low earth orbit) and 500,000 smaller objects that are still large enough to cause damage. All of these can do some catastrophic damage to satellites or spacecraft. There are millions of objects smaller than 10mm, and these are responsible for many satellites failing early because of cumulative damage from getting hit by several of these micro objects. There are over 250 commercial satellites up there, plus nearly as many military ones.
There are a lot of people keeping an eye on this clutter. The U.S. Air Force Space Surveillance Network, which tracks objects 10mm and larger, stopped sharing all of its information in 2004, for national security reasons. The Russian Space Surveillance System is known to use radar to track over 5,000 objects in low orbit. But until recently the Russians have never shared this data completely or regularly. Filling in the gaps are two international organizations, IADC (Inter-Agency Space Debris Coordination Committee) and ISON (International Space Observation Network). IADC is a government operation, whose members include the U.S. NASA and the equivalents in Russia, China, and several other major nations. Like most government organizations, not all data is shared.
ISON is a non-government organization, and they come up with some of the most interesting stuff. ISON comprises 18 scientific institutions, 18 observatories, 25 telescopes, and over a hundred professionals. ISON does not, as far as anyone knows, withhold data because of any national security concerns. This is fairly certain because ISON work is monitored, and complemented, by the efforts of thousands of amateur astronomers and orbital addicts who connect via the Internet and constantly scour the orbital space for new objects and dangerous movements by existing ones.
ISON has already spotted more than 200 larger (over 10mm) objects that have never been reported by any of the government organizations. The Internet based amateurs are often the first to spot a lot of this new activity, mainly because they have more eyeballs, and, in some cases, impressive optical equipment searching the skies.
When someone spots an object headed for a maneuverable satellite, the owner is alerted and the bird is moved. This has happened several times in the last few years. The number of dangerous objects up there increases 10-20 percent a year. That's even with many of them falling into the atmosphere and burning up each year. Apparently, no one was able to predict the collision between Cosmos 2251 and the Iridium bird, nor the recent collision, largely because the high speed of these objects, and slight instability of their orbits, can turn an expected near miss into a direct hit.