The U.S. believes they have spotted a new Chinese ASAT (anti-satellite) system in orbit. This one, Shijian-17, has a grappling arm that enables the ASAT to maneuver into position and grab another satellite for closer examination or to put it in another orbit that will cause it to plunge earthward and burn up in the atmosphere. China also has high-powered, ground-based lasers that can disable a satellite at the lower end of low orbits for satellites that could not be forced low enough to be drawn into the atmosphere.
This is one of many Chinese ASAT weapons being developed tested and ready for a major wartime use of ASAT weapons that could destroy over a hundred satellites and create a much larger threat to any surviving satellites or space vessels passing through orbital space. This is part of a Chinese plan to carry out a “Pearl Harbor” type surprise attack on American space-based sensors, navigation and communications systems. This would make Chinese surface or air-based attacks more effective.
Russia has also put into orbit highly maneuverable ASATs that can get close enough to another satellite for close examination and possible destruction or disabling using their ground-based NUDOL laser. The Chinese are building on Russian efforts and have the resources to do this on a large scale.
Chinese ASATs like Shijian-17 were not unexpected but China claims Shijian-17 is there for peaceful purposes, to find and destroy orbital debris. China has also developed and put into service powerful arrays of radars and optical systems for spotting and determining the orbit of LEO (low earth orbit) satellites at the same time it was getting easier to develop and build other types of ASAT systems. Some of these systems are not new, just improved. Back in the 1980s the U.S. developed and tested both ASAT missiles (ASM-135) and air-launched satellite launcher rockets (the Pegasus). Back then the U.S. Air Force developed the ASM-135 for knocking down LEO satellites by using a 1.2-ton missile launched from a high-flying jet fighter. This was done in response to news that Russia was developing a similar system. The Russian system relied on killsats (Killer Satellites) and was never that effective. A successful test of ASM-135 was conducted in 1985, but the program was shut down three years later because the Air Force preferred to spend the money elsewhere.
A little later, in the 1990s, a civilian firm (Orbital ATK) developed, tested and built Pegasus air-launched (from a B-52 or modified large airliner) three-stage solid fuel rockets for putting small (up to half a ton) satellites into LEO. The first version of Pegasus weighed 19 tons and the latest one 23 tons. Between 1990 to 2016 Pegasus was used 43 times and failed only 7 percent of the time. Most of the failed launches were early development models. In other words, Pegasus is still in use and the Air Force has admitted that the ASM-135 could resume production and be even more reliable, effective and cheaper because of advances in missile and guidance tech since the 1980s.
Meanwhile there have been losses to space debris, whether it was created intentionally by an ASAT or by accident. 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 ASAT test. This was 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. There was a recent incident of the manned ISS International Space Station) suffering damage from a small undetected piece of debris. Even before the ISS incident 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 when it collided with a dead Russian communications satellite; the one-ton Cosmos 2251. This one-ton satellite was equipped with a nuclear power supply when it was 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 were not interrupted because of the spare capacity in the system. The collision turned the two satellites into 600 bits of debris.
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, even though most of the debris from that satellite soon fell to earth, burning up rather than hitting the ground.
At the same time China was developing even more ambitious ASAT systems. American analysts believe China conducted three tests of ASAT systems by 2013. One test apparently sought to put a KillSat in a high enough (20,000 kilometers) orbit that could threaten the American GPS network. Another ASAT destroyed an old Chinese weather satellite that was about 850 kilometers up. That's at the upper range of where most reconnaissance satellites hang out. In 2016 a second test was conducted but the target satellite was not actually destroyed.
Back in 2008, Russia and China urged the UN to outlaw the development or testing of ASAT systems. The impetus for this was the 2008 destruction of a broken U.S. spy satellite using a ship-based anti-aircraft missile modified to intercept ballistic missiles. What upset China and Russia was that this feat put all their satellites in a low earth orbit (160-2,000 kilometers up) at risk. A Pearl Harbor in space is not as effective if the enemy can quickly retaliate against Chinese satellites.