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The latest figures related to space debris, provided by ESA’s Space Debris Office at ESOC, Darmstadt, Germany. Courtesy of: http://www.esa.int/Our_Activities/Operations/Space_Debris/Space_debris_by_the_numbers

Number of rocket launches since the start of the space age in 1957:
About 5250

Number of satellites these rocket launches have placed into Earth orbit:
About 7500

Number of these still in space:
About 4300

Number of these still functioning:
About 1200

Number of debris objects regularly tracked by the US Space Surveillance Network and maintained in their catalogue:
About 23 000

Estimated number of break-ups, explosions and collision events resulting in fragmentation:
More than 290

Total mass of all space objects in Earth orbit:
About 7500 tonnes

Number of debris objects estimated by statistical models to be in orbit:
29 000 objects >10 cm
750 000 objects from 1 cm to 10 cm
166 million objects from 1 mm to 1 cm

Euroconsult in its report Satellites to be Built & Launched by 2025 estimates that in the period from 2016-2025 there will be 1450 worldwide launches of government and commercial satellites with a mass of 50kg. Added to satellites under 50kg (the micro and nano market), the number of total launches could increase to 9000, a nearly 6 fold increases from the period 2006-2016. This may be an understatement given plans by SpaceX and others (OneWeb) to launch thousands of low orbit satellites to provide internet service at a greater speed (speed of light is 40% faster in space than in fiber) and to rural areas.

Governments presently dominate the market, particularly in Europe, the U.S., Russia, India, China and Japan, but the spread and breadth of launches is accelerating. Most commercial offerings are in low (Low earth orbit- LEO) to mid-orbit (geostationary- GEO) as the focus is on communication and broadcasting. Historically, space debris as a satellite risk exposure has been minimal, but this will be changing. Small satellites kept within 650 kilometers as international guidelines provide usually do not pose a debris issue, as they fall back to earth and burn-up. In higher orbits, this is not the case, and some foreign launches have ignored the guidelines.

NASA believes that there are more than 20,000 pieces of debris larger than a softball orbiting Earth at speeds up to 17,500 mph. It is unlikely those objects will enter Earth’s atmosphere, but the odds that one will strike and damage functioning satellites and other spacecraft are increasing, according to the National Research Council. With increased orbital density, there will be increased risk of satellite damage from debris, that might even cascade.

Because there is no cost-effective way to remove debris, researchers want to better track objects to avoid potential collisions and are beginning to try to track debris and debris content to better design satellites.

Like the Law of the Sea, international space law is weak on enforcement relying on government channels. It also does not address commercial disruption, which given communication commerce from space is problematic. Space law was principally for territory, not for space debris. Industry, rather than governments, may prove more effective in resolving damage to the satellite, but not in legally resolving temporal pollution. Technological advances may be more fruitful if costs can be kept low.