IT'S like a plot lifted straight from the pages of an Ian Fleming James Bond novel – the eccentric billionaire sending a rocket with a mystery payload into orbit. However, SpaceX, the space exploration company whose stated aim is to colonise Mars and which is headed up by super-rich entrepreneur Elon Musk, is doing just that.

And while SpaceX and Musk, are no strangers to publicity, mystery surrounds the US company's latest launch – enigmatically codenamed Zuma and designated simply "government".

The rocket launch, which was a last-minute addition to SpaceX's plans, is a partnership between Musk’s space transport company and Northrop Grumman, a US firm described on the firm's website as a “global security company”.

There is little detail about the mission other than it is carrying a "Low Earth Orbit (LEO) satellite", and the internet is rife with speculation about the expedition's objectives. It is unusual for there to be such secrecy. SpaceX regularly provides updates on its missions on the company's website. The SpaceX website boasts that it has 70 future missions planned. “Our launch manifest is populated by a diverse customer base, including space station resupply missions, commercial satellite launch missions, and US government science and national security missions,” it states.

However, there is no mention of Zuma.

Satellites launched in mysterious circumstances in 2009 and 2014 were used for gathering intelligence for military operations in the Middle East, according to documents leaked by whistle-blower Edward Snowden, a former CIA systems analyst.

The Falcon 9 rocket that will carry the satellite is expected to launch from Kennedy Space Centre in Florida on November 15 before returning to Cape Canaveral when the payload is delivered.

Virginia-based defence contractor Northrop Grumman has a commercial launch contract with SpaceX for a low-earth orbit satellite. Low-earth orbit is an altitude of less than 1,200 miles and is the preferred distance for satellites because it is close enough to provide a clear view of the planet’s surface.

Northrop Grumman told US media it had selected Falcon 9 for Zuma and described the project as a “government mission”.

Lon Rains, communications director at Northrop Grumman's Space Systems Division, said: “The US government assigned Northrop Grumman the responsibility of acquiring launch services for this mission. We have procured the Falcon 9 launch service from SpaceX. This event represents a cost-effective approach to space access for government missions.”

Northrop Grumman Corporation’s revenue in 2016 was almost £19 billion, up 4.2 per cent on 2015. The company's Aerospace Systems segment reported the fastest growth in sales, which amounted to around £8 billion.

This was achieved in part because of Northrop Grumman's involvement in the production of US aircraft including the E-2D Hawkeye and F-35 Lightning II, both of which were delivered in higher quantities in 2016.

SpaceX is an American aerospace manufacturer and space transport services company founded in 2002 by Musk.

The firm’s mission is “to enable humans to become a spacefaring civilisation and a multi-planet species by building a self-sustaining city on Mars,” according to its website.

In 2008, SpaceX’s Falcon 1 became the first privately developed liquid-fuel launch vehicle to orbit the Earth. Nasa later handed SpaceX contracts to carry cargo and crew to the International Space Station (ISS).

SpaceX was the first commercial provider to launch and recover a spacecraft from orbit, attach a commercial spacecraft to the ISS and land an orbital-class rocket booster, its website boasts.

Founder Musk is also CEO of Tesla, which makes electric cars, and chairman of OpenAI, a research company working to build artificial intelligence.

SpaceX did not respond to the Sunday Herald’s request for comment on the Zuma mission.

Thousands of artificial satellites have been put into Earth’s orbit since the launch of Sputnik 1 by the Soviet Union on October 4 1957 – a move which triggered the space race.

From our planet’s surface space can look like a void but there are around 1,700 operational man-made satellites up there, according to data collected by experts at the Union of Concerned Scientists (UCS).

There are also an estimated 21,000 natural satellites - pieces of space junk larger than 10cm across - whirling around at 17,000 mph, as well as 500,000 pieces of debris below ten centimetres in diameter.

UCS statistics show the United States has 803 artificial satellites in orbit. They are categorised as 476 commercial satellites, 159 military, 150 government and 18 civil.

Other big players in space are China with 204 satellites in orbit, Russia with 142 and a further 589 satellites are classed as “other”.

Since 1962, the United Nations has maintained a Register of Objects Launched into Outer Space which establishes liability for space objects.

The Convention on Registration of Objects Launched into Outer Space was formulated in 1976 and compelled states to establish their own national registries and provide information on their space objects to the Secretary-General for inclusion in the United Nations Register.

The United Nations Office for Outer Space Affairs (UNOOSA) maintains the register and it is now estimated that 92 per cent of all satellites, probes, landers, manned spacecraft and space station flight elements launched into Earth’s orbit or beyond have been registered.

As for the other eight per cent? Well… the truth is out there.

Satellites classed as military are not weaponised but instead observe the surface of the planet to assist operations.

In the 1980s US President Ronald Reagan famously unveiled plans to intercept nuclear missiles as they travelled through space in a programme which became known as Star Wars.

However, the Strategic Defense Initiative (SDI) proved to be pie in the sky and research programmes were cancelled by Reagan’s successors.

Current military satellites are used to spy on enemies to detect missile launches and provide intelligence about weapons development and troop deployment.

The UK’s military satellite programme is known as Skynet and new contract to replace existing technology was awarded to Airbus in July.

A spokesman for the Ministry of Defence said in July: “The MoD intends to award Airbus Defence and Space the single source contract for the manufacture, assembly, integration, test and launch of a Skynet 6A geostationary military communications satellite. This will secure delivery of a sovereign and secure capability for the UK.”

The new satellite is expected to be operational by mid-2025, when the MoD’s Skynet 5 constellation approaches the end of its useful life.