This week marks the 40th anniversary of Britain as a spacefaring nation. On the 28th of October 1971, the UK launched Prospero - a science and technology demonstration satellite - on top of a Black Arrow rocket at Woomera, Australia. This made the UK the 6th nation to demonstrate a working orbital launch capability.

In celebration of this anniversary, space scientists at UCL are attempting to re-establish contact with Prospero and UK space surveillance company Space Insight has captured a new image of the satellite.

This new image was taken just a month after Space Insight celebrated an anniversary of its own - 5 years of tracking objects like Prospero with their space surveillance sensor Starbrook.

The Starbrook image shows Prospero streaking at 27,000 kph (17,000 mph) across the constellation of Pegasus, in a near-polar orbit which varies in height from 500 to 1300 km (300 to 700 miles).

Since initial development five years ago, Space Insight's Starbrook sensors have played a key part in the UK's contribution to European and international space surveillance programmes and initiatives, including ESA's first co-ordinated space tracking campaign.

The UK Space Agency uses the company to provide a wide range of scientific and technical support.

Staff from the Agency and Space Insight are members of the UK delegation to the Inter-Agency Debris Committee, providing support to, and analysis of, technology and strategy options for the surveillance of space, contributing to observation campaigns and predicting satellite re-entry events.

During 1971, when Prospero was launched aboard the UK-developed and built Black Arrow rocket, there were just 3000 objects orbiting the Earth, owned by just a dozen countries.

Many of the satellites, like Prospero, were performing experiments to investigate the effects of the space environment, about which little was known at the time.

It would be another seven years before Don Kessler and Burton Cour-Palais would publish their seminal paper, 'Collision Frequency of Artificial Satellites: The Creation of a Debris Belt', in which they foresaw the rise of the space debris problem.

At that time, with just a few hundred satellites in Earth orbit, it was relatively straightforward and viable to track each one individually using radar or telescope. Today, satellites and debris crowd all Earth orbits. Nearly 40,000 objects overall have been tracked in orbit, with many millions of mm-sized debris estimated.

Over 60 countries and international organisations own satellites, and there are more than a thousand operational satellites in orbit. Many service-based aspects of our daily lives are satellite dependent.

Professor Richard Crowther, Chief Engineer at the UK Space Agency and expert on Near Earth Objects (NEOs) said, "Space surveillance systems like Starbrook are vital in this age of growing space technology.

We're very proud to have such a sophisticated system here in the UK. Starbrook carries on the innovative tradition of British space-related engineering of which Prospero was an earlier pioneer."

While radar techniques are effective at surveying the lower orbits, the high Earth orbits are usually monitored by optical sensors.

With Starbrook, Space Insight reinvigorated the use of optical sensors with wide fields of view, common for satellite observations at the time of Prospero's launch, by applying wide-field techniques to the survey of the high Earth orbits.

Starbrook monitors objects in high Earth orbit as part of the UK's commitment to promoting safe and secure access to space (e.g. monitoring compliance with the Outer Space Treaties).

The Starbrook sensor uses highly sensitive digital imaging technology and wide field of view optics to deliver rapid surveying capability for space surveillance.

Within Europe, it is one of the most productive optical sensors in terms of the numbers of objects monitored per night.