Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Extreme machine simulates space conditions

07.05.2002


Conditions in space are unlike anything we experience on Earth. Incredible extremes of temperature that can switch in an instant, startling vacuum conditions, not to mention radiation - it`s a tough life for a spacecraft. So it is essential to make sure they are prepared to withstand these conditions before they are launched into this wholly unfriendly environment.



For instance, in a vacuum, heat cannot be conducted as it is here on Earth. A spacecraft that is being heated by the Sun`s rays may, at the same time, be experiencing temperatures far below freezing on the side of its body facing away from the Sun. Similarly, when the spacecraft shifts and moves out of the sunlight altogether, the rapid drop in temperature experienced by the spacecraft would be more dramatic than putting an ice cube into a furnace. These sudden changes in temperature mean that the spacecraft has to be extremely flexible, as well as resilient, in order to cope with the inevitable expansions and contractions it will undergo as it moves in and out of the Sun`s rays.
In order to find out what it is really like out there, most of the European Space Agency`s science spacecraft are carefully loaded into an enormous simulator that is capable of creating the nearest thing to space conditions here on Earth. Looking like a giant tin can 10 metres in diameter, the Large Space Simulator, the largest of its kind in Europe, is used to inflict these extremes on the spacecraft it is testing, in order to check, recheck, and then check again, that it is up to the job.

Preparing the simulator is an extremely delicate task and has to be carried out with the utmost care. "If there is a scratch smaller than a hair`s breadth at a joint in the pipes feeding the simulator, the liquid nitrogen we use to cool the unit would leak out and the vacuum would be lost," says Philippe Sivac, a spacecraft engineer at ESA`s test centre in the Netherlands. "So there is always a moment of suspense when we first switch on."



Liquid nitrogen is perfectly suited to producing the exceptionally cold temperature required to simulate the conditions spacecraft will encounter. It is commonly used in medicine where rapid and extreme cooling is needed to preserve small and delicate items, such as living organs. But in order to simulate the freezing cold conditions of deep space, vast quantities are required. It is delivered twice a day at the test centre in an enormous tanker throughout the testing period. "We need to use 3000 litres an hour to get the temperature down to minus 190ºC, so we get deliveries of 30 000 litres at a time," says Philippe.

At the other extreme, huge and powerful lamps simulate the intensity of the Sun`s rays on the spacecraft using a light beam that is six metres in diameter. This accurately reproduces the spectrum of solar light, generating a light intensity of up to 2000 watts per square metre - similar to turning on 600 household light bulbs in a small bedroom, and temperatures quickly reach more than 130ºC.

When a spacecraft orbiting the Earth moves into an eclipse, where the Earth shields it from the Sun, its temperature will drop dramatically. In the simulator this sudden change is reproduced by turning off the lamps. The testing process has to make sure that every instrument on board the spacecraft stays within the temperature guidelines at which it can still operate, no matter what it is like outside.

Such painstaking testing procedures are necessary milestones in a spacecraft`s journey towards launch into space. Currently, the space simulator is subjecting the INTEGRAL spacecraft to the ordeal that is space - the environment it will be visiting in October 2002 when it enters its orbit around the Earth. There, it will be gathering some of the most energetic radiation that exists: gamma rays from black holes and other sources, such as supernova explosions. At least the scientists know that the spacecraft has a fighting chance against the worst conditions that space can throw at it.

Monica Talevi | alphagalileo

More articles from Physics and Astronomy:

nachricht Ultra-compact phase modulators based on graphene plasmons
27.06.2017 | ICFO-The Institute of Photonic Sciences

nachricht Smooth propagation of spin waves using gold
26.06.2017 | Toyohashi University of Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>