The internet in space
Two British microsatellites test new standards and radiation-protected microprocessors
Actually, the Ariane had already started at a clock at the night GMT in French-Guayana, because of a technical defect, the start was postponed by 24 hours. In addition to other satellites, there are two identical microsatellites of the British Defense Evaluation and Research Agency (Dera) on board, which should test the possibility of internet connections in space for the first time.
With the microsatellites STRV1C and STRV1D, 25 different experiments with the hardware and 5 with software are carried out under the hard conditions of space. For this purpose, the satellites are brought into a geosynchronous elliptical orbit, on which they circle the earth at a distance between 600 and 39000 kilometers. Oberdies are exposed to a high radiation intensity four times a day when they pass the Van Allen Gurtel. During their lifespan of one year, the two satellites are exposed to a 10 times higher radiation, such as satellites on low and geosynchronous orbits is usually the case. Radiation can damage the electronics or generation of solar power severity.
On the satellites are also sensors for exploring the "Space weather". They detect the radiation, the atomic oxygen, the cosmic dust and micrometeorites (whereby space mulling is to be distinguished by natural micrometeorites), anomalies in the ionosphere or electrostatic charges. The individual oxygen atoms are particularly aggressive and could, if they are solar sail and other surfaces, be responsible for damaging harmful harms that are the cause of the limited lifespan of satellites. But since it is not known how many of these oxygen atoms are present at all, the satellites can provide important data here. On surfaces of zinc oxide, the oxygen atoms should impact. When the surface is saturated, it is heated to 80 degrees Celsius, thereby evaporating the oxygen.
For the first time, satellites are supplied with a lithium ion battery. However, a premiere, however, are the tests for an internet in space. On board the satellites are special, protected against the radiation SPARC microprocessors of Sun. The components were in one "High-Z"-Material included, which consists of atoms with a high number of protons. You should stop the radiation better. In a satellite, the microprocessor is deep inside, in the other very double to compare their performance and sensitivity.
The DERA is tested a safe, captive communication link, but also new protocols and standards for internet connections developed by DERA together with NASA and the US Department of Defense as part of the SPACE Communications Protocol Standards (SCPS) initiative. Interestingly, an internet connection could not only be on the Mars not only for art missions, but also for the online control of satellites. "One day one will enter the credit card information online and give the satellite the command to make a picture of them", says Nigel Wells from Dera. "We test new hardware and software at the same time." The computers on board can also be re-programmed by the ground, regularly download data via the Internet connection.
The Internet in space is not just a vision that persecutes about Vinton Cerf, but also a concern of NASA. Between the 1. and 3. November was carried out by the Glenn Research Center a test to check how to control the Internet from the ground from machines in space. "We have been controlled more than 30 years of things in space from the ground, but in contrast to this project of NASA tries to exploit the capacity of the terrestrial Internet and to put them in space", explains Phillip Paulsen, the project manager for the internet in space.
During the test, various places on Earth were sent to a simulated spacecraft in the Johnson Space Center, in which a special control center for the processing and hedging of communication between the ground station and space has been set up. From this control center, the data first went to a NASA satellite and then came to the simulated spacecraft. Simple commands were made: creating a vacuum in a fabbing and turning on or off of light.
There should also be normal conditions for missions, ie what happens, for example, "If several scientists want to have access to their experiment simultaneously or if a user who has priority, wants to log in, if someone else blocks the bandwidth. The list of problems is endless", says Paulsen. The next experiment is to be carried out once with a real spacecraft, perhaps with the international space station, but that will take a while: "At the moment there is no money for that."