ELECTRO DYNAMIC TETHER

What is an ELECTRO DYNAMIC TETHER?

Tether means rope or chain used to fasten animals. In the case of space this tether finds application for connecting two space crafts. So tether is a term which needs key relevance that finds application even in space field. Physically a tether is a long flexible cable that connects two masses. When the cable is electrically conductive it is called as electro dynamic tether.

In the early 20th century Giuseppe Colombo came up with an idea of connecting two space crafts by means of some flexible cables. It also needed to be electrically conductive. So as a step forward to this idea NASA launched a shuttle to deploy a satellite on a tether to study the electromagnetic effects of a conducting tether as it passes through Earth’s magnetic fields ad a current was produced in the tether as it passes earth’s magnetic field, acting as an electric generator. This was the actual origin of electro dynamic tether.

There are mainly three types of electro dynamic tether employed systems available depending on the advantages.

1. Electro dynamic tether systems- In this type two heavy masses are separated by means a long flexible extensive electrically conductive cable. This can perform various functions in space craft.
2. In low earth orbit tether can provide electrical power and positioning capability for satellites and space crafts.
3. In the case of long term mission tethers could drastically reduce the amount of fuel needed.

Now tethers are made of electrically conducting materials like aluminium or copper. This provides additional advantages to the tethers. An electro dynamic tether is a device use to convert orbital energy to electrical energy and it works on the principle of electro magnetic induction. This can be used for power generation. Tethers found applications in orbit raising, lowering and debris removal. Another application of tether is artificial gravity inside space crafts.