NASA Begins Tests of E-Sail Technology Using Solar Wind to Travel to the Edge of the Solar System

Deep space exploration requires advanced technological systems for long haul flights. Aside from that, there should also be an unlimited supply of fuel to gas the trip up. But NASA is looking at a more sustainable source of energy for its future flights, by using HERTS Electric sail or E-sail, spacecrafts run by solar wind.

NASA's Marshall Space Flight Center teams are testing the technology to be used for the possible test flight of the Heliopost Electrostatic Transit System (HERTS) or the E-sail system. It is designed to send spacecraft to the edge of the solar system faster and by using renewable energy as its fuel. It will cut the travel time to reach the edge of the Earth by more than half. The Voyager took 35 years to reach the edge of the Solar System, while the E-sail technology will only take 10 years to send a spacecraft to the edge.

HERTS E-sail will be composed of 10 to 20 positively charge tethers which will harvest the solar wind continuously released by the Sun. It will propel and charge the spacecraft.

"The sun releases protons and electrons into the solar wind at very high speeds -- 400 to 750 kilometers per second," said Bruce Wiegmann an engineer in Marshall's Office and the principal investigator for the HERTS E-Sail.

In his proposal for HERTS, Weigmann argued that the main problem with Voyager is the propulsion. That's just one of the reasons why it took the Voyager 35 years to reach to edge of the Solar System. HERTS was designed with the issue in mind.

"It is unique in that it uses momentum exchange from naturally occurring solar wind protons to propel a spacecraft within the heliosphere. The propulsion system consists of an array of electrically biased wires that extend outward 10 to 30 km from a rotating spacecraft" said Weigmann.

The spinning HERTS E-sail spacecraft with 30 kilometer long tethers are being tested inside the High Intensity Solar Environment Test system. Scientists are looking at how the positively charged tethers will react to protons and electrons in the solar wind. Heliophysics is a branch of science which should be explored by NASA to help them in future space exploration because it might help them in finding ways to travel faster in outer space.

"As the team studied this concept, it became clear that the design is flexible and adaptable...Mission and vehicle designers can trade off wire length, number of wires and voltage levels to fit their needs -- inner planetary, outer planetary or heliopause. The E-Sail is very scalable" said Wiegmann.