TAU (spacecraft)
TAU (Thousand Astronomical Units) was a proposed
Overview
TAU was a proposed
One of the tasks envisioned for TAU would be a flyby of Pluto.[3] A Pluto flyby was achieved in 2015 by the New Frontiers program mission New Horizons.
Some of the instruments proposed for the design included a 1.5-meter telescope for observations and a 1-meter telescope for laser communication with Earth.[4]
After launch it would accelerate to about 106 km/s (about 22.4 AU/year, or ~0.04% the speed of light) over 10 years, using xenon as propellant and a nuclear fission reactor for power.[4]
Description and mission profile[5]
- Payload module (5,000 kg mass including a 10-watt laser transponder+1-meter-aperture laser communications telescope capable of transmitting data at 20 kilobits/second at 1000 AU, and a 1.5 meter astrometric telescope plus other experiments)
- Propulsion module (4,000 kg dry mass including ten 4.45 newton thrust ion propulsion clustered in groups of five and fired paired for two years each. The total specific mass of ion thrusters, power processor units, etc. would be 4 kg/kWe (kilograms per kilowatt electrical power))
- 1-MWe nuclear reactor+shield+radiator (6,000 kg mass or 12.5 kg/kWe specific mass)
The 25,000 kg (gross launch mass including 10,000 kg of
The TAU payload module would have separated from the rest of the spacecraft after ten years of constant thruster firing at a distance of 12 billion km (80 AU)[7] as the xenon propellant tanks would have been depleted. TAU would have reached 200 AU in 15 years after launch, 400 AU in 23 years, 600 AU in 32 years, 800 AU in 41 years and the full 1000 AU in half a century. Even so, it would have traversed less than 0.4% of the 4.3 light years to Alpha Centauri, the nearest star.
See also
- Innovative Interstellar Explorer (NASA 2003)
- Interstellar Probe (NASA 1999)
- Interstellar probe (Generic)
- Cosmic distance ladder
- (87269) 2000 OO67 (has an aphelion over 1000+ AU and orbits the Sun)
- Related to Solar System departure:
- Interstellar travel
- Spacecraft escaping the Solar System (Category)
- Artificial objects escaping the Solar System
- Nuclear power in space
References
- Bibcode:1987STIN...8728490E.
- ^ "Tau - A Mission to a Thousand Astronomical Units" (PDF). Jet Propulsion Laboratory. Archived from the original (PDF) on 2007-09-30.
- ISBN 978-1-4381-0950-3.
- ^ a b "And Now for the Stars". New Scientist. Reed Business Information. 1987. p. 33.
- ISBN 0 7106 0646 X
- ^ "Проект "TAU"".
- ISBN 0 7106 0444 0
External links
- Tau (Thousand Astronomical Unit) Mission in The Encyclopedia of Astrobiology, Astronomy, and Spaceflight.
- Abstract of "TAU -- A MISSION TO A THOUSAND ASTRONOMICAL UNITS" by K. T. Nock of the Jet Propulsion Laboratory.
- Abstract of "Preliminary scientific rationale for a voyage to a thousand astronomical units" by M. I. Etchegaray of the Jet Propulsion Laboratory and the California Institute of Technology.