Interstellar Probe (1999)
Interstellar Probe is the name of a proposed NASA space probe intended to travel out 200 AU in 15 years, studied in 1999.[1] This 1999 study by JPL is noted for its 200-meter 1g/m2 solar sail as a propulsion method combined with a 0.25 AU flyby of the Sun to achieve higher solar pressure after which the sail is jettisoned at 5 AU distance from the Sun.[2] Solar sails work by converting the energy in light into the momentum of spacecraft, thus propelling the spacecraft.[3] Felix Tisserand noted the effect of light pressure on comet tails in the 1800s.[3] Note that this is talking about actual electromagnetic light, not the particles in the solar wind.
It proposed using a solar sail to accelerate a spacecraft to reach the interstellar medium, and was designed by the NASA Jet Propulsion Laboratory as a study. It was planned to reach as far as 200 AU within 10 years at a speed of 14 AU/year (about 70 km/s, and function up to 400+ AU.[1] A critical technology for the mission is a large 1 g/m2 solar sail.[1] The probe itself hoped to use an advanced RTG for electrical power, Ka-band radio for communication with Earth, Delta 2 for Earth launch, and a 25 kg instrument package using 20 watts.[1]
This great journey requires advanced propulsion, and the 200-kg Interstellar Probe is designed to use a 200-m radius solar sail to achieve a velocity of 14 AU/yr. After exiting the heliosphere within a decade of launch, it will be capable of continuing on to ~400 AU. Interstellar Probe will serve as the first step in a more ambitious program to explore the outer solar system and nearby galactic neighborhood.
In the following years there were additional studies, including the Innovative Interstellar Explorer (published 2003), which focused on a design using RTGs powering an ion engine rather than a solar sail. Another project in this field for advanced spaceflight during this period was the Breakthrough Propulsion Physics Program which ran from 1996 through 2002.
Later examples of solar sail propelled spacecraft include IKAROS, Nanosail-D2, and Lightsail.[5] Near-Earth Asteroid Scout is a planned light sail-propelled mission.[6] For comparison, the lightsail spacecraft uses a sail 5 micron in thickness, whereas they predict a sail with 1 micron thickness would be needed for interstellar travel.[3]
Objectives
Historical view of region
See also
- Innovative Interstellar Explorer
- Interstellar probe (generic)
- TAU (spacecraft) (1980s era interstellar precursor and astrometry probe)
- Stardust (spacecraft) (Believed to have collected some interstellar micro-dust)
- Interstellar Boundary Explorer (Space observatory that detects neutral atoms from beyond)
- Magsail
References
- 1 2 3 4 "Interstellar Probe". Interstellar.jpl.nasa.gov. 2002-02-05. Retrieved 2010-10-22.
- ↑ Exploration of the Outer Heliosphere and the Local Interstellar Medium: A Workshop Report (2004) PAGE 31 (about half-way down)
- 1 2 3 Propelled by light: the promise and perils of solar sailing
- ↑ NASA IP
- ↑
- ↑