Low-cost precursor of an interstellar mission. (arXiv:2007.12814v1 [astro-ph.IM])
<a href="http://arxiv.org/find/astro-ph/1/au:+Heller_R/0/1/0/all/0/1">René Heller</a> (1), <a href="http://arxiv.org/find/astro-ph/1/au:+Anglada_Escude_G/0/1/0/all/0/1">Guillem Anglada-Escudé</a> (2,3), <a href="http://arxiv.org/find/astro-ph/1/au:+Hippke_M/0/1/0/all/0/1">Michael Hippke</a> (4,5), <a href="http://arxiv.org/find/astro-ph/1/au:+Kervella_P/0/1/0/all/0/1">Pierre Kervella</a> (6) ((1) Max Planck Institute for Solar System Research, Göttingen (GER), (2) Institut de Ciències de l'Espai, Bellaterra (ESP), (3) Institut d'Estudis Espacials de Catalunya, Barcelona (ESP), (4) Sonneberg Observatory (GER), (5) Visiting Scholar, Breakthrough Listen Group, Astronomy Department, UC Berkeley (USA), (6) LESIA, Observatoire de Paris (FRA))
The solar photon pressure provides a viable source of thrust for spacecraft
in the solar system. Theoretically it could also enable interstellar missions,
but an extremely small mass per cross section area is required to overcome the
solar gravity. We identify aerographite, a synthetic carbon-based foam with a
density of 0.18 kg/m^3 (15,000 times more lightweight than aluminum) as a
versatile material for highly efficient propulsion with sunlight. A hollow
aerographite sphere with a shell thickness eps_shl = 1 mm could go interstellar
upon submission to the solar radiation in interplanetary space. Upon launch at
1 AU from the Sun, an aerographite shell with eps_shl = 0.5 mm arrives at the
orbit of Mars in 60 d and at Pluto’s orbit in 4.3 yr. Release of an
aerographite hollow sphere, whose shell is 1 micrometer thick, at 0.04 AU (the
closest approach of the Parker Solar Probe) results in an escape speed of
nearly 6900 km/s and 185 yr of travel to the distance of our nearest star,
Proxima Centauri. The infrared signature of a meter-sized aerographite sail
could be observed with JWST up to 2 AU from the Sun, beyond the orbit of Mars.
An aerographite hollow sphere with eps_shl = 100 micrometer and a radius of 1 m
(5 m) weighs 230 mg (5.7 g) and has a 2.2 g (55 g) mass margin for interstellar
escape. The payload margin is ten times the mass of the spacecraft, whereas the
payload on chemical interstellar rockets is typically a thousandth of the
weight of the rocket. Simplistic communication would enable studies of the
interplanetary medium and a search for the suspected Planet Nine, and would
serve as a precursor mission to alpha Centauri. We estimate prototype
developments costs of 1 million USD, a price of 1000 USD per sail, and a total
of <10 million USD including launch for a piggyback concept with an
interplanetary mission.
The solar photon pressure provides a viable source of thrust for spacecraft
in the solar system. Theoretically it could also enable interstellar missions,
but an extremely small mass per cross section area is required to overcome the
solar gravity. We identify aerographite, a synthetic carbon-based foam with a
density of 0.18 kg/m^3 (15,000 times more lightweight than aluminum) as a
versatile material for highly efficient propulsion with sunlight. A hollow
aerographite sphere with a shell thickness eps_shl = 1 mm could go interstellar
upon submission to the solar radiation in interplanetary space. Upon launch at
1 AU from the Sun, an aerographite shell with eps_shl = 0.5 mm arrives at the
orbit of Mars in 60 d and at Pluto’s orbit in 4.3 yr. Release of an
aerographite hollow sphere, whose shell is 1 micrometer thick, at 0.04 AU (the
closest approach of the Parker Solar Probe) results in an escape speed of
nearly 6900 km/s and 185 yr of travel to the distance of our nearest star,
Proxima Centauri. The infrared signature of a meter-sized aerographite sail
could be observed with JWST up to 2 AU from the Sun, beyond the orbit of Mars.
An aerographite hollow sphere with eps_shl = 100 micrometer and a radius of 1 m
(5 m) weighs 230 mg (5.7 g) and has a 2.2 g (55 g) mass margin for interstellar
escape. The payload margin is ten times the mass of the spacecraft, whereas the
payload on chemical interstellar rockets is typically a thousandth of the
weight of the rocket. Simplistic communication would enable studies of the
interplanetary medium and a search for the suspected Planet Nine, and would
serve as a precursor mission to alpha Centauri. We estimate prototype
developments costs of 1 million USD, a price of 1000 USD per sail, and a total
of <10 million USD including launch for a piggyback concept with an
interplanetary mission.
http://arxiv.org/icons/sfx.gif
