by Prof. Pierre Kervella of Universidad de Chile and Observatoire de Paris.
Edited by James S. Jenkins and Zaira M. Berdiñas
Alpha Centauri and Proxima are located respectively at 4.37 and 4.24 light-years, a bit more than 40,000 billion kilometers. As a consequence, speed is the primary requirement for an in situ exploration. In fact, an incredibly high speed is required. The Breakthrough Starshot initiative aims at launching a miniature spacecraft to Alpha Cen at a velocity of 0.2 times the speed of light (~60.000 km/s) using a powerful laser. The technological challenges to achieve this velocity are considerable, but a conceptual difficulty is that after a multi-decadal flight, the probe will travel a distance equivalent to the diameter of a planet in less than one second. A very short time to obtain accurate scientific measurements, e.g., images and spectra.
Trajectory of a probe from the Sun to Alpha Centauri (AB) and Proxima (C). The coordinates are in the galactic coordinate system expressed in light years. Credits: from Heller, Hippke & Kervella 2017, AJ, in press.
Achieving a gravitationally bound state has numerous advantages for a long-term study of the stellar system and its planets. The Alpha Cen system ...