from the say-hi-to-Vir-Cotto-for-me dept.
In 2069, if all goes according to plan, NASA could launch a spacecraft bound to escape our solar system and visit our next-door neighbors in space, the three-star Alpha Centauri system, according to a mission concept presented last week at the annual conference of the American Geophysical Union and reported by New Scientist. The mission, which is pegged to the 100th anniversary of the moon landing, would also involve traveling at one-tenth the speed of light.
Last year, Representative John Culberson called for NASA to launch a 2069 mission to Alpha Centauri, but it was never included in any bill.
Meanwhile, researchers have analyzed spectrographic data for the Alpha Centauri system and found that small, rocky exoplanets are almost certainly undiscovered due to current detection limits:
The researchers set up a grid system for the Alpha Centauri system and asked, based on the spectrographic analysis, "If there was a small, rocky planet in the habitable zone, would we have been able to detect it?" Often, the answer came back: "No."
Zhao, the study's first author, determined that for Alpha Centauri A, there might still be orbiting planets that are smaller than 50 Earth masses. For Alpha Centauri B there might be orbiting planets than are smaller than 8 Earth masses; for Proxima Centauri, there might be orbiting planets that are less than one-half of Earth's mass.
In addition, the study eliminated the possibility of a number of larger planets. Zhao said this takes away the possibility of Jupiter-sized planets causing asteroids that might hit or change the orbits of smaller, Earth-like planets.
(For comparison, Saturn is ~95 Earth masses, Neptune is ~17, Uranus is ~14.5, and Mars is ~0.1.)