| The term "astronaut" derives from the Greek words meaning "space sailor," and refers to all who have been launched as crew members aboard NASA spacecraft bound for orbit and beyond. Since the inception of NASA's human space flight program, we have also maintained the term "astronaut" as the title for those selected to join the NASA corps of astronauts who make "space sailing" their career profession. The term "cosmonaut" refers to those space sailors who are members of the Russian space program. |
NASA uses moon as mirror to watch Venus transit sun.Just like human eyes, the Hubble Space Telescope can't observe the sun directly - so NASA scientists plan to study Venus's solar transit in June by using the moon as a mirror.It's the same way astronomers sample the atmospheres of giant planets outside our solar system as they pass in front of their stars. While we already know the chemical makeup of Venus's atmosphere, and that it shows no signs of life on the planet, the observations will help test whether this technique has a chance of detecting the very faint fingerprints of an Earth-like planet outside our solar system. The astronomers will use the Advanced Camera for Surveys, Wide Field Camera 3 and Space Telescope Imaging Spectrograph to view the transit in a range of wavelengths, from ultraviolet to near-infrared light. During the transit, Hubble will capture images and carry out spectroscopy to try and detect information about the makeup of Venus's atmosphere. Hubble will observe the Moon for seven hours, before, during, and after the transit so the astronomers can compare the data. The team needs this long observation to detect the extremely faint spectral signatures - only 1/100,000th of the sunlight will filter through Venus's atmosphere and be reflected by the moon. It's the last chance this century to see Venus passing in front of the sun, with the next transit due in 2117. |

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