mercredi 13 avril 2016, par Ivan Linscott (Stanford University)
Lundi 18 avril 2016 à 16h00 , Lieu : Salle de conférence du bâtiment 17
The instruments on board the New Horizons spacecraft, measured key characteristics of Pluto and Charon during the July 14, 2015, flyby. The data collected has beentransmitted to Earth since the encounter a process thatwill continue for the rest of 2016. High resolution images have been obtained along with spatially resolved spectroscopy in the infrared and ultraviolet revealing a world of extraordinary character. Additionally, during flyby the Radio Science Experiment (REX), in the NH X-band radio transceiver, recorded powerful uplink transmissions from Earth stations, as well a broadband radiometric power from the surface of Pluto and Charon. The REX recording of the uplinks produced a precise measurement of the surface pressure, the temperature structure of the lower atmosphere, and the surface radius of Pluto. In addition, REX measured thermal emission to a precision of 0.1K, from Pluto at 4.2-cm wavelength during two linear scans across the disk at close range when both the dayside and the night side were visible. A bonus in the equatorial thermal scan was the detection of a bistatic reflection of a specially designed uplink from near Pluto’s specular point. This work was supported by NASA’s New Horizons project.