Extraterrestrial skies Mars appears to be the angular diameter as seen from Earth (0.35°), and sends 40% of the light, approximately the brightness of a slightly cloudy afternoon on Earth. On June 3, 2014, the "Curiosity" rover on Mars observed the planet Mercury transiting the Sun, marking the first time a planetary transit has been observed from a celestial body besides Earth. Mars has two small moons: Phobos and Deimos. From the Martian surface, Phobos has one-third to one-half the angular diameter of the Sun while Deimos is barely more than a dot (only 2′ angular diameter). The orbital period of Phobos
NASA Earth Science chemistry, ocean and land ecosystems. It was a NASA scientist, Dr. James Hansen, who first alerted the world to the dangers of global warming due to greenhouse gases emitted by human burning of fossil fuels. Earth Science research also provides the foundations of understanding for the search for extraterrestrial life through the NASA Astrobiology Institute (NAI), in which the focus is often on the extreme conditions for life to survive. NASA Earth Science NASA Earth Science, formerly called the NASA Earth Science Enterprise (ESE), formerly called Mission To Planet Earth (MTPE), is a NASA research program "to develop a scientific