Transit (astronomy) of Mercury from Saturn and a transit of Venus from Saturn. No missions were planned to coincide with the transit of Earth visible from Mars on 11 May 1984 and the Viking missions had been terminated a year previously. Consequently, the next opportunity to observe such an alignment will be in 2084. On December 21, 2012, the "Cassini–Huygens" probe, in orbit around Saturn, observed the planet Venus transiting the Sun. On 3 June 2014, the Mars rover "Curiosity" observed the planet Mercury transiting the Sun, marking the first time a planetary transit has been observed from a celestial body besides
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