Gateway to Grand Finale – NASA's cassini makes last and fateful close flyby with Saturn's moon 'Titan'
NASA's Cassini spacecraft successfully made its 127th and last close encounter with Saturn's hazy moon last week, enabling scientists to get their first glimpses of Titan's seas, weather patterns and rippling sand dunes.
On April 21 at 11:08 p.m. PDT (2:08 a.m. EDT on April 22), the spacecraft passed at an altitude of about 608 miles (979 kilometers) above the surface of Saturn's moon, beginning its final set of 22 orbits around the ringed planet.
After buzzing Titan, Cassini coasted onward, reaching the farthest point in its orbital path around Saturn at 8:46 p.m. PDT (11:46 p.m. EDT) on April 22. This point, called apoapse, is where each new Cassini lap around Saturn begins.
Following the encounter, Cassini transmitted its images and other data to Earth. Scientists with Cassini's radar investigation will be looking this week at their final set of new radar images of the hydrocarbon seas and lakes that spread across Titan's north polar region.
"Cassini's up-close exploration of Titan is now behind us, but the rich volume of data the spacecraft has collected will fuel scientific study for decades to come," said Linda Spilker, the mission's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.
The flyby also put Cassini on course for its dramatic last act, known as the Grand Finale.
Technically, Cassini began its 'Grand Finale' orbits at this time, but since the excitement of the finale begins in earnest on April 26 with the first ultra-close dive past Saturn, the mission is celebrating the latter milestone as the formal beginning of the finale.
Cassini's first finale dive will take place on April 26 at 2 a.m. PDT (5 a.m. EDT). The spacecraft will be out of contact during the dive and for about a day afterward while it makes science observations from close to the planet.
NASA says the earliest time Cassini is scheduled to make radio contact with Earth is 12:05 a.m. PDT (3:05 a.m. EDT) on April 27. Images and other data are expected to begin flowing in shortly after communication is established.