Todd J. Barber, Cassini lead propulsion engineer
We've inched ever closer to the end of Cassini's prime mission with a very busy April now behind us. At the beginning of the month, the flight team was still buzzing about the latest Cassini news from Titan in late March. Evidence is mounting that this second-largest moon in the solar system may have a subsurface ocean of liquid water and ammonia! I've often said this, but it continues to be borne out in the data -- it seems as if Titan and Earth are more similar the more we learn about this largest moon of Saturn. The March 21 issue of the prestigious journal "Science" lays out the evidence in detail. If true, Titan would join Europa and perhaps other Jovian satellites (and potentially Enceladus) on the short list of very exciting targets for exobiologists, scientists seeking out habitable environments or even life far from Earth.
As we did last fall, we are currently running a 2008 edition of the "Cassini Scientist for a Day" essay contest. The May 8th deadline for students in grades 5-12 is approaching quickly. I really enjoyed reading some of the essays from the 2007 contest, as well as checking out the images enabled by the winning entries. I do hope those of you in grades 5-12 will consider being a part of planetary science history. We always like to invite the public along for the journey on these robotic missions of endless discovery and wonder. Having the contest winners essentially at the "helm" of Cassini raises that participation to a whole other level!
Personally, I was thrilled to again volunteer with Cassini's own Jane Houston Jones and the Sidewalk Astronomers, showing hundreds of people their first view of Saturn in a telescope during April's first quarter moon. Acting more like a circus barker than an amateur astronomer, I "ambushed" as many passersby as I could in Old Town Pasadena. The first view of Saturn's rings is an experience few forget, but there is no time like the present to seek out a telescope and see it for yourselves. This is particularly true because the tilt of Saturn's rings is rendering them less visible all the time. In fact, just as they did for Galileo himself in 1612, on September 4, 2009, Saturn's rings will disappear from view as seen by all Earth-bound and Earth-orbiting telescopes. Only Cassini from its orbital perch will be able to see these mysterious features that have inspired many and have elicited more than a few gasps.