January 14 2005 begins with the earth passing directly in between the Sun and
Saturn an opposition so perfect that it occurs maybe twice per millennium
meanwhile the Huygens probe quietly entering the Saturnian system is about
to end its seven-year journey as Huygens approaches the inner planets cluster
around the distant Sun Saturn appears almost as large as Orion a few moons are
visible as white dots aligned with Saturn's rings while Titan its largest
moon is already well resolved Huygens is destined for Titan a
mysterious world larger than the planet Mercury and shrouded by a thick brownish
orange atmosphere the details of its surface have never been seen Huygens
speed increases to near 6 km/s and Titans disk quickly obscures our view of
Saturn and it's more intimate moons as the probe enters Titan's atmosphere the
heat shield reduces the speed some 15 fold within a few minutes the main
parachute reduces the speed further 15 minutes later the smaller stabilizer
chute allows a faster descent at first but slows as Huygens enters the lower
denser parts of Titan's atmosphere Huygens is approaching a dark Valley
between brighter hilly regions beyond the hills to the left two dark
parallel lines appear which are later discovered to be part of a vast system
of dunes which surrounds the moon at 21 kilometers altitude the probe moves
through a thin haze layer as seen on the horizon
the bright area near the center top is the glow of titans haze illuminated by
the Sun a complicated system of drainage channels some hundreds of metres wide
and kilometers long are seen cut into the hillside these are probably the
result of runoff from methane rain stereographic imagery reveals hills to
the left to be perhaps a few hundred meters tall
while features in the valley are tens of meters in height for most of the descent
the probe travels eastward above Titans surface however below seven kilometers
altitude the motion reverses into a backward westward motion it reverses
again at one kilometer altitude and we move slowly south eastward
hang on as Huygens lands on Titan's surface near a water ice outcropping
Ridge another westward looking view of the descent from 31 kilometers so the
area of titan over which the probe has just flown this affords us a good view
of the drainage channels and apparent shoreline more dark lowlands appear and
rough pitted hillside to the left spectra of the surface suggest of the
bright areas our water ice in the darker areas are a type of hydrocarbon mixture
that has never been produced in the laboratory the small white dot in the
lower center part of scene tracts our progress over Titans surface we see the
reversal and direction at 7 kilometers altitude and we fly over the ridge near
where we will land as we approach the surface our
perspective brings the topography to life we see that although there are
rivers in a short line the basin is dry below there are distinct signs of
erosion which crafted the rugged ridge line Huygens sinks into one of these
gullies we experience a relatively soft landing on Titan's surface the view from
the surface reveals an amazingly earth-like picture of a dry riverbed
with distant hills which are a few meters in height some seconds after
impact the shadow of Huygens parachute drifts across the scene the heat from
the surface science lamp and the probes skin vaporizes methane from Titan
surface which is about 180 centigrade degrees below freezing near the probe
the ground is littered with water ice rocks and smaller pebbles which could be
made of water ice or hydrocarbons or some combination thereof although we now
know more than ever about this mysterious world many questions remain
unanswered where is the vast reservoir of liquid methane necessary to replenish
the atmosphere where and how often does it bring on Titan how does the methane
get recirculated into the atmosphere what materials make up the surface what
processes create and shape the hills dunes and valleys
we are getting a TV picture
Oh
on diet please