Titan Fly-by - 7 February 2009
5 February 2009
Saturday 7 February the Cassini spacecraft returns to Saturn's largest moon for the mission's fifty-first targeted encounter with Titan. The closest approach to Titan occurs at 08:50:51 UTC at an altitude of 960 kilometres above the surface and at a speed of 6.3 kilometres per second. The latitude at closest approach is 33.7°S and the encounter occurs on orbit number 102.This encounter is set up with two manoeuvres: an apoapsis manoeuvre on 23 January, and a Titan approach manoeuvre, scheduled for 3 February. T-50 is the fourteenth in a series of outbound encounters and the sixth Titan encounter in Cassini's Equinox Mission. It occurs just under five days after Saturn closest approach.
Science Highlights
- Ion and Neutral Mass Spectrometer (INMS)
Closest approach at T50 features an INMS prime observation to measure the boundary between the wake side and inner flank magnetospheric interaction region at mid southern latitudes. - Cassini Radar (RADAR)
The instrument rides along with INMS at closest approach. During the fly-by, the instrument will collect SAR of the mountain ranges southwest of Tsegihi that were suggested in VIMS data. Altimetry inbound and outbound completes the instrument's plans. - Composite Infrared Spectrometer (CIRS)
On T50 CIRS focuses on mapping temperatures, trace hydrocarbons, nitriles and oxygen compounds in Titan's stratosphere. CIRS also continues to search for weak isotopes and new gas species. - Visual and Infrared Mapping Spectrometer (VIMS)
During T50, VIMS will observe Titan from a large distance and will conduct cloud mapping. It will ride along with other instruments to probe Titan's atmosphere at the limb. - Ultraviolet Imaging Spectrograph (UVIS)
UVIS will obtain an image cube of Titan's atmosphere at EUV and FUV wavelengths by sweeping its slit across the disk. These cubes provide spectral and spatial information on nitrogen emissions, H emission and absorption, absorption by simple hydrocarbons, and the scattering properties of haze aerosols. This is one of many such cubes gathered over the course of the mission to provide latitude and seasonal coverage of Titan's middle atmosphere and stratosphere. - Imaging Science Subsystem (ISS)
ISS will monitor clouds (no illuminated prime observations). - Magnetospheric Imaging Instrument (MIMI)
MIMI will measure energetic ion and electron energy input to Titan's atmosphere. - Dual Technique Magnetometer (MAG)
T50 is an upstream flank-in fly-by with a minimum altitude of < 1000 kilometres. The geometry of this fly-by is suitable to study the magnetic pileup region across the nightside hemisphere. T50 also takes place in Saturn's near-noon sector (10.5 hours SLT), where Titan could be found in the magnetosheath if the solar wind pressure is high. - Radio and Plasma Wave Science (RPWS)
RPWS will measure thermal plasmas in Titan's ionosphere and surrounding environment; search for lightning in Titan's atmosphere; and investigate the interaction of Titan with Saturn's magnetosphere.
Table of Events
9 January 2009
Time UTC | Time wrt T-50 |
Activity |
15:16:00 | -28d 18h | Start of sequence S47 that contains Titan-50 |
4 February 2009
Time UTC | Time wrt T-50 |
Activity |
04:34:00 | -03d 04h | TM #181 prime. Titan-50 targeting manoeuvre |
5 February 2009
Time UTC | Time wrt T-50 |
Activity |
04:19:00 | -02d 05h | TM #181 backup |
6 February 2009
Time UTC | Time wrt T-50 |
Activity |
13:19:00 | -19h 31m | Start of the TOST segment |
13:19:00 | -19h 31m | Turn cameras to Titan |
13:59:00 | -18h 51m | New waypoint |
13:59:00 | -18h 51m | Deadtime 15 minutes long; used to accommodate changes in fly-by time |
14:14:31 | -18h 36m | Cloud and global mapping - VIMS. Stare at Titan for cloud and global mapping |
19:50:51 | -13h 00m | Titan atmospheric observations-CIRS. obtain information on CO, HCN, CH4. Integrate on disk at airmass 1.5-2.0 |
23:20:51 | -09h 30m | Titan atmospheric observations-CIRS. obtain vertical profiles of temperatures in Titan's stratosphere |
7 February 2009
Time UTC | Time wrt T-50 |
Activity |
03:20:51 | -05h 30m | Titan RADAR observations. Inbound radiometry |
06:50:51 | -02h 00m | Titan RADAR observations. Inbound scatterometry |
07:38:51 | -01h 12m | Transition to thruster control |
07:39:51 | -01h 11m | Titan RADAR observations. Inbound HiSAR |
08:20:51 | -00h 30m | Titan RADAR observations. Inbound altimetry |
08:38:51 | -00h 12m | Atmospheric observations-INMS. INMS with RADAR ride-along SAR at closest approach |
08:48:25 | -00h 02m | Earth occultation10 minute duration |
08:48: | -00h 02m | Sun occultation9 minute duration |
08:50:51 | +00h 00m | Titan-50 fly-by Closest Approach Time. Altitude = 960 km, speed = 6.3 kms-1, 136° phase at closest approach |
09:19:58 | +00h 29m | Ascending ring plane crossing |
09:02:51 | +00h 12m | Titan RADAR observations. outbound altimetry |
09:20:51 | +00h 30m | Titan RADAR observations. outbound HiSAR |
09:40:51 | +00h 50m | Transition off of thruster control |
10:02:32 | +01h 12m | Titan RADAR observations. outbound scatterometry |
10:50:51 | +02h 00m | Titan RADAR observations. outbound radiometry |
14:50:51 | +06h 00m | Titan atmospheric observations-UVIS. EUVFUV: several slow scans across Titan's visible hemisphere to form spectral images |
17:50:51 | +09h 00m | Titan surface observations-ISS. Monitoring for surface/atmosphere changes; attempt to see surface colour variations; monitor limb hazes, 1-3 km/px |
18:50:51 | +10h 00m | Titan atmospheric observations-CIRS. obtain information on the thermal structure of Titan's stratosphere |
21:50:51 | +13h 00m | Titan surface observations-ISS. Monitoring for surface/atmosphere changes; attempt to see surface colour variations; monitor limb hazes, 1-3 km/px |
22:20:51 | +13h 30m | Titan atmospheric observations-CIRS. obtain information on the thermal structure of Titan's stratosphere |
8 February 2009
Time UTC | Time wrt T-50 |
Activity |
02:29:27 | +17h 39m | Apoapse |
02:50:51 | +18h 00m | Titan surface observations-ISS. Long range monitoring |
03:20:51 | +18h 30m | Deadtime, 18 minutes and 8 seconds long. Used to accommodate changes in fly-by time |
03:39:00 | +18h 49m | Turn to Earth-line |
Last Update: 1 September 2019