ESA Science & Technology - SMART-1 Mission Review

Recent Results

Click on an image in the results below to access either a movie (in AVI format) or a high resolution image. Some of the files are large and may take a short while to download.

Earth Rise!
Date: 29 August 2006, 19:00 UT Instrument: AMIE Type: Movie  Target: Earth - 44.9° W, 19.2° S Description: AMIE was pointed back towards the Earth to capture, in the best tradition of many previous lunar missions, a view of our home planet.  The image is centred on Brazil (north is to the left) with the Kourou launch site also visible.
Lunar Surface
Date: 2 September 2006, 15:19 - 17:34 UT Instrument: AMIE Type: Movie Description: During SMART-1's final orbits on 1 and 2 September, the spacecraft was passing at extremely low altitude over the Moon's surface, which was in darkness, prompting scientists to take advantage of this unique observational situation by pointing the AMIE camera laterally toward the Moon's limb (horizon).
South Pole-Aitken Basin
Date: Instrument: AMIE Target: South Pole-Aitken Basin at 173.4° E & 16.8° S Type: Image  Description: The Aitken Basin is the largest and oldest known impact crater basin in the solar system and the deepest depression in the Moon. The basin is 2600 km in diameter and extends from the South Pole to the Aitken Crater. AMIE was able to image the area under ideal illumination conditions, which will afford scientists an opportunity to compare AMIE images with existing data of the same area gathered by previous lunar missions.
Illumination conditions at North Pole
Date: 2005 Instrument: AMIE Type: Image  Description: This mosaic is valuable as it shows illumination conditions at the region. It is important to understand global illumination conditions to help in planning the location of future landing sites and, later, possible bases, on the Moon.
Radio Observations
Date: 3 September 2006 Instrument: Australia Telescope Compact Array (CSIRO) Type: Animated Gif Description: The SMART-1 carrier radio signal stopped at 05:42 UT, when the spacecraft hit the Moon. Other radio telescopes involved in tracking the probe - the German-Chilean TIGO (BKG) 6-metre antenna in Chile and the Mount Pleasant Observatory of the University of Tasmania (Australia) - also heard SMART-1's final signal.

Overview of Mission Operations

The SMART-1 mission operations were run from ESOC at Darmstadt and fell into three distinct categories:

• Operate the Electric Propulsion and get to the Moon
• Collect and analyse technology demonstration data
• Run Moon scientific operations maximising recovery of data

To successfully operate this programme, particularly during the Earth bound phase of the mission, a number of ground stations across the globe were used.

Learning to Fly
Throughout the mission ground control teams had to learn to fly with an ion drive and plan for gravitational resonances with the Moon - small changes in applied thrust could mean the recalculation of entire schedules.

At the Moon
Once at the Moon, the SMART-1 mission was extended several times utilising every possible means to maximise the overall duration and guarantee an impact on the lunar near side. This last tasks, due to the lack of fuel onboard, was achieved through a complex series of reaction wheel offloadings lasting 65 orbits.

Final Orbits
Having performed a correction to bring the impact onto the lunar near side a final manoeuvre was required just 36 hours before impact. Detailed analysis of the projected impact region suggested a crater rim on an earlier orbit might be higher than originally anticipated. One final alteration was required to boost the perilune of the penultimate orbit by 600 m.

Overview of Mission Technology

The SMART-1 technology goals have been fully achieved:

• Earth-Moon transfer powered by Solar Electric Primary Propulsion and making use of the lunar gravity assists
• Moon orbit maintenance during scientific operational phase using Electric Propulsion
• Technology Demonstration in:
  - New communication techniques: Laser link & Ka band antenna
  - Autonomous navigation: OBAN
  - Miniaturisation: x-ray & infrared spectrometers
  - Novel spacecraft technologies: on-board computer & lithium ion batteries

Ion Drive
On SMART-1, Solar Electric Propulsion has been used as primary propulsion system for the first time on a European spacecraft.  This is an important step for future interplanetary missions because:

• A much lower propellant mass is needed
• Long trips in shorter time are possible
• Less constraints are imposed on launch windows
• A larger choice of target destinations is offered
• Manoeuvrability and flexibility are enhanced

Timeline

Overview of Mission Science

Mini-Instruments European Technologies
Due to the compact nature of the SMART-1 spacecraft and launch mass contraints the instrument payload had to weigh no more than 19 kg.

Science & Exploration Themes

• How do Earth like Planets work?
  
  Geophysical observations: volcanism, tectonics, craters, erosion, space weather, ices
• How do Rocky planets form and evolve?
  
  Geochemistry: chemical composition, Earth-Moon origin, Moon evolution, accretion, collisions, giant bombardment
• Preparing Future Lunar/Planetary Explorations
  
  Lunar Resources Survey: minerals, volatiles, illumination
  High Resolution Maps: for future landing sites
  Support to future missions and lunar exploration
  
• Public Outreach, inspiration and education