SMART-1
Artist's impression of the SMART-1 mission ESA199399.jpg
Artist's impression of SMART-1
Mission typeTechnology
Lunar orbiter
OperatorESA
COSPAR ID2003-043C
SATCAT no.27949
WebsiteSMART-1
Mission duration2 years, 11 months, 6 days, 6 hours, 27 minutes, 36 seconds
Spacecraft properties
ManufacturerSwedish Space Corporation
Launch mass367 kilograms (809 lb)
Dry mass287 kilograms (633 lb)
Start of mission
Launch date27 September 2003, 23:14:46 (2003-09-27UTC23:14:46Z) UTC
RocketAriane 5G
Launch siteKourou ELA-3
ContractorArianespace
End of mission
Decay date3 September 2006, 05:42:22 (2006-09-03UTC05:42:23Z) UTC
Orbital parameters
Reference systemSelenocentric
Eccentricity0.352054
Periselene altitude2,205 kilometres (1,370 mi)
Aposelene altitude4,600 kilometres (2,900 mi)
Inclination90.26 degrees
Period4.95 hours
Epoch18 July 2005, 11:14:28 UTC
Lunar orbiter
Orbital insertion15 November 2004
Impact site34°15′43″S 46°11′35″W / 34.262°S 46.193°W / -34.262; -46.193[1]
ISO legacy mission insignia
Legacy ESA insignia for the SMART-1 mission  

SMART-1 was a Swedish-designed European Space Agency satellite that orbited around the Moon. It was launched on 27 September 2003 at 23:14 UTC from the Guiana Space Centre in Kourou, French Guiana. "SMART-1" stands for Small Missions for Advanced Research in Technology-1. On 3 September 2006 (05:42 UTC), SMART-1 was deliberately crashed into the Moon's surface, ending its mission.[2]

Spacecraft design

SMART-1 was about one metre across (3.3 ft), and lightweight in comparison to other probes. Its launch mass was 367 kg or 809 pounds, of which 287 kg (633 lb) was non-propellant.

It was propelled by a solar-powered Hall effect thruster (Snecma PPS-1350-G) using xenon propellant, of which there was 82 kg (50 litres by volume at a pressure of 150 bar) at launch. The thrusters used an electrostatic field to ionize the xenon and accelerate the ions to a high speed. This ion engine setup achieved a specific impulse of 16.1 kN·s/kg (1,640 seconds), more than three times the maximum for chemical rockets. Therefore, 1 kg of propellant (1/350 to 1/300 of the total mass of the spacecraft) produced a delta-v of about 45 m/s. The electric propulsion subsystem had a weight of 29 kg with a peak power consumption of 1,200 watts.[3] SMART-1 is the first in the program of ESA's Small Missions for Advanced Research and Technology.[4]

The solar arrays made 1,190 W available for powering the thruster, giving a nominal thrust of 68 mN, hence an acceleration of 0.2 mm/s² or 0.7 m/s per hour (i.e., just under 0.00002 g of acceleration). As with all ion-engine powered craft, orbital maneuvers were not carried out in short bursts but very gradually. The particular trajectory taken by SMART-1 to the Moon required thrusting for about one third to one half of every orbit. When spiralling away from the Earth thrusting was done on the perigee part of the orbit. At the end of the mission, the thruster had demonstrated the following capability:[5]

  • Thruster operating time: 5000 h
  • Xenon throughput: 82 kg
  • Total Impulse: 1.1 MN-s
  • Total ΔV: 3.9 km/s

As part of the European Space Agency's strategy to build very inexpensive and relatively small spaceships, the total cost of SMART-1 was a relatively small 110 million euros (about 170 million U.S. dollars). SMART-1 was designed and developed by the Swedish Space Corporation[6] on behalf of ESA. Assembly of the spacecraft was carried out by Saab Space in Linköping. Tests of the spacecraft were directed by Swedish Space Corporation and executed by Saab Space. The project manager at ESA was Giuseppe Racca and the project manager at the Swedish Space Corporation was Peter Rathsman; the Principal Project Scientist was Bernard Foing.

Instruments

AMIE

The Advanced Moon micro-Imager Experiment was a miniature colour camera for lunar imaging. The CCD camera with three filters of 750, 900 and 950 nm was able to take images with an average pixel resolution of 80 m (about 260 ft). The camera weighed 2.1 kg (about 4.5 lb) and had a power consumption of 9 watts.[7]

D-CIXS

The Demonstration of a Compact X-ray Spectrometer was an X-ray telescope for the identification of chemical elements on the lunar surface. It detected the x-ray fluorescence (XRF) of crystal compounds created through the interaction of the electron shell with the solar wind particles to measure the abundance of the three main components: magnesium, silicon and aluminium. The detection of iron, calcium and titanium depended on the solar activity. The detection range for x-rays was 0.5 to 10 keV. The spectrometer and XSM (described below) together weighed 5.2 kg and had a power consumption of 18 watts.

XSM

The X-ray solar monitor studied the solar variability to complement D-CIXS measurements.

SIR

The Smart-1 Infrared Spectrometer was an infrared spectrometer for the identification of mineral spectra of olivine and pyroxene. It detected wavelengths from 0.93 to 2.4 µm with 256 channels. The package weighed 2.3 kg and had a power consumption of 4.1 watts.[8]

EPDP

The Electric Propulsion Diagnostic Package was to acquire data on the new propulsion system on SMART-1. The package weighed 0.8 kg and had a power consumption of 1.8 watts.[9]

SPEDE

The Spacecraft Potential, Electron and Dust Experiment. The experiment weighed 0.8 kg and had a power consumption of 1.8 watts. Its function was to measure the properties and density of the plasma around the spacecraft, either as a Langmuir probe or as an electric field probe. SPEDE observed the emission of the spacecraft's ion engine and the "wake" the Moon leaves to the solar wind. Unlike most other instruments that have to be shut down to prevent damage, SPEDE could keep measuring inside radiation belts and in solar storms, such as the Halloween 2003 solar storms.[10][11] It was built by Finnish Meteorological Institute and its name was intentionally chosen so that its acronym is the same as the nickname of Spede Pasanen, a famous Finnish movie actor, movie producer, and inventor. The algorithms developed for SPEDE were later used in the ESA lander Philae.[11]

KATE

Ka band TT&C (telemetry, tracking and control) Experiment. The experiment weighed 6.2 kg and had a power consumption of 26 watts.

Flight

SMART-1 was launched 27 September 2003 together with Insat 3E and eBird 1, by an Ariane 5 rocket from the Guiana Space Centre in French Guiana. After 42 minutes it was released into a geostationary transfer orbit of 7,035 × 42,223 km. From there it used its Solar Electric Primary Propulsion (SEPP) to gradually spiral out during thirteen months.

The orbit can be seen up to 26 October 2004 at spaceref.com, when the orbit was 179,718 × 305,214 km. On that date, after the 289th engine pulse, the SEPP had accumulated a total on-time of nearly 3,648 hours out of a total flight time of 8,000 hours, hence a little less than half of its total mission. It consumed about 58.8 kg of xenon and produced a delta-v of 2,737 m/s (46.5 m/s per kg xenon, 0.75 m/s per hour on-time). It was powered on again on 15 November for a planned burn of 4.5 days to enter fully into lunar orbit. It took until February 2005 using the electric thruster to decelerate into the final orbit 300-3,000 km above the Moon's surface.[12] The end of mission performance demonstrated by the propulsion system is stated above.

Summary of osculating geocentric orbital elements
Epoch (UTC) Perigee (km) Apogee (km) Eccentricity Inclination (deg)
(to Earth equator)
Period (h)
27 September 2003 ~7,035 ~42,223 ~0.714 ~6.9 ~10.6833
26 October 2003, 21:20:00.0 8,687.994 44,178.401 0.671323 6.914596 11.880450
19 November 2003, 04:29:48.4 10,843.910 46,582.165 0.622335 6.861354 13.450152
19 December 2003, 06:41:47.6 13,390.351 49,369.049 0.573280 6.825455 15.366738
29 December 2003, 05:21:47.8 17,235.509 54,102.642 0.516794 6.847919 18.622855
19 February 2004, 22:46:08.6 20,690.564 65,869.222 0.521936 6.906311 24.890737
19 March 2004, 00:40:52.7 20,683.545 66,915.919 0.527770 6.979793 25.340528
25 August 2004, 00:00:00 37,791.261 240,824.363 0.728721 6.939815 143.738051
19 October 2004, 21:30:45.9 69,959.278 292,632.424 0.614115 12.477919 213.397970
24 October 2004, 06:12:40.9 179,717.894 305,214.126 0.258791 20.591807 330.053834

After its last perigee on 2 November,[13] on 11 November 2004 it passed through the L1 Lagrangian Point and into the area dominated by the Moon's gravitational influence, and at 1748 UT on 15 November passed the first periselene of its lunar orbit. The osculating orbit on that date was 6,704 × 53,208 km,[14] with an orbital period of 129 hours, although the actual orbit was accomplished in only 89 hours. This illustrates the significant impact that the engine burns have on the orbit and marks the meaning of the osculating orbit, which is the orbit that would be travelled by the spacecraft if at that instant all perturbations, including thrust, would cease.

Summary of osculating selenocentric orbital elements
Epoch (UTC) Periselene (km) Aposelene (km) Eccentricity Inclination (deg)
(to Moon equator)
Period (h)
15 November 2004, 17:47:12.1 6,700.720 53,215.151 0.776329 81.085 129.247777
4 December 2004 10:37:47.3 5,454.925 20,713.095 0.583085 83.035 37.304959
9 January 2005, 15:24:55.0 2,751.511 6,941.359 0.432261 87.892 8.409861
28 February 2005, 05:18:39.9 2,208.659 4,618.220 0.352952 90.063603 4.970998
25 April 2005, 08:19:05.4 2,283.738 4,523.111 0.328988 90.141407 4.949137
16 May 2005, 09:08:52.9 2,291.250 4,515.857 0.326807 89.734929 4.949919
20 June 2005, 10:21:37.1 2,256.090 4,549.196 0.336960 90.232619 4.947432
18 July 2005, 11:14:28.0 2,204.645 4,600.376 0.352054 90.263741 4.947143

ESA announced on 15 February 2005 the endorsement of a proposal to extend the mission of SMART-1 by one year until August 2006. This date was later shifted to 3 September 2006 to enable further scientific observations from Earth.[15]

Lunar impact

SMART-1 impact flash

SMART-1 impacted the Moon's surface, as planned, on 3 September 2006 at 05:42:22 UTC, ending its mission. Moving at approximately 2,000 m/s (4,500 mph), SMART-1 created an impact visible with ground telescopes from Earth. It is hoped that not only will this provide some data simulating a meteor impact, but also that it might expose materials in the ground, like water ice, to spectroscopic analysis.

Location of the Smart 1 impact, in relation to other moon objects.

ESA originally estimated that impact occurred at 34°24′S 46°12′W / 34.4°S 46.2°W / -34.4; -46.2.[16] In 2017, the impact site was identified from Lunar Reconnaissance Orbiter data at 34°15′43″S 46°11′35″W / 34.262°S 46.193°W / -34.262; -46.193[1]. At the time of impact, the Moon was visible in North and South America, and places in the Pacific Ocean, but not Europe, Africa, or western Asia.

This project has generated data and know-how that will be used for other missions, such as the ESA's BepiColombo mission to Mercury.

Important events and discoveries

  • September 27, 2003: SMART-1 launched from the European Spaceport in Kourou by an Ariane 5 launcher.
  • June 17, 2004: SMART-1 took a test image of Earth with the camera that would later be used for Moon closeup pictures. It shows parts of Europe and Africa. It was taken on May 21 with the AMIE camera.
  • November 2, 2004: Last perigee of Earth orbit.
  • November 15, 2004: First perilune of lunar orbit.
  • January 15, 2005: Calcium detected in Mare Crisium.
  • January 26, 2005: First close up pictures of the lunar surface sent back.
  • February 27, 2005: Reached final orbit around the Moon with an orbital period of about 5 hours.
  • April 15, 2005: The search for PELs begins.
  • September 3, 2006: Mission ends with a planned crash into the Moon during orbit number 2,890.[17]

See also

References

  1. ^ a b Klesman, Alison (22 Sep 2017). "New observations reveal a lunar orbiter's final resting place". Astronomy Magazine. Retrieved 27 Sep 2017.
  2. ^ "Probe crashes into Moon's surface". BBC News. September 3, 2006. Retrieved May 23, 2010.
  3. ^ Kugelberg J.; Bodin P.; Persson S.; Rathsman P. (2004). "Accommodating electric propulsion on SMART-1". Acta Astronautica. 55 (2): 121–130. Bibcode:2004AcAau..55..121K. doi:10.1016/j.actaastro.2004.04.003.
  4. ^ Foing, Bernard H.; Koschny, D.; Grieger, B.; Josset, J.-L.; et al. "SMART-1 Results and Targets for LRO". NASA. NASA Technical Reports Server. Retrieved 5 October 2011.
  5. ^ Cornu, N., et al., "The PPS 1350-G Qualification Demonstration: 10500 hrs on the Ground and 5000 hrs in Flight," AIAA Paper 2007-5197, July 2007.
  6. ^ Swedish Space Corporation
  7. ^ Josset J. L.; Beauvivre S.; Cerroni P.; De Sanctis M. C.; et al. (2006). "Science objectives and first results from the SMART-1/AMIE multicolour micro-camera". Advances in Space Research. 37: 14–20. Bibcode:2006AdSpR..37...14J. doi:10.1016/j.asr.2005.06.078.
  8. ^ Basilevsky A. T.; Keller H. U.; Nathues A.; Mall J.; et al. (2004). "Scientific objectives and selection of targets for the SMART-1 Infrared Spectrometer (SIR)". Planetary and Space Science. 52 (14): 1261–1285. Bibcode:2004P&SS...52.1261B. doi:10.1016/j.pss.2004.09.002.
  9. ^ Di Cara D. M.; Estublier D. (2005). "Smart-1: An analysis of flight data". Acta Astronautica. 57 (2–8): 250–256. Bibcode:2005AcAau..57..250D. doi:10.1016/j.actaastro.2005.03.036.
  10. ^ http://sci.esa.int/smart-1/31415-instruments/
  11. ^ a b Schmidt, Walter; Mälkki, Anssi (2014). "SMART-1 SPEDE: Results and Legacy after 10 Years". 16. Bibcode:2014EGUGA..1613174S.CS1 maint: Uses authors parameter (link)
  12. ^ Rathsman P.; Kugelberg J.; Bodin P.; Racca G. D.; et al. (2005). "SMART-1: Development and lessons learnt". Acta Astronautica. 57 (2–8): 455–468. Bibcode:2005AcAau..57..455R. doi:10.1016/j.actaastro.2005.03.041.
  13. ^ SMART-1: On Course for Lunar Capture | Moon Today - Your Daily Source of Moon News Archived 2005-11-02 at the Wayback Machine
  14. ^ SMART-1 completes its first orbit around the Moon | Moon Today - Your Daily Source of Moon News Archived 2004-12-15 at the Wayback Machine
  15. ^ ESA Portal - SMART-1 manoeuvres prepare for mission end
  16. ^ "SMART-1 impacts Moon". European Space Agency. 3 Sep 2006. Archived from the original on 5 September 2006. Retrieved 3 Sep 2006.
  17. ^ ESA - SMART-1 - Intense final hours for SMART-1
General
  • Kaydash V., Kreslavsky M., Shkuratov Yu., Gerasimenko S., Pinet P., Chevrel S., Josset J.-L., Beauvivre S., Almeida M., Foing B. (2007). "PHOTOMETRIC CHARACTERIZATION OF SELECTED LUNAR SITES BY SMART-1 AMIE DATA". Lunar Planetary Science, XXXVIII, abstract 1535, [1].

External links

  • Official website
  • ESA SMART-1 scientific website
  • SMART-1 Mission Profile by NASA's Solar System Exploration
  • Observation of the Impact of Smart-1
  • SMART 1 on Serbian science portal Viva fizika
  • SMART-1, Europe at the Moon