1999-066A
XMM (X-ray Multi Mirror) was the Cornerstone 2 (CS2) mission. Prime contractor is DaimlerChrysler Dornier/Friedrichshafen. Control from MOC/Darmstadt with science command from VILSPA. Ground stations at CSG and Perth. Mass is 3764 kg full 3234 kg dry.
Prop is 490 kg, SM is 810 kg, mirror is 1760 kg, FP assembly is 480 kg, tube is 210 kg.
The telescope tube is 7.0m long, total size 10.0m. Spacecraft is Focal plane assembly, service and propulsion module, and three mirror modules. Each mirror module has 58 X-ray mirrors. and has a diameter of 0.7m and focal length of 7.500m, spatial resolution of 5" FWHM and 15" HPD. Effective aperture is 8 cm at 1 keV.
AOCS orbit adjust with 4 thrusters of total 90N thrust. Loading capacity is 530 kg of hydrazine.
The EPC stage made a suborbital flight for impact near the Galapagos. The high inclination trajectory led to the first use of a French Navy ship, Monge, as a downrange tracking system. A paper on reentry observations shows that it descended through 80 km at MET 6096s, i.e. 1613:43 UTC, and the ascending node was -83.2 deg longitude at T=6000s. This corresponds to 238.8 deg RA.
The initial version of the Ariane 5 EPS upper stage can only make a single burn, so mission 504 flew an unusual direct ascent trajectory to its highly elliptical orbit. The EPC main stage separated at 1442 UTC in a high energy suborbital trajectory with a velocity of around 7.8 km/s, and impact near the Galapagos Islands (I don't know what the apogee was). The EPS upper stage ignited and made a long 16 minute burn to accelerate the vehicle to over 9 km/s and 1880 km altitude. XMM separated from the EPS upper stage at 1501 UTC, and is in an 838 x 112473 km x 40.0 deg transfer orbit, very close to the planned one. The first apogee burn will be on Dec 11.
XMM is Arianespace's first commercial contract to fly on Ariane 5, albeit with ESA as the customer. The success of flight V119 will bolster confidence that the early problems with the vehicle are behind it, and 2000 should see a ramp up of commercial geostationary comsat launches on Ariane 5
XMM (X-ray Multi-Mirror Mission), built by DaimlerChrysler Dornier Satellitensystem, is a large X-ray observatory which will complement NASA's Chandra X-ray Observatory. XMM has larger collecting area but poorer spatial resolution, so it will be better at getting detailed spectra of bright and moderately faint X-ray sources, while Chandra will be better at detecting the very faintest X-ray sources and at distinguishing spectral details in different parts of a source (for instance, separating a pulsar from a supernova remnant or a quasar from a cluster of galaxies). The claim on the ESA web site that XMM "will see infinitely more than any previous X-ray satellite" (http://www.estec.esa.nl/spdwww/xmm/factsheet.html) is an embarrassingly ridiculous misstatement, but I certainly expect XMM to make many important discoveries and be one of the most important space science missions.
XMM has three similar X-ray telescopes. One of the telescopes images directly onto the EPIC-pn CCD camera; the other two have Reflection Grating Spectrometers (RGS) which split the light, sending images to the EPIC-MOS cameras and dispersed spectra to the RFC-MOS cameras. XMM also carries an 0.30-meter aperture optical/ultraviolet telescope, the Optical Monitor, which will allow simultaneous measurements of the optical and ultraviolet light from the source being studied with the X-ray telescopes.
XMM's hydrazine propulsion system has eight 22N thrusters which will be used to raise the perigee to around 7000 km. Dry mass of XMM is 3234 kg, and it carries 530 kg of hydrazine fuel at launch. Control of the XMM spacecraft will be from ESOC/Darmstadt, while the instruments will be controlled from the VILSPA/Madrid station. The instruments will not be fully activated until early next year, when XMM is in its final orbit and VILSPA is ready for operation, so it will be a while before we know whether the telescope is working correctly. The Leicester University X-ray group will support the scientific analysis of data from XMM. There's a strong heritage of world-class X-ray astronomy in Europe, with the British groups at Leicester and Mullard Space Science Lab flying early sounding rockets and the Ariel 5 satellite in the 1970s and the Birmingham group (TTM/Kvant), the Utrecht group and the ESA team at ESTEC in Holland, the German groups at MPE/Garching (ROSAT) and now AIP/Potsdam, and a number of institutes (Milano, Bologna, Palermo, Roma) in Italy (BeppoSAX), as well as a bunch of places that don't do hardware but are very strong in data analysis and theory, like Andy Fabian's team in Cambridge. Oh, and let's not forget the Danes and Toulouse and Southampton and ... I'm sure whoever else I left out will remind me in no uncertain terms. The point is that while in many fields of space exploration Europe plays second rank to the US, in X-ray astronomy it's an equal partner.
XMM was renamed XMM-Newton on 2000 Feb 9 after Isaac Newton (1642-1727).
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| XMM |
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| Date | Time | Event | Orbit |
|---|
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| 1999 Dec 10 | 1432:07 | Launch by Ariane 504 CSG ELA3 |
| | 1434:25 | EAP sep, 68 km, 2.10 km/s |
| | 1435:16 | Fairing sep |
| | 1440 | 128 km, 6.0 km/s
| |
| 1442:00 | T+9:53 EPC sep | 50? x 2000?? x 40.0 |
| | 1442:14 | T+10:07 EPS-1 burn |
| | 1459:03 | T+26:56 EPS MECO, 1882 km, 9.07 km/s |
| | 1501:45 | T+29:08 EPS sep 8.82 km/s | 850 x 114000 x 40 |
| | 1521? | EPC apogee |
| | 1613:43 | EPC reentry 80 km |
| 1999 Dec 10 | 1541 | Solar array deploy |
| 1999 Dec 11 | 1220 | AOCS DV-1A at apogee 1, 53min | 2531 x 114042 x 39.9 |
| | 1413 | AOCS DV-1B 99min | 4897 x 114002 x 39.9 |
| 1999 Dec 13 | 1225 | AOCS DV-2 64min | 6480 x 113990 x 39.9 |
| 1999 Dec 15 | 1210 | AOCS DV-3 35min | 7359 x 113975 x 39.9 |
| 1999 Dec 16 | 1130 | AOCS DV-4 1:32 | 7365 x 113774 x 39.9 (est) |
| 1999 Dec 17 | 1000 | Outer X-ray Door open |
| 1999 Dec 18 | 1500s | OM Door open |
| 1999 Dec 20 | s | Quiescent mode |
| 2000 Jan 4 | s | Reactivated |
| 2000 Jan 4 | | Commissioning phase |
| 2000 Jan | | EPIC door open |
| 2000 Jan 25 | | RGS 2 door open |
| 2000 Feb 7 | | RGS 1 door open |
Payload:
- X-ray mirror module 1
- X-ray mirror module 2
- MOS-1 EPIC-MOS CCD camera
- RGS-1 grating
- RFC-1 RGS Focal Camera MOS CCD
- X-ray mirror module 3
- MOS-2 EPIC MOS CCD camera
- RGS-2 grating
- RFC-2 MOS CCD camera
- OM Optical Monitor, 0.30m UV/Opt telescope f/12.7, 1600-6000A
- OM CCD, 2048 x 2048 with MCP intensification
- AOCS Hydrazine thrusters, 8 (Fiat Avio BPD)
