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10th European Space Weather Week , November 18-22, 2013, Antwerp, Belgium
Space debris in the Near-Earth space:
Impact on space missions Coronas-F and Coronas-Photon
Sergey Kuzin, Sergey Shestov, Ulyanov Artem
LPI, Moscow, Russia
The work has been supported by the FP-7
eHEROES Project № 284461 of the European Commission
Motivation
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Space debris – fragments and pieces of damaged
satellites, spent rocket stages ,etc.
Sizes – from millimeters to meters
Estimated number: 3e5 (size>1cm), 2e4 (size > 5 cm)
“Kessler syndrome” (1978) – collision cascading of
space debris
No effective measures yet!
Fragments with size > 5 cm can be tracked from Earth
by means of radars and optical sensors
Smaller objects should be observed from orbit
We propose to use standard star trackers for
monitoring of space debris
CORONAS satellites
CORONAS-F
CORONAS-Photon
07-31-2001
Launch date
01-30-2009
12-06-2005
End of operation
11-30-2009
549 km
Apogee
562 km
501 km
Perigee
539 km
82,5°
Inclination
82,5°
Optical star trackers
Mount:
Dimensions: 45 × 25 × 13 cm
Weight: 5 kg
Power consumption: 3 W
Lens:
Focal length: 70 mm
Aperture: 1.8
Star tracker mount on CORONAS-Photon
CCD:
Dimensions: 512 × 512 pixels
Pixel size: 13.5 × 13.5 µm
Pixel angular size: 0.6 arcmin
Exposure time: 3 sec
CCD-matrix used in star trackers
Attitude control
Star tracker image (07-01-2009 00:01:04 UT)
Detection limit
 d 2   S eff
1 I sun
   2
Nd  
  d  
2 2
4

  L

 d  I sun  d 2    S eff 
16  Vrel  L
 L 
  
  
V
  rel 
d2
 400 [photons/p ixel]
L
L – the distance to the debris particle in km,
d – the size of particle in cm
Isun = 0.1 [W/cm2] - solar radiation flux,
ad = 0.1 - the debris particle albedo,
Seff = 16 [cm2] - effective area of the telescope entrance aperture,
Vrel = 1 [km/s] - the debris particle relative velocity,
w = 3e-4 [rad]- the CCD single pixel field of view,
 = 0.5 - the CCD quantum efficiency,
Debris examples
CORONAS-F: 85 debris tracks found (out of 2e4 images)
CORONAS-Photon: 490 debris tracks found (out of 8e4 images)
Stereo imaging
 
[n  h ]
r  
[n   n ]
r1 = 4 m
r2 = 5.5 m
Vrel = 0.7 m/s
A pair of CORONAS-F images taken on 11-10-2001 (08:42:40 UT)
3d-model
CORONAS-F, 11-10-2001 (08:42:40 UT)
3d-model
CORONAS-F, 02-05-2002 (20:47:58 UT)
Self-rotating objects
Frequency of rotation ≈ 680 rpm!
CORONAS-F, 04-03-2002 (10:20:55 UT)
Single channel
dim
d im  ( D  d )
CORONAS-Photon, 05-20-2009 (22:10:43 UT)
F
Dd
LF
L
d im
D = 4 cm – entrance aperture
F = 7 cm – focal length
d – size of a pacticle
dim – size of an image
L – distance to a particle
L ≈ 7 m (for a small particle)
Vrel ≈ 4 cm/s
Orbital elements of debris particles
Filename
Semi-major axis, km
Eccentricity
Inclination
020518_211018
6810.1
0.00814
82.57
020502_204758
6845.9
0.00463
82.48
011110_084240
6870.3
0.00292
82.49
020311_055921
6825.5
0.00376
82.47
020403_102055
6891.9
0.01172
82.77
020515_223442
6811.7
0.00838
82.56
020716_181546
6787.7
0.01523
82.55
based on CORONAS-F data
Possible improvements
Resolution enhancement:
• Increase focal length
• Increase aperture
• Increase stereoscopic base
Coordinated observations:
• Even greater stereoscopic base!
• More data
• Make a catalogue of debris
• Theoretical modeling
THANK YOU!
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