profiling near-earth debris using picosatellites · orbital debris is estimated at 2x108 particles...
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Profiling near-Earth debris using Profiling near-Earth debris using picosatellitespicosatellites
❏ Can you do science with a shoebox-sized satellite?
❏ TRapping with Aerogel Prototype Satellite (TRAPSat)
❏ Design, build and launch a CubeSat capable of capturing and taking pictures of orbital debris, particles and dust in low earth orbit using Aerogel.
❏ Multidisciplinary, student lead,educational satellite development
'exploded' CAD cutaway of TRAPSat
Ryan Schrenk, Mikus Bormanis, Travis White, Angela Walters, Alex AntunesCapitol College (Laurel, MD)
Pro:
1) Inexpensive to build & launch
2) Low Risk
3) Allows Rapid Development
Con:
1)Small detectors only
2)Low weight
3)Low data rates
Best for:
prototyping detector techin-situ measurements
constellation & swarm measurements
Pico Feasibility for Science?
Aerogel for Debris and Dust Mapping
❏ Used successfully on multiple NASA missionsCaptured micrometeorites, comet dust/debris, and particulate matter
❏ Light weight❏ Transparent❏ Absorbs high velocity impacts❏ Works in vacuum❏ No power needed
NASA Stardust Aerogel sample image
Imaging through Aerogel in the Capitol lab
Tested-BalloonLaunch,April 2014
❏ >78,000 feet altitude❏Estimated -45 C❏ 180 pictures in 3 hours❏ 180MB data❏Captured 1 'grain' during descent!
“Raw” Aerogel slab imaging on ground
Orbital debris is estimated at 2x108 particles (>1cm), and 7x105 (>1mm).Density (>1mm) is roughly 10-4 particles per km3 (Weidemann and Vorsemann, 2012).
At 10 km/sec, a 10 x 10 cm LEO detector maps debris every 103 sec
With our 1mm dust mapper,we expect 0-2 detectable debris per orbit.
“Typical” circumsolar gas-to-dust ratios are 100:1, with typical gas densities of 5 atoms/cm3.At 10km/sec, a 10 x 10 cm detector will sweep out 5 x 104 dust/sec.But, most are <0.1um; large dust grains > 1um are our target of interest.Fractional abundances 1x10-6 for C and 10-8 - 10-9 for Al
2O
3, Si
3N
4 (Draine, 2003)
With a 1um dust mapper, we expect 0-1 detectable 1um dust per minute.
Utility: Orbital Debris vsCircumstellar Dust?
artist conception, TRAPSat in orbit
The fun thing about debris and dust is it is not evenly distributed.
Ubiquitous Swarm of Dust Mappers
Orbital debris tends to concentrate at the poles.collisional debris clusters in streams.Charged dust is pushed by solar wind.dust >1um is affected by gravity.Mariner 4 (1967) ran into an unmapped cloud of dust.LADEE specifically sampled dust near the lunar surface.
Autonomous bolt-on dust mappers returning frequency information-- size and velocity of large grains-- produces an aggregate data set.
ESA forecast on LEO orbital debris
Next- Pico science for near-Earth and Translunar Dust Mapping?
The “LunarCubes” movement seeks to use picosatellites past LEOCubes make good 'piggyback' packages on existing spacecraft; require no interfacing.Ergo, we suggest flying Dust Mappers as carry-on secondaries.
Precedent: United Launch Alliance discussed “Rideshare CubeSat Missions for Lunar Explorations” at the LunarCubes workshop, Nov 2013.
TRAPSat, 72,000 feet up, April 2014
Profiling near-Earth debris using Profiling near-Earth debris using picosatellitespicosatellites
Ryan Schrenk, Mikus Bormanis, Travis White, Angela Walters, Alex AntunesCapitol College (Laurel, MD)
The 'TrapSat' team at Capitol College adopts Aerogel to do in-orbit and potentially trans-lunar capture and observation of incident debris. We present early test results for this detector to measure the mass and distribution of ambient near-Earth and interplanetary debris. Expected debris includes both man-made orbital debris as well as micrometeorite particles. The theory is that depth images showing penetration of debris into the Aerogel capture mechanism (used successfully in comet capture missions) are transmitted to track the accumulation rate and estimated size of particles.
Astronautical EngineeringRyan Schrenk, Lead Engineer
Mikus Bormanis, Structural EngineerTravis White, Software Engineer
Trinity Wallace, Project AnalystEric Chubin, Payload Engineer
Nathan Weideman, EngineerWalter Diaz, Electrical EngineerCJ Giovingo, Integration Engineer
Phillip Frazier, Communications Engineer
artist conception, TRAPSat in orbit