Main tasks 2 kHz distance measurements to 60 satellites Precision: 2.5 mm single shot;

Main tasks 2 kHz distance measurements to 60 satellites

Precision: 2.5 mm single shot; <<1 mm NPs Single photon detection / day and night Spin Parameter Determination

Multi-Static Laser ranging to space debris Preparing for the future:

ELT: European Laser Timing Experiment [ps] Quantum Cryptography via Satellites SLR to Nano-Satellites

IWF/ÖAW 1

Satellite Laser Ranging (SLR)

Refereed publications (since Jan 2013) Total: 15 (first author: 2) IRNNS: Quasi-Geostationary; 04-04-2014

Lead: Georg Kirchner

Members

Staff: H. Allmer, F. Koidl, R. Stieninger

four students for SLR measurements during part of nights

Cooperation within IWF

Gravity Field Group (Baur et al.):SLR and debris orbit determination

Key external collaboration

USA: ILRS/NASA; ESA; Czech Technical University; Korea Astronomy and Space Science Institute; Germany: BKG

IWF/ÖAW 2

Who are we?

SLR Global Performance 2013/Q3: LAGEOS NP RMSHitutsobashi University / Orbital Analysis

0.81.2

1.4 1.41.6 1.7

2.02.2

2.4 2.5 2.62.8 2.9

3.1 3.1 3.1

3.63.8 3.8 3.9

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NP

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S [

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>100 sats or >>200 passes/day

IWF/ÖAW 3

Graz Pass Switching: Day 295/2012:16:57-24:00 UTC20 LEO, 14 HEO: 34 Passes in 7.1 hours

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NOW: Tracking 60 satellites, with > 100 passes per day

Future: >100 satellites, with >200 passes per day

PLUS: Space Debris, Quantum Cryptography, Time Transfer, Nano-Sats …

Solution:

kHz SLR

Pass Switching …

≥1000 Pts/NP:about 0.2 mm

No NPs <100 pts

Envisat

IWF/ÖAW 4

Envisat: spin parameters from SLR Spins with 130 s, +36.7 ms per day “Flat” spin: stable spin axis

orientation Retros visible only in 50% of passes

(east in morning, west in evening)

Envisat Eight retros:

signatures visible

Used for precise spin period deter-mination

„Flat“ spin with stable orientation

In 13 sessions, each 2–3 h at early evening (objects visible):>200 passes of ~60 objects; up to >3000 km; low elevation

Graz Debris Laser Ranging 2013

IWF/ÖAW 5

Laser Debris Ranging 2013

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Range [km]

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[°]

RCS: < 1 m2

RCS: 1- 5 m2

RCS: 5-10 m2

RCS: >10 m2

Multistatic Experiment

SLR to Space Debris: Graz Results

IWF/ÖAW 6

One active station (Graz) fires laser pulse

Photons are reflected from satellite body

Several passive stations receive photons

⇨ Pseudo ranges added in single pass

⇨ POD of space debris significantly improved

Distances:

Graz – Wettzell: 400 kmGraz – Zimmerwald: 600 kmGraz – Herstmonceux:1200 km

WETTZELL detects Graz Photons 2013-09-24

007 / SL-16 R/B (23088); RCS: 11.2 m2

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Epoch Time [Seconds of Day 267-2013]

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Instrumental Development

IWF/ÖAW 7

C-SPAD200 µm

Sensicam CCD:Day

0.3 nm

0.3 nm

1 nm

ISIT: Night

M250 mm

M150 mm

600 – 900 nm

1064 nm

15 mm

30 mm

F=100 mmF=50 mm

SAP-500500 µm

IR-SPAD80 µm M4

50 mm

Spare …

New options

Þ 532 nm standard

Þ 532 nm debris

Þ 1064 nm debris

Þ 1030 nm debris

Þ All cameras here

Þ ISIT Box: Space for Quantum Detector (4 SPAD detectors)

Future tasks Different wavelengths/detectors: 532 /

1064 nm; 1030 nm; 808 nm; 710 nm All switch mirrors and filters: Remote

Control Fast switching between different tasks:

Routine ILRS SLR / debris / Quantum Cryptography etc.

Dual/Multi-color SLR possible

Tracking ILRS Satellites (increasing up to 100) HEO: 30 Galileo, 26 GLONASS,

8 IRNNS, 10 Compass; (GPS: 2018 +) >10 additional (mainly Earth observation)

satellites: ICESat-2, Jason-3, Sentinel-3… Spin determination Continuous SLR time series are essential for

most scientific results (POD, ITRF, EOPs, …)

Space Debris Optimize technology for debris ranging Single-Photon DART Bi- & multi-static debris ranging

Additional Experiments Time transfer (ACES/ELT) Quantum Cryptography with Chinese Sat SLR to several Nano-/Cube-Sats

8

Future Plans: 2015-2016

Planned: Jason-3 over California

Live Situation Display in GrazIWF/ÖAW

Thank you

IWF/ÖAW 9