octavian cristea 1 , paul dolea 1 , vlad turcu 2 , radu danescu 3

Octavian CRISTEA1, Paul DOLEA1, Vlad TURCU2, Radu DANESCU3

Long base-line stereoscopic imager for close to Earth objects range measurements

1: BITNET CCSS, ROU2: Romanian Academy, Cluj Branch, ROU3: Technical University of Cluj-Napoca, ROU

2011 IAA Planetary Defense Conference, Bucharest, 09-12 May 2011

END of life on Earth

might come from the sky …

ARE YOU AWARE?

In a wide area search mission, a telescope collects frames of data on consecutive directions in order to find objects in its range of detection.

The probability to point a telescope having a field of view FoV = 10 x 10 to an unknown stationary target on the sky is N x (3 x 10-5), where N is the number of scanned directions.

This probability becomes even smaller in the case of a fast moving (close to Earth) object with unknown orbital parameters.

The purpose of this project is to explore the ability of a very wide FoV stereoscopic imager to detect fast moving objects.

STEREOSCOPIC IMAGER PROJECT DEVELOPMENT MILESTONES

Robotic Long Baseline Wide FOV Stereoscopic Imager for up to LEO/MEO orbits (LEOSCOPE-1). Proof of concept: 2011

Robotic Long Baseline “All Azimuth” Stereoscopic Imager for up to LEO/MEO orbits – 201?

(LEOSCOPE-3)

Robotic Pseudo-Stereoscopic Imager for HEO orbits – 201?

(HEOSCOPE)

Technology Development2012 (LEOSCOPE-2) SECURED FINANCING

Robotic Long Baseline Wide FOV Stereoscopic Imager for up to LEO/MEO orbits (LEOSCOPE-1)

Stereoscope setup. Wide FOV pair cameras take simultaneous consecutive photos of the sky. The stereoscope’s base-line is 37 Km, a compromise between simultaneous detection of low altitude objects from two locations and triangulation accuracy. Pair cameras synchronization is made through GPS.

Geometric calibration of the image is made by matching captured stars in the image with an astronomical catalogue of stars. The recovery of orbital depth is made by correlating matching feature points from pairs of simultaneous images.

Piggyback wide FOV camera, component of the stereoscopic imager

The telescopic GOTO equatorial mount is used for camera optical axis alignment and Earth rotation compensation.

LEOSCOPE-1 pair camera sites

Marisel (1150 m elevation)

Feleacu (750 m elevation)

GPS synchronization

The LEOSCOPE-1 camera

LENS:20 mm F/1.8 aspherical, 88.6 mm aperture, 94.5 degrees angle of view

Actual CCDArray: 4752 x 3168 pixels Image area: 22.3 mm x 14.9 mmA/D converter: 14 bits, uncooled(will be replaced in 2011 by a research grade cooled CCD).

Setup (CCD + lens) specifications:Angle of view: 66 degreesLimiting angular resolution: 1 arcmin/pixelLimiting magnitude (uncooled CCD): approx. 8.85 at 13.1 sky magnitude and 5 s exposure.

LEOSCOPE-1: sample (unprocessed) image area at resolution3456 x 2304, 5 s exposure, without tracking

Fast moving Leonid meteor

LEOSCOPE-1: sample (unprocessed) image areas at small resolution

- 5 s exposure, without tracking -

AirplaneLeonid meteor

ISS over Cluj-NapocaNotice city light pollution Two LEO satellites

LEOSCOP-1: automatic objects classification is made before depth reconstruction through parallax

Examples of labeling distinct non-stationary objects in the images:

Red = airplaneBlue = condensation / irrelevant

Green = LEO satellite

STEREOSCOPIC IMAGER: SHORT TERM PLANS AND AKNOWLEDGEMENTS

• LEOSCOPE-1 development and range recovery experiments for LEO/MEO objects – partially supported through a grant from the Romanian Research Authority.

• Development of a third sensor for High Earth Orbits surveillance (if founding will be available).

• Participation to the NATO RTO SET 147 Deep Space Resident Space Object Tracking (HEOSS) experiment, in order to test the stereoscopic imager performances.

Thank you for your attention!octavian.cristea@bitnet.info