Thomas A. Werne

DETECTION OF A FAINT FAST-MOVING NEAR-EARTH ASTEROID USING THE SYNTHETIC TRACKING TECHNIQUE

We report a detection of a faint near-Earth asteroid (NEA) using our synthetic tracking technique and the CHIMERA instrument on the Palomar 200 inch telescope. With an apparent magnitude of 23 (H = 29, assuming detection at 20 lunar distances), the asteroid was moving at 6o.32 day^(–1) and was detected at a signal-to-noise ratio (S/N) of 15 using 30 s of data taken at a 16.7 Hz frame rate. The detection was confirmed by a second observation 77 minutes later at the same S/N. Because of its high proper motion, the NEA moved 7 arcsec over the 30 s of observation. Synthetic tracking avoided image degradation due to trailing loss that affects conventional techniques relying on 30 s exposures; the trailing loss would have degraded the surface brightness of the NEA image on the CCD down to an approximate magnitude of 25 making the object undetectable. This detection was a result of our 12 hr blind search conducted on the Palomar 200 inch telescope over two nights, scanning twice over six (5o.3 × 0o.046) fields. Detecting only one asteroid is consistent with Harriss estimates for the distribution of the asteroid population, which was used to predict a detection of 1.2 NEAs in the H-magnitude range 28-31 for the two nights. The experimental design, data analysis methods, and algorithms are presented. We also demonstrate milliarcsecond-level astrometry using observations of two known bright asteroids on the same system with synthetic tracking. We conclude by discussing strategies for scheduling observations to detect and characterize small and fast-moving NEAs using the new technique.

The prototype development phase of the CubeSat On-board processing Validation Experiment

The Xilinx Virtex-5QV FPGA is a new radiation-hardened-by-design (RHBD) part that is targeted as the spaceborne processor for the Decadal Survey Aerosol-Cloud-Ecosystem (ACE) missions Multiangle SpectroPolarimetric Imager (MSPI) instrument12. A key technology development needed for MSPI is on-board processing (OBP) to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASAs ESTO3 AIST4 Program, JPL is demonstrating how signal data at 95 Mbytes/sec over 16 channels for each of the 9 multi-angle cameras can be reduced to 0.45 Mbytes/sec. This is done via a least-squares fitting algorithm implemented on the Virtex-5 FPGA operating in real-time on the raw video data stream [1]. Last year at this conference the results of a feasibility study between JPL and U. Michigan were presented in a paper titled, “A CubeSat Design to Validate the Virtex-5 FPGA for Spaceborne Image Processing.” Out of that study, a new task has been funded by NASAs ESTO ATI5 Program to integrate the MSPI OBP algorithm on the Virtex-5 FPGA as a payload to the University of Michigans M-Cubed CubeSat, manifest a launch opportunity, and gain on-orbit validation of this OBP platform to thereby advance the Technology Readiness Level (TRL) for MSPI and the ACE mission. This new task is called COVE (CubeSat On-board processing Validation Experiment) and is the topic of this paper. The COVE task is an 18-month effort to develop the flightready U. Michigan M-Cubed CubeSat with the integrated JPL OBP payload. The targeted completion date is September 2011. M-Cubeds primary payload is an OmniVision 2 MegaPixel CMOS camera that will take quality color images of the Earth from Low Earth Orbit (LEO) and save them to a Taskit Stamp9G20 microprocessor. This paper presents the prototype design and integration of the M-Cubed microprocessor system with the JPL payload that provides the image processing platform for on-orbit OBP validation. The high-level requirements and interface specifications for the delivery of the JPL FPGA-based payload hardware to the University of Michigan will be described. Finally, a recent decision regarding a launch opportunity for M-Cubed will be reported.

An evaluation of the Xilinx Virtex-4 FPGA for on-board processing in an advanced imaging system

The multi-angle spectro-polarimetric imager (MSPI) is an advanced camera system currently under development at JPL for possible future consideration on a satellite based Aerosol-Cloud-Environment (ACE) interaction study as outlined in the National Academies 2007 decadal survey. In an attempt to achieve necessary accuracy of the degree of linear polarization of better than 0.5%, the light in the optical system is subjected to a complex modulation designed to make the overall system robust against many instrumental artifacts that have plagued such measurements in the past. This scheme involves two photoelastic modulators that are beating in a carefully selected pattern against each other [1]. In order to properly sample this modulation pattern, each of the proposed nine cameras in the system needs to read out its imager array about 1000 times per second, resulting in two orders of magnitude more data than can typically be downlinked from the satellite. The onboard processing required to compress this data involves least-squares fits of Bessel functions to data from every pixel, effectively in real-time, thus requiring an on-board computing system with advanced data processing capabilities in excess of those commonly available for space flight

Real-time data processing for an advanced imaging system using the Xilinx Virtex-5 FPGA

The multi-angle spectro-polarimetric imager (MSPI) is an advanced camera system under development at JPL for possible future consideration on a satellite based Aerosol-Cloud-Environment (ACE) mission as defined in the National Academies 2007 Decadal Survey. The MSPI project consists of three phases: Ground-MSPI, Air-MSPI, and Space-MSPI. Ground-MSPI is a ground-based demonstration focused on characterizing the imager optics and performance. Air-MSPI will be an updated version of the ground system to be flown on an ER-2 aircraft. Lessons learned from the ground- and air-based demonstrations will be used in the design of the final satellite-based Space-MSPI instrument. In order to capture polarimetric data, the data collection algorithm oversamples the desired spatial resolution by a large factor. The actual polarimetric information can be efficiently extracted from this oversampled data. It has been proposed to do this extraction on the spacecraft for the purposes of reducing the total downlink data rate. As described in [1], the processing can be done in non-realtime on a Xilinx Virtex-4 FPGA. We have shown that this processing can be done in real-time on a Xilinx Virtex-5 FXT FPGA. Pseudo-random data simulating Ground-MSPI data stream is processed on the FPGA and the resulting polarimetric parameters are output using an Ethernet link to a host PC for verification. This demonstration is a stepping stone to an effective implementation for the Space-MSPI instrument.

A CubeSat design to validate the Virtex-5 FPGA for spaceborne image processing

The Earth Sciences Decadal Survey identifies a multiangle, multispectral, high-accuracy polarization imager as one requirement for the Aerosol-Cloud-Ecosystem (ACE) mission. JPL has been developing a Multiangle SpectroPolarimetric Imager (MSPI) as a candidate to fill this need. A key technology development needed for MSPI is on-board signal processing to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASAs Advanced Information Systems Technology (AIST) Program, JPL is solving the real-time data processing requirements to demonstrate, for the first time, how signal data at 95 Mbytes/sec over 16-channels for each of the 9 multiangle cameras in the spaceborne instrument can be reduced on-board to 0.45 Mbytes/sec. This will produce the intensity and polarization data needed to characterize aerosol and cloud microphysical properties. Using the Xilinx Virtex-5 FPGA platform, a polarimetric processing least-squares fitting algorithm is under development to meet MSPIs on-board processing (OBP) requirements. The Virtex-5 FPGA is not yet space-flight qualified; however, an in-flight validation of this technology on a pre-cursor CubeSat mission is valuable toward advancing the technology readiness level for MSPI and the ACE mission. 1,2

A constellation of SmallSats with synthetic tracking cameras to search for 90% of potentially hazardous near-Earth objects

We present a new space mission concept that is capable of finding, detecting, and tracking 90% of near-Earth objects (NEO) with H magnitude of

Implementing Legacy-C Algorithms in FPGA Co-Processors for Performance Accelerated Smart Payloads

\rm H\leq22

Validation of real-time data processing for the Ground and Air-MSPI systems

(i.e.,

MarCO: Interplanetary Mission Development on a CubeSat Scale

\sim

Command and data handling system for the Panchromatic Fourier Transform Spectrometer

140 m in size) that are potentially hazardous to the Earth. The new mission concept relies on two emerging technologies: the technique of synthetic tracking and the new generation of small and capable interplanetary spacecraft. Synthetic tracking is a technique that de-streaks asteroid images by taking multiple fast exposures. With synthetic tracking, an 800 sec observation with a 10 cm telescope in space can detect a moving object with apparent magnitude of 20.5 without losing sensitivity from streaking. We refer to NEOs with a minimum orbit intersection distance of