# Presentation: 410170

## Agenda

***Agenda***

***Overview of the System***
*Mission*
*Spacecraft*
*Advanced Land Imager*
*Hyperion*
*Ground System*
*Other Technologies*
***Significant Changes to Testing since Delta CDR***
***Top Level Schedule***
***Action Items Status***
***Issues/Concerns***

## Mission Overview

***Mission Overview***

***Co-Fly with Landsat-7 sun-synchronous orbit at 705 Km***
***Descending nodal crossing time 10:01 a.m., inclined orbit @ 98.2 degrees***
***Launched from Vanderberg AFB on Delta 7320-10, co-manifested with SAC-C***
***Collect sufficient ALI, Hyperion, and AC imagery to meet Validation and Science needs***
***Total spacecraft mass 588 Kg***
***315 Watts orbit average power***
***28 VDC Bus distributed with conditioning performed at subsystem***
***Three Axis stabilized for inertial and nadir pointing***
***On-board Global Positioning System for on-board navigation and timing (GSFC)***
***X-Band Phase Array Antenna used for science downlink @ 105 Mbps***

## Landsat-7

**Less Than 1 Minute**

**185 km**

**36 km**

**7.7 km**

**Landsat Multispectral Images**
**(185 km @ 30 m)**

**705 km Altitude**

**AVIRIS Underflight**
**(10 km @ 20 m)**

**Multispectral Images**
**(36 km @ 30 m)**

**Hyperspectral Atmospheric Correction (185 km @ 125 / 250 m)**

**Grating-based Hyperspectral Images**
**(7.7 km @ 30 m)**

- EO-1

## Mission Overview(continued)

***Mission Overview****(continued)*

***S-Band command and telemetry with backup to transmit science data at 2 Mbps***
***Electronics is based on GSFC MIDEX architecture used on MAP mission***
***Independent safehold in ACE***
***GSFC Wideband Advanced Recorder Processor (WARP) with storage of 40 Gbits***
***1 year live required***
***Zero fault tolerance***

## Spacecraft Overview

## EO-1 Avionics Configuration

## EO-1 Spacecraft

## Current Configuration Photo

- EO-1 Satellite in Swales Cleanroom

## ALI Overview

## Key ALI Significant Characteristics

***Key ALI Significant Characteristics***

***Multispectral and Panchromatic, 10 bands, 0.4 to 2.5 um***
***30 m resolution (10 m Pan band)***
***36 Km swath width, Push-broom***
***Lightweight Silicon Carbide Optics***
***SNR 100-200, depending on band, 5% reflectance***
***High temperature focal plane, 220K***
***Solar, lunar, and lamp calibration***
***Zero Fault tolerant***
***Simple S/C mechanical, electrical, and thermal interfaces***

## ALI Flight Instrument

## Hyperion Overview

## Key Hyperion Significant Characteristics

***Key Hyperion Significant Characteristics***

***Hyperspectral, 220 bands, 0.4 to 2.5 um***
***30 m resolution***
***7.5 Km swath width***
***SNR ~60, depending on frequency***
***1 year life, 2 year goal***
***Aligned to be within the Panchromatic band of the inboard ALI Sensor Chip Assembly***
***Solar, lunar, and lamp calibration***
*Radiometric cross-characterization with the ALI before launch planned*
***Zero Fault tolerant***
***Simple S/C mechanical, electrical, and thermal interfaces***

## Hyperion FlightInstrument

***Hyperion Flight******Instrument***

## Technologies

## Atmospheric Corrector (AC)

***Atmospheric Corrector (AC)***

***Description Of Technology:***
- Earth imagery is degraded by atmospheric absorption and scattering. The EO-1 mission will provide the first space-based test of an AC for increasing the accuracy of surface reflectance estimates.
- The AC provides the following capabilities via a compact and simple bolt-on design for future Earth Science, land imaging missions:
*High spectral, moderate spatial resolution hyperspectral imager using a wedge filter technology*
*Spectral coverage of .85-1.5 um, bands are selected for optimal correction of high spatial resolution images.*
*Correction of surface imagery for atmospheric variability (primarily water vapor)*
***Validation:***
- Ground validation of AC data using selected areas of globe where little surface variation exists but atmospheric variability changes. Also comparison of AC data with radiosondes, and other satellite sounders.
***Benefits To Earth Science Mission:***
- The AC Instrument will provide significant improvements in generating accurate reflectance measurements for land imaging missions.
- The algorithms developed will enable more accurate measurement and classification of land resources and better predictive models for land management in the future.

***Status:***
- Flight module completed environmental testing and ready for integration on spacecraft.
***Commercial Sources/Partners:***
- GSFC/Resource21

## Technology Need: High rate, reliable RF communication subsystems

***Technology Need: High rate, reliable RF communication subsystems***

_**X-BAND PHASED ARRAY ANTENNA (XPAA) **_
***Description:***
- The X-band phased array antenna is composed of a flat grid of many radiating elements whose transmitted signals combine spatially to produce desired antenna directivity (gain)
*Avoids problems of deployable structures and moving parts *
*Lightweight, compact, supports high downlink (100’s Mbps) rates.*
*Allows simultaneous instrument collection and data downlink.*
***Validation:***
- The XPAA will be validated through measurement of bit error rate performance and effective ground station EIRP during science data downlinks over the lifetime of the mission.
***Benefits to future Earth Science Missions:***
- Future Earth Science missions will be extremely compact but will produce tera-bit daily data streams.  The Phased Array  antenna technology will enable:
*Lower cost, weight and higher performance science downlinks*
*Lower cost and size  ground stations*
*More flexible operations*

***Status:***
- Flight module integrated and tested successfully on spacecraft.
***Commercial Sources:***
- Boeing

## Technology Need:   Constellation Flying

***Technology Need:   Constellation Flying***

***Status:****** ***
- EFF software which includes JPL and GSFC algorithms has been completed. GSFC algorithm successfully integrated and tested on spacecraft. JPL algorithm will be tested on spacecraft in July.
***Commercial Sources:***
- LORAL Tensor - GPS Receiver
- EFF Algorithms  - GSFC, JPL, Autocon Software (Hammers Inc.)

***Description:***
- The enhanced formation flying (EFF) technology features flight software that is capable of autonomously planning, executing, and calibrating routine spacecraft maneuvers to maintain satellites in their respective constellations and formations.
***Validation:***
- Validation of EFF will include demonstrating on-board autonomous capability to fly over Landsat 7 ground track within a +/- 3km while maintaining within one minute separation while an image is collected.
***Benefit to Earth Science Missions:***
- The EFF technology enables many small, inexpensive spacecraft to fly in formation and gather concurrent science data in a “virtual platform.”
- This “virtual platform” concept lowers total mission risk, increases science data collection and adds considerable flexibility to future Earth and space science missions.

## Technology Need: Increase Instrument Payload Mass Fraction

***Description:***
- The LFSA is a lightweight photovoltaic(PV) solar array which uses thin film CuInSe2 solar cells and shaped memory hinges for deployment. Chief advantages of this technology are:
*Greater than 100Watt/kg specific energies compared to conventional Si/GaAs array which averages 20-40Watts/kg.*
*Simple shockless deployment mechanism eliminates the need for more complex mechanical solar array deployment systems.  Avoids harsh shock to delicate instruments.*
***Validation:     ***
- The LFSA deployment mechanism and power output will measured on-orbit to determine its ability to withstand long term exposure to radiation, thermal environment and degradation due to exposure to Atomic Oxygen.
***Benefits to future Earth Science Missions:***
- This technology provides much higher power to weight ratios (specific energy) which will enable future Earth Science missions to increase  science payload mass fraction.

***Status:***
- Flight unit fabrication completed and successfully passed functional and environmental testing.
- Integration with spacecraft set for June 17, 1999.
***Commercial Sources/Partners:***
- Lockheed Martin, Phillips Lab

***Technology Need: Increase Instrument Payload Mass Fraction***

## Technology Need: Increase Instrument Payload Mass Fraction

- Integration and test of flight unit on spacecraft completed in November 1998.
***Commercial Sources/Partners:***
- Primex, Glenn Research Center, GSFC

_**PULSE PLASMA THRUSTER (PPT)**_
***Description:***
- The Pulse Plasma Thruster is a small, self contained electromagnetic propulsion system which uses solid Teflon propellant to deliver high specific impulses (900-1200 sec), very low impulse bits (10-1000uN-s) at low  power. Advantages of this approach include:
*Ideal candidate for a low mass precision attitude control device. *
*Replacement of reaction control wheels and other momentum unloading devices.  Increase in science payload mass fraction.*
*Avoid safety and sloshing concerns for conventional liquid propellants.*
***Validation:     ***
- The PPT will be substituted (in place of a reaction wheel) during the later phase of the mission.  Validation will include:
*Demonstration of the PPT to provide precision pointing accuracy, response and stability.*
*Confirmation of benign plume and EMI effects.*
***Benefits to future Earth Science Missions:***
- This technology provides much higher power to weight ratios (specific energy) which will enable future Earth Science missions, allowing higher science payload mass fraction.

***Technology Need: Increase Instrument Payload Mass Fraction***

## Technology Need: Increase Instrument Payload Mass Fraction

***Description:***
- Carbon-Carbon is a special composite material that uses pure carbon for both the fiber and matrix. The NMP Earth Observing–1 mission will be the first use of this material in a primary structure, serving as both an advanced thermal radiator and a load bearing structure  Advantages of Carbon-Carbon include:
*High thermal conductivity including through thickness;*
*Good strength and weight characteristics.*
***Validation: ***
- EO-1 will validate the Carbon-Carbon Radiator by replacing one of six aluminum 22” x 27” panels with one constructed using the C-C composite materials. Mechanical and thermal properties of the panels will be measured and trended during environmental testing and on-orbit to validate its operation for future Earth and space science missions.
***Benefits to Future Earth Science Missions:***
- This technology offers significant weight reductions over conventional aluminum structures allowing increased science payload mass fractions for Earth Science Missions.  Higher thermal conductivity of C-C allows for more space-efficient radiator designs.

***Technology Need: Increase Instrument Payload Mass Fraction***

***Status:***
- Panels successfully fabricated and meet required EO-1 structural requirements. Panels  have completed environmental tests and were delivered to spacecraft.
***Commercial Sources/Partners:***
- CSRP/Lockheed Martin

## Technology Enablers

_**WIDEBAND ADVANCED RECORDER/PROCESSOR (WARP**__**)**_

***Technology Enablers***

***Status:***
- WARP in final phases of environmental testing. Has been previously integrated with spacecraft. Final delivery set for June 10, 1999.
***Potential Commercial Sources:***
- Litton Amecom

***Description:***
- High Rate (up to 840Mbps capability), high density (48Gbit storage), low weight (less than 25.0 Kg) Solid State Recorder/Processor with X-band modulation capability.
- Utilizes advanced integrated integrated circuit  packaging (3D stacked memory devices) and “chip on board” bonding techniques to obtain extremely high density memory storage per board (24Gbits/memory card).
- Includes high capacity Mongoose V processor which can perform on-orbit data collection, compression and processing of land image scenes.
***Validation:***_** **_
- The WARP is a critical subsystem on the EO-1 mission and is required for mission success.
***Benefits to future Earth Science missions:***
- The WARP will validate a number of high density electronic board advanced packaging techniques and will provide the highest rate solid state recorder NASA has ever flown.
- Its basic architecture and underlying technologies will be required for future Earth imaging missions which need to collect, store and process high rate land imaging data.

## Ground System Overview

## EO-1 Mission Operations

***EO-1 Mission Operations***

## I&T Schedule Flow

## Significant Changes to Testing Since Delta-CDR

***Significant Changes to Testing Since ******Delta-CDR***

***The extra Thermal Balance/Thermal Vacuum and EMI/EMC tests before Hyperion delivery were deleted for schedule.***
***A radiance cross characterization test between the ALI and Hyperion, which was to be done at the system level, has been deleted in favor of a test at TRW.  This test will use the same hardware and personnel that calibrated the ALI.***