AstroVision Australia Ltd
Suite 9
2 Short Street
Double Bay
NSW 2028
Australia

url: http://www.astrovisionaustralia.com

Shubber Ali: Managing Director
Frank Williams: Chief Engineer
David Wright: Government Relations
Mitchell Burnside Clapp: Chief Technologist
Jim Styles: Sales/Marketing Consultant, WeatherMaxx

Incorporated in 2003, AstroVision Australia is a public unlisted company based in Sydney. Over the last year it has been familiarising Federal and State Government departments and research organisations on the potential uses of high speed imaging from cameras, infrared sensors, multispectral instruments and lightning detectors in Geostationary orbit.

Australia and other countries in this region are currently critically dependent for weather observations on one 11-years-old, partially disabled US geostationary imaging satellite with obsolete instrumentation, operated on lease from the American National Oceanic and Atmospheric Administration (NOAA). Called GOES-9 (GOES stands for Geostationary Operational Environmental Satellite), it has only a limited remaining life. Sudden failure of GOES-9 would place our region in a precarious position, affecting a wide range of industries and economies.

A Geostationary satellite, which orbits at the same speed as the Earth's rotation, would provide continuous coverage 24 hours a day, seven days a week from a fixed location high above the Earth, allowing cloud weather patterns and cyclones to be monitored continuously. Movements of ships, ocean temperatures, emissions of volcanic ash, growth of pastures and locations of lightning strikes causing bushfires are among many terrestrial and oceanographic observations that would be greatly enhanced through the satellite.

Advanced instrumentation, derived from equipment developed primarily for NASA interplanetary missions, will provide much more frequent observations than is possible with present day equipment. Australia has been chosen as the headquarters for AstroVision because of an obvious gap in modern geostationary satellite coverage for the Asia-Pacific.

The AstroVision 24 hour satellite coverage will be distinct from, and complementary to, that offered by rapidly-orbiting Low Earth Orbit (LEO) imaging satellites. LEOs give coverage for, at best, 15 minutes at a time once a day before disappearing over the horizon. The business model allows the total annual cost to be shared between a number of different government departments, research bodies, private clients and users across the Asia-Pacific region.

Technology

AstroVision's system architecture consists of:

• A geostationary imaging satellite orbiting at 36,000km above the equator. The orbit speed matches the speed of the Earth's rotation so the satellite is able to continuously image the same areas. The satellite carries seven sensors that collect land, ocean and atmospheric imagery, and,
• A ground system that controls the satellite and receives, processes and archives the imagery. This includes electronic cataloguing and distribution capabilities.

The AstroVision system is based on mature space heritage hardware and technology, one of the keys to the low cost, high reliability of the system. The sensors are derivatives of those developed and flown initially for interplanetary missions and planetary observation by NASA, which place a high premium on sensors being lightweight, with high reliability and low power requirements. This makes for smaller payloads, with smaller satellites to carry them, and results in significantly lower costs than traditional satellite projects.

The AstroVision satellites are less than half the size and mass of typical geostationary satellites. The satellites are 3-axis stabilized, using star trackers, similar to those in deep space and planetary missions, to meet the stringent pointing requirements of the satellite's sensors. This is necessary to avoid smearing of the images being sent back to earth.

The positioning of the satellite in geostationary orbit will be at or near 130° East Longitude and will provide 24 hour continuous coverage of the region from India to mid Pacific (west of Hawaii). The planned launch date for the satellite is in 2007 and the nominal life of the satellite is at least 9 years. The contract for the satellite bus has already been put to tender, and Ball Aerospace (Colorado, USA) was selected by AVII as the favoured entity for satellite construction and sensor integration. Ball has an established history in satellite construction with particular experience with imagery systems.

Three US patents (with numerous others in process) have been granted and issued to protect the system designed by AstroVision.

Cameras and Sensors

There will be seven separate sensors on board the first satellite: one wide field, two narrow field, one low light, one multi-spectral, one lightning mapper, and one thermal infrared. This combination of sensors will enable the provision of real-time imagery of not only the full Earth disk, but also higher resolution imagery of any significant events happening across the Asia-Pacific region, and a range of secondary applications created by the fusion of these data streams in different combinations.

The Wide Field Camera (WFC), capable of showing the Earth's full disk at 2.75 kilometre resolution, is actually composed of three cameras, each one providing one of the three standard red, green and blue colours that make up the typical true-colour digital image. The WFC is aligned with the spacecraft's nadir-pointing axis, directed toward the Earth's centre. The WFC will be fixed to the satellite body and will be pointed by pointing the satellite itself. The field of view of the WFC is sufficiently large to view the entire Earth disk including most of the Earth's atmosphere, while accommodating motions of the satellite bus. The WFC provides context for the Narrow Field Cameras for significant events.

There are two separate and independent Narrow Field Cameras (NFCs) capable of providing 250 metre resolution over a field of view of approximately 1,000 x 1,000 km for an instantaneous image of one million square kilometres every second. As with the WFC, each of these is made up of the three individual red, green and blue cameras. The two NFC sensors/camera sets are independently mounted on steerable platforms on the satellite bus, allowing use of the two cameras to provide high-resolution imagery of two independent significant events on the Earth's surface or atmosphere at the same time. These will provide local weather in all metropolitan markets in the region updated at least every minute.

The Low Light Camera (LLC) will also have the same field of view as the NFCs, is independently pointable, and take up to 1 frame a second. Used to observe light sources and events on the night side, the low light capabilities of this sensor will provide pictures of bright night-side events and under the right conditions and pictures of cloud cover at night using only moonlight for illumination.

The Multi-Spectral Camera (MSC) is made up of a Low Light Camera giving enough light-gathering capability to observe 10 separate frequencies of light at up to one frame a second and with the same field of view and resolution as the NFC. The MSC is independently steerable and allows observation in near-infrared and near-ultraviolet frequencies as well as the more common visually observable red, green and blue. Chlorophyll and volcanic ash are examples of ongoing processes that the MSC will be able to sense.

The Lightning Mapper Sensor (LMS) will be able to measure total lightning over much of the footprint of the satellite with a spatial resolution of 8 km per pixel and a temporal resolution (refresh) of two milliseconds. This will observe total lightning as well as turbulence within clouds and storms that will initially be used for severe storm tracking, fire prediction, and airline safety.

The Thermal Infrared (TIR) sensor will be able to measure temperatures to within one degree celsius with a spatial resolution as good as 4.5 km using half-stepping techniques and temporal resolution of approximately 2 seconds. The TIR observes the vertical evolution of clouds and storms, a means to monitor clouds at night, and surface temperatures of land and water where there are few or no clouds. The TIR can supply live temperature mapping relevant to energy demand and energy forecasting.

The combination of these seven sensors gives real time imagery of not only the full Earth disk but also high-resolution imagery of any significant events happening on the Earth within the footprint of the satellite. It also provides a range of secondary applications created by the fusion of the data streams in different combinations.

The differences between the technologies available today versus the AstroVision technology can be summarized as follows:

Operations

When an event occurs on or near the surface of the Earth, the event effects will arrive at the suite of sensors one-eighth of a second later - at the speed of light. The event will be recorded by the relevant sensor and transmitted from the satellite to an Earth station located in Australia, either one owned and operated by AstroVision, through one of AstroVision's partners/subcontractors or a customer's site licensed to receive the encrypted AstroVision data stream. On average, the entire process will take less than one second.

AstroVision's ground station will monitor the satellite in orbit and command the satellite to ensure proper orbit maintenance and the appropriate communications links are maintained. AstroVision plans to also transmit commands to the sensor on board the satellite providing the longitude and latitude of areas to be imaged in sequence. This latter function involves receiving, prioritising and uplinking the image requests received from AstroVision's direct customers and regional distributors.

Data Handling

Upon arrival at the Earth station, the data will be processed in real-time through our planned supercomputing facility. This Australia-based facility is anticipated to be one of the fastest supercomputers on the planet. Simultaneously passed to our storage network and downstream to our customers for distribution to fixed and mobile subscribers or direct to a remote client location. In addition, value-added services will be provided to specific customer data sets per contract, and the resulting products will be distributed in the most efficient method for use of the data (e.g. an alert service for bush fire detection providing exact GPS coordinates of a new fire event).

The technology developed by Horizon known as "Horizon TV" may also have the potential to provide an important delivery platform for some data and applications.

Data Storage

AstroVision intends to select and partner with an Australian university in a mutually beneficial arrangement. Data will be transferred to the university, which will maintain the permanent archive. The university will become a global centre of excellence for advanced meteorological and imagery processing and research, generate entirely new fields of research and grants for that research, and will draw the best and brightest information technology and space science students worldwide to its programs.

In addition to reducing/eliminating storage costs associated with the archive, AstroVision will benefit in two primary ways. Firstly, by agreement with the university, any new algorithms developed that have commercial potential will inure to the commercial benefit of AstroVision, with shared royalties paid back to the university. Secondly AstroVision expects a constant source of future engineering talent to draw upon from the graduates of the university's programmes driven by our data, algorithm development and research. AstroVision has initiated discussions with leading Australian universities to develop the selection criteria we will use for locating the archive.

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