Alsat-1, the first satellite launched in the international Disaster Monitoring Constellation led by SSTL, has finally completed its mission for the Algerian Space Agency (ASAL) having exceeded its original 5-year design lifetime by 50% to a remarkable 7 years and 9 months.



Launched in November 2002 into a 700km sun-synchronous orbit on board a Kosmos 3-M rocket from the Plesetsk Cosmodrome in Northern Russia, Alsat-1 was Algeria's first national satellite - as well as being the first Disaster Monitoring Constellation satellite, it was also the first SSTL spacecraft to carry SSTL's newly developed Slim 6 Line Scan Imager payload.




Continue reading "Algeria’s first satellite mission completed"

This summer, students Charles Cleminson, Teodora Ghiuvea, Calum Jones and Rhys Llewellyn from The Sixth Form College, Farnborough completed a project under the Engineering Education Scheme (EES) in collaboration with SSTL looking at ways to detect signals in space that offer a precursor to earthquakes. Their report was well received by their SSTL and EES mentors, who congratulated them during the award ceremony.



The EES provides students aged 16 and 17 with experience in engineering, science and technology in order to make informed decisions about their future education and career. Working with SSTL, the project aimed to discover a suitable combination of payloads that would successfully identify and monitor the proposed earthquake precursors through regular measurements on a global-scale using a satellite constellation.

According to their very professional end of project paper entitled “A study to examine the feasibility of a constellation of small satellites to detect Earthquake precursor signatures”, up to now we have data only from older missions that are not dedicated to earthquake detection.

The team found that the main failing of previous missions is the lack of continuous measurements, so that statistics could not be built based on data from previous missions. As such, the team proposed, in addition to finding a reliable short term earthquake precursor, their proposed mission should make statistical studies of space-borne precursors of strong earthquakes possible by continuous monitoring. In summary, this data should lead to improved knowledge of the physics behind earthquakes and hopefully save many lives.

The team reviewed a broad range of technologies for detecting earthquakes from correlation with lightning, infra-red emissions, particle precipitation to numerous methods for detecting ionospheric permutations. These were analysed based upon their “prediction capability”, a measure of their ability to answer the three main questions of the short term earthquake prediction: When? Where? How strong?

Their conclusion: that the global monitoring of short term earthquake precursors from space is possible, but that a satellite constellation is necessary if this information is to be used in practice for short-term earthquake prediction.

Aside from the scintillating (no pun intended) discussion of Earthquake detention from space, it was a golden opportunity for the EES scheme team to learn more about space and real world engineering in a commercial environment. SSTL project mentor Dave Sanderson put Space Blog in touch with two of the team members, Rhys and Teodora to talk about their experiences and their future career aspirations.



Continue reading "Education, Earthquakes and Engineering"

During the Farnborough Airshow, a contract was signed for the provision of the Passive Hydrogen MASER (PHM) atomic clocks that will provide an essential timekeeper reference for the navigation payloads that SSTL is building for the Galileo navigation system, a programme of and funded by the European Union.

The PHM atomic clocks will be provided by SELEX Galileo, a Finmeccanica Company, for installation on each of the 14 satellites in the Galileo system, under a contract of more than 30m Euros.

The Passive Hydrogen MASER is the most stable clock ever produced for space applications with a frequency stability better than 10-14 day, and is currently demonstrating outstanding performance on board the Galileo GIOVE-B satellite. It is used as reference timekeeper to measure distance and positions in navigation systems. Its stability is better than 0,00000036 seconds in one year, equivalent to 1 second every 3 million years.

Timing is fundamental to Galileo and is essential for all services. It is best illustrated in positioning calculations, where a timing deviation of 1ns could result in a positioning error of 30cm on Earth.


Continue reading "Super accurate atomic clocks for Galileo"

SSTL’s UK-DMC2 satellite has successfully completed pre-launch tests and is integrated with a Dnepr launch vehicle at the Baikonur Cosmodrome in readiness for launch on Wednesday, 29th July 2009 at 18:46 UTC, 19:46 BST.

The new satellite will be operated by subsidiary company DMCii to provide an enhanced imaging capability and operational service to the Disaster Monitoring Constellation (DMC). UK-DMC2 has a number of enhancements over previous DMC spacecraft contributing to SSTL’s continuing evolutionary design approach.

UK-DMC2 carries a higher resolution optical payload which will provide 22m ground sample distance (GSD) images, compared with 32m GSD on the four operational satellites currently in the constellation. The 22m imagery has twice the data density of the 32m imagery without loss of Signal to Noise Ratio (SNR) and maintains the ultra-wide 600+km swath.

The satellite carries two high-speed X-band transmitters that will both operate at 20Mbps or 80Mbps. This will enable the satellite to download images up to 10 times faster than previous DMC spacecraft. Storage capacity has increased from 1 to 1.5 GByte on the first generation of DMC spacecraft up to 12 GByte on UK-DMC2. These advancements, in combination with improved power generation and storage systems, will allow UK-DMC2 to rapidly map large areas such as Europe or other continents.

The advances in data throughput and power generation have enabled two new operational modes. Firstly, a near-real time imaging and downlink mode allows imagery acquired within a ~2000 km radius of a ground station to be downlinked within the same pass and, secondly, the implementation of a broadcast downlink mode that enables customers with a receive-only ground station to receive data directly from UK-DMC2.

These technology improvements not only make the satellite more flexible than previous designs, but also dramatically increase the operational imaging capacity by allowing the satellite to store and download much larger volumes of multi-spectral image data.

In practical terms, the increased imaging capacity means that the satellite has less “dead time”. By fully using the different modes available, this latest DMC satellite will be able to rapidly download significantly more image data than previously possible. The satellite does not need to wait until it has emptied the onboard storage before being re-tasked to acquire further images elsewhere.

As an example, DMCii annually provides coverage of the Amazon Basin. These coverage campaigns have taken 6 weeks to complete with two of the current DMC spacecraft. By comparison, UK-DMC2 on its own can cover the same area in just 11 days.

The 96kg UK-DMC2 satellite is based upon SSTL’s SSTL-100 small satellite platform, which uses solar cells integrated into the spacecraft’s surface to generate power. UK-DMC2 includes an additional deployable solar panel that will increase power generation by approximately 50%.

It's a busy time for both SSTL and DMCii as the new DMC satellites UK-DMC2 and Deimos-1, which were launched on the 29th July are commissioned and their imaging systems thoroughly tested and calibrated.

Just a week after launch, DMCii had already begun acquiring stunning satellite imagery from both satellites using the new 22m multi-spectral imaging payloads that they carry onboard. This would not have been possible without the new 22m multi-spectral imager that was developed by SSTL's Optical Payloads Group (OPG) in Sevenoaks, Kent. In a addition to the more obvious resolution increase it has over the previous 32m DMC imager, it includes a number of technological advances that improve the quality and calibration of the images DMCii receives.



This first image shows the states of Texas and Oklahoma, USA. The DMC satellites are specifically designed to image very large areas with rapid response and at regular intervals, as shown in this first multi-state image. The new satellites can image much larger areas in a single pass than the previous DMC satellites due to advances in onboard storage and high speed satellite downlinks to the Earth.



This is one of the first 11 images taken by Deimos-1, see the Deimos-1 gallery provided by the satellite owner Deimos Space for more.

Continue reading "New DMC satellites deliver stunning images"

This evening SSTL will celebrate the first anniversary of the Earth observation satellites Deimos-1 and UK-DMC2 that were launched in July last year onboard a Dnepr rocket from the Baikonur Cosmodrome in Kazakhstan. The two satellites were quickly commissioned and joined the Disaster Monitoring Constellation to deliver their first images in August just a week after launch.

Deimos-1 was the first Earth Observation satellite built by SSTL for Spanish company Deimos Imaging, who have been capturing fantastic imagery of the world during the year. The following image and many more can be viewed in their online gallery.


It has also been an eventful year for the SSTL's own UK-DMC2 satellite, which captured images of the Forest Fires in California and more recently the spread of the Gulf of Mexico Oil Slick last month.
Continue reading "A year in orbit for Deimos-1 and UK-DMC2"

At the Farnborough International Airshow last week, the UK signed a historic agreement with Russia leading the way to greater collaboration in space between the two nations. SSTL welcomes this great news, which promises to make it easier for the two nations to benefit from their respective strengths.

SSTL has had a long and successful collaboration with a variety of Russian organisations spanning 20 years, working with the UK and Moscow offices of Commercial Space Technologies (CST Ltd.) as representative and local partner. SSTL and CST have together been one of the major customers for Russian launch services. However, don't think it's a one way street - SSTL is also playing an integral role in the high resolution Kanopus Earth Observation constellation with its partner FSUE NPP VNIIEM.

Professor Sir Martin Sweeting OBE, Executive Chairman of SSTL, commented

We have built up a close relationship with our colleagues at CST and the Russian Space Agency over the last 20 years, successfully launching 21 satellites on-board Russian rockets over 11 launch campaigns. SSTL was the first customer and partner for the DNEPR launch vehicle, allowing Kosmotras to compete in the international market for launch services using this launcher and also the first customer for SSO services from Plesetsk on Cosmos LV. SSTL is extending this relationship into the future through significant participation in the Kanopus high resolution Earth Observation constellation with our partner FSUE NPP VNIIEM and the launch of three further satellites from Russia later this year. I hope that the signing of this MOU between UK Space Agency and the Russian Federal Space Agency will bring further commercial benefits to the space activities and space industries of both countries.

In October, SSTL will launch the NigeriaSat-2 and NigeriaSat-X satellites on behalf of the National Space Research and Development Agency (NASRDA) by a Dnepr launch vehicle from Yasny, Russia on 29th October 2010.

Orbital Sciences Corporation (Orbital) has ordered nine GPS patch antennas from SSTL for the Cygnus™ advanced manoeuvring spacecraft – for those who don’t recognise the name, this is one of the forthcoming unmanned resupply spacecraft for the International Space Station (ISS)!

Orbital is the prime contractor for this spacecraft – which is one of the first truly commercial missions to be conducted for NASA.


The Cygnus spacecraft is being developed by Orbital to demonstrate cargo delivery services under a NASA Commercial Orbital Transportation Services (COTS) agreement. In addition to the COTS development and demonstration program, Orbital will utilise the Cygnus to perform ISS resupply flights under the Commercial Resupply Service (CRS) contract. This NASA contract authorises eight missions between 2011 and 2015 carrying approximately 20,000 kg of cargo to the ISS, as well as disposal of ISS waste.

The coming together of the commercial space entrepreneurs and the world’s most established space agency is not the only story here. As you’d expect, flying cargo to the ISS has its challenges, not least of which is manoeuvring and docking with the space station and Cygnus in fact comprises a common service module and a pressurised cargo module.




For more information, visit the Cygnus Factsheet

SSTL manufactures the majority of its sub-systems used in its own and third party missions, they are available to order and have been used extensively on a range of small and larger third party missions. For more details, visit www.sstl.co.uk/divisions/systems-and-services/subsystems

SSTL has delivered eight S-Band patch antennas to COM DEV this month that will play a small part in the Canadian space company’s exciting M3MSat (Maritime Monitoring and Messaging Micro-satellite) mission.

The M3MSat (Maritime Monitoring and Messaging Micro-satellite) is a technology demonstration mission jointly funded and managed by Defence Research and Development Canada (DRDC) and the Canadian Space Agency (CSA). The microsatellite is being designed, built and launched by COMDEV for the Government of Canada to support Canadian sovereignty, security, safety and communications needs within the territorial and maritime regions of Canada and beyond.

M3MSat is designed to demonstrate the full capability of advanced space-based AIS (Automatic Identification System) technology developed by COM DEV. AIS signals are broadcast from the world’s major marine vessels for navigation and identification purposes, but they are currently only collected by other ships and land-based receivers within a severely limited 50 nautical mile range. COMDEV's unique AIS technology exceeds the performance of any other known system and the collection of these signals from space would enable an unprecedented global view of the world's shipping traffic – rather like air traffic control but for ships.

The new S-band antennas will allow M3MSat to communicate with groundstations, and the four GPS patch antennas will allow the satellite to receive GPS signals to determine their position in space. This latest delivery supplements two GPS patch antennas that SSTL shipped to COMDEV last year.


SSTL’s patch antennas are particularly cost effective, an attribute further strengthened by their low mass design. The patch antennas belong to a complete S-band communications suite for telecommand, telemetry, and payload downlink that also includes Isoflux quadrifilar helix antennas for different coverage requirements.


A secondary communications payload will be operated on M3MSat to demonstrate a range of low data rate applications that can support Canadian civil needs as well as commercial requirements. The micro-satellite is expected to be launched in 2010.

It’s been a few months since our blog about the Engineering Education Scheme (EES) The aim of the scheme is to provide students aged 16 and 17 with experience in engineering, science and technology in order to make informed decisions about their future education and career.

The students from Farnborough 6th Form College are investigating ways to detect signals in space that offer a precursor to earthquakes. In this respect, it also has something in common with the POISE space experiment that SSTL helped students to develop on behalf of the British National Space Centre (BNSC).



In January, despite the unusually heavy snow the students managed to attend a two day workshop at Surrey University. The team had done some broad research into the field, but still had not decided on which technology(s) would be most appropriate for detecting precursors to earthquakes.

Within the first day, they had decided on a combination of a topside sounder that would measure ion concentration in the ionosphere from above, and an infrared camera which has also shown some promising results for earthquake detection. The rest of the time, the team concentrated on building a half-scale model of a Disaster Monitoring Constellation type spacecraft to be used for display purposes.

SSTL’s David Sanderson has been visiting the team roughly every two weeks after work to provide supervision and mentoring. Their model is now certainly looking the part (see photo above) and the team is preparing their report for assessment and celebrations in April.

SSTL’s satellite imaging subsidiary DMCii has used its UK-DMC2 satellite to monitor the oil slick in the Gulf of Mexico.

Satellite imagery is being supplied to the National Oceanic and Atmospheric Administration (Noaa), and the US Geological Survey (USGS) following an activation of the International Charter : Space and Major Disasters.


UK-DMC2 and its five siblings in the Disaster Monitoring Constellation (DMC) of satellites are able to provide daily imaging of the oil slick if required, detecting changes in the spill and tracking changes in direction. Current reports indicate that the oil click is moving towards the Florida coastline, having already reached land and affected Louisiana fisheries.

The DMC satellites use specially designed SSTL imaging payloads to image the Earth at resolutions between 4m and 32m across an ultra-wide 600km-plus swath (width).
Continue reading "Gulf of Mexico oil slick captured by satellite"

Brazil’s National Institute for Space Research (INPE) has completed its August 2008-July 2009 detailed survey of deforestation by shallow cut throughout the Amazon region (INPE announcement). Its PRODES (Monitoring of the Brazilian Forest by Satellite) programme analyzed 400 images from Landsat, CBERS and the DMC Satellite Constellation to confirm that deforestation during the period was 7464 square kilometers, a reduction of 42% in comparison to 2007-2008. This is the lowest annual deforestation rate since INPE started systematic monitoring of the Amazon forest by satellite in 1988.

DMCii has worked with INPE to provide annual imaging of the whole Amazon Basin since 2005 to support this activity. By using multiple satellites, each capable of imaging a 650km wide swath of the forest canopy, DMCii is able to provide multi-spectral images of the entire area in 4-6 weeks. This provided INPE with valuable and timely information to help identify the extent of deforestation.

A significant decline in deforestation in the Amazon Basin has been observed since 2004. This is due in part to INPE’s new earth DETER system that detects deforestation in real time by fortnightly satellite imaging. This allows the supervisory board to take effective and prompt actions to combat illegal logging as it happens, rather than having to wait until after the damage is done.

Satellite capabilities play a crucial role in providing impartial information about deforestation in these large, inaccessible areas. The development of satellite constellations, pioneered by the DMC satellite constellation, has led to improved temporal and spatial resolution, enabling operational monitoring to support active and timely response to deforestation.

INPE announcement: www.inpe.br/ingles/news/news_dest117.php

Development of a new instrument that could use satellite navigation signals to determine sea-surface roughness, ice characteristics, or soil moisture content has received a boost from the Centre for Earth Observation Instrumentation (CEOI). The SSTL-led team will continue the development in a CEOI funded project. The CEOI is an initiative to develop the next generation of Earth observation instruments, funded by the Natural Environment Research Council (NERC) and Technology Strategy Board (TSB).


The new project will continue the development of the instrument that exploits signals from the Global Navigation Satellite Systems (GNSS) satellites that are reflected from land, ice and ocean.


Continue reading "SSTL leads GNSS reflectometry prototype"

Flight proven satellite platforms from Surrey Satellite Technology US LLC (SST-US) have been selected by NASA's Rapid Spacecraft Development Office (RSDO) for inclusion in the third NASA Rapid Spacecraft Acquisition Catalog (Rapid III).

SST-US’ Chief Executive Officer, Dr. John Paffett stated

It is a privilege for SST-US to have been selected by NASA for inclusion in the Catalog. It is recognition of the company’s capabilities, expertise and heritage. We believe that the Catalog provides an efficient route for SST-US to provide rapid, low risk, cost effective satellite solutions to NASA and other Government Agencies and we look forward to delivering future mission opportunities.

Through this contractual framework SST-US will be able to engage with NASA and other Government Agencies for the rapid provision of low risk, cost effective satellite solutions based on the SSTL 150, 300 and 600 platforms.


Continue reading "SST-US platforms get NASA seal of approval"

SSTL’s Optical Payload Group is currently building two Dynamic Multi Star-field Simulators (DMSS) at its Sevenoaks facility that will be used to test star trackers that will be flown in space under simulated operating conditions here on Earth.

Star trackers are an essential subsystem in any satellite, providing information that allows the spacecraft's on board computer to determine its orientation or “pointing” at any point in time.

They work by taking an image of a region of the sky using a specially designed optical camera, and comparing successive images to determine how much the orientation of the satellite has drifted.

This information is then sent to an attitude control system that corrects for the drift by using on-board thrusters or other motion-generating devices to maintain the correct satellite pointing.

Any time a satellite is manoeuvred in orbit, the pointing information from star trackers is vital to the spacecraft’s control systems. For example, solar panels must be aligned to capture the maximum available light from the Sun, and communications antennae pointed towards the Earth.

Star trackers are now available that operate in autonomous modes. These units are able to dynamically monitor the star fields in orbit and provide correction information back to the satellite to counteract adverse platform manoeuvres, such as slews and spins, which is particularly useful in the early stage of mission operations or following a major system failure.

To test these units on the ground prior to launch, it is essential to present the star trackers with a dynamically varying star field. This is where the DMSS comes in.

Continue reading "Simulators prepare star trackers for spaceflight"

SSTL’s military space expert Dr. Stuart Eves has accepted a year’s secondment to the new Science and Technology Facilities Council (STFC) at the UK’s new Harwell facility to advise on space security. His principal responsibility will be as the authority on the Security and Resilience Unit (SRU) that will form part of the International Space Innovation Centre (ISIC).

Enough with the acronyms! ISIC is a joint venture between the UK Government and Industry, that is anticipated to evolve into a centre which supports both UK national requirements as well as international security-related space systems. The idea is to create a Hub of Innovation that will act as a seed-bed for innovation in the UK.

Stuart will also be expected to actively liaise with the newly formed UK Space Agency on space security matters in support of government policy making, since a close relationship between the policy and strategy aims of the agency and the executive elements at ISIC will clearly be essential.
Continue reading "Space security guru Stuart to advise government"

This week, an enormous cloud of volcanic ash is sweeping over Northern Europe, grounding aeroplanes and bringing the jet-setters to a standstill. One could be forgiven for taking it all for a hoax – there’s nothing for the common Earth dweller to see – but it’s bringing some businesses to a standstill as they struggle to make their meeting’s commitments.

The reason this ash cloud cannot be seen is that the ash cloud is moving relatively high in the atmosphere, although meteorologists say there are signs some dust is settling at lower levels, which could begin affecting the health of those with respiratory conditions such as asthma. However the risk to aircrafts is very real as reported in the excellent BBC News online article: Icelandic volcanic ash alert grounds UK flights



But what about satellite communications? Could the dust in the atmosphere affect the control of space missions, your Sky receiver or GPS? Pete Garner, SSTL’s Radio Frequency (RF) team leader commented:

Satellite comms could easily be affected, but the impact would depend primarily on weather conditions, which would determine how the volcanic ash is dispersed in the air.

Additionally - it would also depend upon the robustness of the comms links in question. I know personally that my Sky signal degrades or even drops out periodically if there is heavy rain in our area and the volcanic ash could cause similar problems as the density and composition of the ash cloud would reduce the link margin and therefore affect the quality of any transmitted signals.

SSTL tracks and controls many satellites from its Guildford-based ground station, but Pete explained that their systems are designed to cope with environmental factors – even if no-one expects clouds of volcanic ash over the green hills of Surrey:

SSTL ensures its LEO [Low Earth Orbit] comms links are robust enough to cope with heavy rain in most cases by sizing the whole comms system appropriately for the mission including environmental factors. Making sure there is adequate additional margin in the link budget design is a key factor from the early stages of any mission to ensure SSTL can continually control the satellites and obtain the important image data when required.

In some cases there is also a level of redundancy. For example, Earth observation satellites such as Nigeria’s new NigeriaSat-2 satellite that is scheduled for launch in Q4 2010 have the facility to download images to multiple groundstations around the world. Some satellites can also be tracked and controlled from more than one groundstation when required.