News Details | 19-Apr-2013

NTU’s X-SAT shows resilience in second year of operation

Homegrown satellite survives solar storms and 15 near misses; completing two key experiments and more than 3,000 operations

Soaring 800km above Earth at a speed of 7.5km per second, NTU’s X-SAT satellite begins its daily morning ritual by running self-diagnostic checks to ensure that everything is a go.

Suddenly, a large derelict satellite whizzes by, missing the X-SAT by a mere 16 metres. A direct collision at such high speeds would most likely leave the smaller X-SAT – the size of a mini fridge – broken and drifting in space.

Unfazed by the close encounter, Singapore’s first locally-built satellite continues with its mission of taking photos of the Earth’s environment.

Such a close encounter, which happened last July, is part and parcel of the many environmental risks which the X-SAT faces daily in outer space, while performing more than 3,000 operations in the last two years.

The X-SAT, a 105kg micro-satellite jointly developed by Nanyang Technological University (NTU) and DSO National Laboratories, was launched into space on 20 April 2011.

Tomorrow will mark X-SAT’s second anniversary in space, and NTU’s success in maintaining and operating a fully working satellite.

Despite enduring several solar storms and radiation particles which may had caused it to reboot each time and having 15 close shaves with large pieces of space debris, the X-SAT is more than ready for its third year of operation.

Director of NTU’s Satellite Research Centre Associate Professor Low Kay Soon said X-SAT had performed better than expected, with no visible signs of performance degradation.

“It has been performing as designed since day one in space and that signifies a built quality that is on par with international standards,” Prof Low said.

NTU Provost Professor Freddy Boey said X-SAT’s excellent condition and resilience are proof of the university’s strengths in applied research and engineering.

“NTU will continue pushing the frontiers of space,” Prof Boey said. “Together with strong industry partners such as ST Electronics, Lockheed Martin and German Aerospace Centre DLR, we will continue to be at the cutting edge of space and satellite technologies.”

“At the same time, we will continue to groom young talents under our unique undergraduate research programme where students get to design and build satellites under the guidance of our experienced faculty.”

NTU is the first university in Singapore which developed a satellite programme for undergraduates.

The X-SAT captures images and data which are used for environmental and earth monitoring, such as those of ocean red tides, oil pollution at sea and forest fires. Apart from performing its daily routine operations and remote sensing for environmental monitoring, the solar-powered X-SAT has also completed two important experiments.

One is a Global Positioning System joint project with The German Aerospace Centre (DLR) and the other is an NTU-designed reconfigurable Parallel Processing Unit (PPU). The PPU is a system which allows computer processing to be reconfigured so that it will continue functioning in outer space if any of its computing processors fail.

The PPU experiment has done very well so far with all its processors working, so the team hopes to push it even further by making it process satellite images in space, before beaming the photos back to Earth. Currently, all the raw data are downloaded to the ground station before being processed into photos.

Operating the satellite for two years has also given the team insight into how sensors, such as those for the sun and for magnetic waves, should be calibrated for use in space, says Prof Low.

Moving ahead, the X-SAT will continue to do remote sensing in its third year in space and is well on its way to successfully completing its designed three years of service.

Besides satellite images, the daily telemetry data of X-SAT is also a good source of information for the team to study degradation effects that the space environment has on the satellite.

Other NTU satellites in the works

In addition to operating the X-SAT, NTU’s Satellite Research Centre has also embarked on building the Singapore’s first weather satellite. The core team from the X-SAT program is also working on Singapore’s first commercial remote sensing satellite, TeLEOS-1.

The centre also runs Singapore’s pioneer undergraduate satellite programme that has involved engineering undergraduates from second year and above since 2009. Under this programme, students develop and build real satellites. Currently, the students have completed two pico-satellites (satellites that weigh around 1 kg) named VELOX-P and VELOX-PII which are awaiting launch.

The student teams are also working on another 4.5kg nano-satellite (nano-satellites typically weigh between a few kilogrammes and 20 kg) named VELOX-I, which is now undergoing its final stages of development and is on track to be completed this year. In NTU’s 10-year satellite road map, the university plans to develop at least four nano-satellites.



Media contact:
Lester Kok
Assistant Manager
Corporate Communications Office
Nanyang Technological University
Tel: 6790 6804

About Nanyang Technological University

A research-intensive public university, Nanyang Technological University (NTU) has 33,500 undergraduate and postgraduate students in the colleges of Engineering, Business, Science, and Humanities, Arts, & Social Sciences. It has a new medical school, the Lee Kong Chian School of Medicine, set up jointly with Imperial College London.

NTU is also home to world-class autonomous institutes – the National Institute of Education, S Rajaratnam School of International Studies, Earth Observatory of Singapore, and Singapore Centre on Environmental Life Sciences Engineering – and various leading research centres such as the Nanyang Environment & Water Research Institute (NEWRI), Energy Research Institute @ NTU (ERI@N) and the Institute on Asian Consumer Insight (ACI).

A fast-growing university with an international outlook, NTU is putting its global stamp on Five Peaks of Excellence: Sustainable Earth, Future Healthcare, New Media, New Silk Road, and Innovation Asia.

Besides the main Yunnan Garden campus, NTU also has a satellite campus in Singapore’s science and tech hub, one-north, and a third campus in Novena, Singapore’s medical district.

For more information, visit


Share Article