NASA Uses ThreadX RTOS in Mars Reconnaissance Orbiter Spacecraft

Express Logic, Inc., the worldwide leader in royalty-free real-time operating systems (RTOS), announced that its ThreadX RTOS has been used by NASA in its ongoing Mars Reconnaissance Orbiter (MRO) spacecraft. The MRO mission is to map the surface of Mars with high-resolution and infrared imaging sensors so scientists can gain a better understanding of the Red Planet, including its past or present ability to support any form of life. ThreadX was the RTOS selected to manage the cameras responsible for the unprecedented quality of image currently being collected.

Image collection is all part of the High Resolution Imaging Science Experiment (HiRISE) developed by Ball Aerospace Technologies Corp., the same design team responsible for NASA’s highly successful Deep Impact mission, which also used ThreadX. HiRISE provides images of the surface of Mars with much finer resolution and a higher level of contrast than ever before. Managed by the ThreadX RTOS, HiRISE application software controls the acquisition of images across a six-kilometer swath of 20,000 pixels at a time while the spacecraft sweeps over the surface of Mars. While traveling at a speed of 3,200 meters per second, image data is continuously collected using a Time Delay and Integration (TDI) method that matches ground velocity and maintains alignment with the surface of Mars. HiRISE software adds header information to the data, ensuring that image swaths can be reassembled and sends the data to the image storage system and subsequently back to Earth.

“The characteristics of ThreadX suited the demanding resource-constrained environment we needed,” notes Steve Tarr, head of the HiRISE team at Ball Aerospace.

Express Logic’s ThreadX RTOS manages all software aspects of image collection in the HiRISE system. HiRISE is integrated into an overall system that coordinates the spacecraft operation with image collection. For instance, HiRISE image acquisition is coordinated with a separate application that controls spacecraft thrusters. The thrusters position and orient the spacecraft so that the camera is pointing at the area that is to be photographed. As well as delivering a very high resolution image of the Mars surface, ThreadX manages application software that controls a CTX imager that takes a wider angle view of the same region and a CRISM multispectral imager that obtains near-infrared spectral images that helps identify Mars’ surface composition.

“Participating in these two highly successful NASA missions is something we’re very proud of,” commented William E. Lamie, president of Express Logic. “Such missions as Deep Impact and MRO require flawless performance or the entire mission is jeapordized. We’re proud that ThreadX has met the challenges of both missions, enabling NASA scientists to learn more about the universe we live in.”

About Express Logic
Headquartered in San Diego, CA, Express Logic offers the most advanced run-time solution for deeply embedded applications, including the popular ThreadX(R) RTOS, the high-performance NetX(TM) TCP/IP stack, the FileX(R) embedded MS-DOS compatible file system, and the USBX(TM) Host/Device USB protocol stack. All products from Express Logic include full source-code and have no run-time royalties. For more information about Express Logic solutions, call 1-888-THREADX or email inquires to

ThreadX and FileX are registered trademarks, and NetX, CANX, USBX, preemption-threshold, picokernel, UDP fast path technology, are trademarks of Express Logic, Inc.