Hero Engineers and Scientists Preparing for MESSENGER Spacecraft Orbit of Mercury

 Posted by DrJeff on April 22nd, 2010

 Copyright 2010  |  About this blog


Mercury Northern Limb 3rd Flyby, September 2009


















Photo Caption: Stop what you are doing for a moment, just imagine the stark contrast between the surface of this world and the vacuum of space, and click on this photo for a Zoom. Be thankful on this 40th Earth Day for the veil of atmosphere above you, slender as it may be. NASA’s MESSENGER spacecraft took this image of Mercury’s northern horizon on September 29, 2009, during its third and final flyby of Mercury, as we were covering the event live via Twitter from Mission Control in Columbia, Maryland. This image captures portions of Mercury we had never before seen—it represents history in the making. I invite you to read more about this image at the MESSENGER mission gallery.


This post is a Teachable Moment in the News.


This is crossposted at the Space Tweep Society Blog HERE.


FLASH: We interrupt the rhythm of your daily lives to bring you news from beyond Earth, from a tiny robot determined to take the human race to an alien world. Many of you tuned in September 2009 when Blog on the Universe provided live coverage of the MESSENGER spacecraft’s flyby of Mercury, the last gravity assist needed to get the spacecraft on course for Mercury orbital insertion in March 2011. We are now less than 11 months from that historic first—a spacecraft in orbit around the mysterious inner-most planet of our Solar System. You might want to bookmark the countdown clock.


Since last September 29, 7 months of our lives have been filled with a new school year, passage of seasons, and the ebb and flow of over 200 days. Meanwhile, dutifully navigating through the harsh environment of space, our little spacecraft has been steadily gaining on its rendezvous with destiny on March 18, 2011, under the watchful eyes of its extended family back on Earth—the MESSENGER Team. For this team, those 200+ days were filled with assessing data already broadcast to Earth from MESSENGER’s 3 prior flybys of the planet, and preparing for orbital insertion and on-orbit operations.


These engineers and scientists are the current generation of explorers on the frontiers of human exploration, and ought to be held up to our children as heroes and role models in the age of high technology—and at a time when America needs to step to the plate in science and technology education if we are to compete in the 21st century (you might want to read my related essay at Huffington Post.) So meet these heroes and role models—the Core Team, the Science Team, the Instrument Team, the Engineering Team, and the Mission Operations Team. Have a conversation with your kids, or if you are a teacher, have a conversation with your class about this remarkable group of folks. And to really get up close and personal, read how cool operations engineer Ray Espiritu got from his dream in middle school to being part of the MESSENGER mission. Read highlights on the lives of other MESSENGER Team members using the button at the bottom of the Highlights Page.


So now for some really exciting news sent to the entire MESSENGER Team via email on April 18, 2010, by Eric J. Finnegan, MESSENGER Mission Systems Engineer. I have provided the text of Eric’s email without modification to give you a sense of the behind-the-scenes communication and spirit of teamwork that a group of folks like you and me is undertaking on behalf of humanity. We are now fully engaged in preparations for an encounter with another world—



Public Relations

This month, preparations for orbital operations came front and center, with a press release describing the extent of preparations the team is conducting, tactfully described by our Payload Operations Manager, Alice Berman.


It hasn’t taken long—the navigation and guidance and control teams have almost closed the gap on Mercury. Over the last month, the predicted trajectory of the satellite has been narrowed to within 1-sigma of the target. Through careful management of the solar array positions and body orientations, the predicted trajectory of the spacecraft is now less than 10 km off the b-plane aim point and less than one minute from the target arrival time needed for Mercury Orbit Insertion. The likelihood of future trajectory correction maneuvers is rapidly diminishing!

MOI Readiness

The operations and engineering teams continue to prepare for events before, during and after the Mercury Orbit Insertion maneuver. The team is considering all possible nominal and anomalous conditions to ensure a robust execution plan, thereby ensuring a successful Mercury insertion. The next milestone for the team will be a Fault Management Review, occurring on June 2. An independent team of reviewers will look over the teams preparation plans and provide any necessary recommendations to ensure successful execution of this mission critical event.

Orbital Operations Readiness

The engineering and operations teams have completed all of the detailed table top reviews covering the necessary flight operations for each of the spacecraft subsystems. Furthermore, all of the detailed discussion meetings between the mission operations team and the instrument engineers, to review the on-board and ground command procedures for orbital operations have been conducted. These series of meeting and reviews have resulted in a number of items that will need to be worked off over the next several months as the teams work towards the fall Orbital Readiness Review.

The science planning and mission operations teams completed the most recent week-in-the-life (WITL) test activity on 24 March. A team debriefing meeting was conducted to cover the activities and lessons learned from the five week exercise. This activity required the MESSENGER team to process two consecutive weeks of orbital operations in a real-time test-as-you-fly environment. The next WITL test activity will exercise four consecutive weeks of orbital operations. The kickoff meeting for this multi-week activity is scheduled for 21 April.

This month, the instrument scientists started the final verification activities for the planning functions of the MESSENGER Scibox software. on April 5, the latest configured version of the SciBox software was released allowing instrument scientists to start evaluation of the software-generated observation plan. Presentations of these observing plans by the instrument scientists to the cognizant Science Discipline Groups will commence at the end of April. In parallel with this activity, the operations and guidance and control teams are working their way through verification of the commanding functions of the Scibox software. Over 10 weeks of the 52 week orbital schedule have been processed by the G&C team using high fidelity dynamics simulations to ensure safe execution of the auto generated command sequences. The operations team has processed 5 weeks of orbital schedules though their command verification tools and vehicle state simulations, ensuring valid execution as well as identifying a few command efficiencies. Processing of the Scibox software generated command sequences will continue until all 52 weeks of scheduled science activities have been processed through the verification tools from both teams.

As a cumulative test of orbital readiness, the operations team kicked off planning activities for a full flight execution of orbital operations, to occur this summer. Current plans are to execute 1-2 weeks of orbital operations, in a cadence and manner that will be utilized during orbit. This activity will flight verify the end-to-end operations of the MESSENGER system.

There are many activities to complete before March 18, 2011, however all members of the MESSENGER team are now engaged and are working toward successful execution of orbital operations.


Eric J. Finnegan MESSENGER Mission Systems Engineer



We wish the best to this remarkable group of folks for the continued success of MESSENGER, and stay tuned for mission updates, and extensive live coverage of MESSENGER orbital insertion. And readers, I invite you to put your thoughts to ‘paper’ with a comment below:)


The National Center for Earth and Space Science Education oversees the MESSENGER Educator Fellowship Program and other MESSENGER education and public outreach activities, including the development of compendia of lessons on Solar System exploration and science, and programming for families at the Smithsonian’s National Air and Space Museum. Consider one of the Center’s programs for your community. Blog on the Universe is also one of the Center’s programs.



Photocredti: NASA


visit Store Galactica, supporting programs of the National Center for Earth and Space Science Education

Comments are closed.