The IRIS mission logo features a sun, a prism with a rainbow light spectrum coming from it, and on the bottom a list of mission partners. Image credit: LMSAL
Artist's concept of the Interface Region Imaging Spectrograph (IRIS) satellite in orbit. Robert Carvalho began his career at NASA's Ames Research Center, Moffett Field, Calif., interning as a computer engineer in 1993. Since then, he has worked on a variety of projects, including helping develop software to manage astronaut training and technologies to enable more affordable spaceflight missions. One of the most challenging tasks in his career – both mentally and emotionally – was supporting the investigation of the loss of space shuttle Columbia.
What is your role on the IRIS mission?
I have two related roles. I am one of two flight controllers for the IRIS mission. Once IRIS launches, I will control the spacecraft on a daily basis. I am also a Ground Data System engineer, helping design, develop and integrate the software tools that will enable me to perform Flight Controller tasks. I also spend time with the teams developing the other parts of the mission, which helps me to understand how the whole spacecraft and mission work.
Wow – you control the IRIS spacecraft? How?
Yes! I'm really looking forward to actually controlling a satellite in space for the first time. As a Flight Controller, each day I will receive a timeline of observations of our sun that the IRIS Science Team wants to conduct, and potentially other requests for activities to be performed from the spacecraft or mission operations teams. I will integrate those activities into a series of commands to be loaded onto the spacecraft and then executed by the spacecraft. During all of this, I will check the telemetry to make sure that the observatory performs as it should. The telemetry includes information about the temperatures on the spacecraft, the direction it is pointing, whether systems are functioning correctly, and information about the onboard computers. We also have automated tools to alert us if there is a problem on the spacecraft while we are not in the Mission Operations Center.
The Mission Operations Center – is that like the Mission Control Center used to support the astronauts and the International Space Station?
The IRIS Mission Operations Center is located at NASA's Ames Research Center, Moffett Field, Calif. It is smaller, but is functionally similar to the control center used for the space station. Both send commands and monitor telemetry. IRIS is significantly less complex than the space station, so it will not take as many people to keep an eye on its systems. On a normal day for IRIS, we will only have two people in the IRIS Mission Operation Center during the day, and we will not be there around the clock like they are for space station.
So what exactly on the spacecraft do you control? Can you maneuver it in space or change its orbit?
IRIS has no propulsion, so once it is in orbit, it will stay there for a long time (until atmospheric drag brings it down). However, part of our commands will be to instruct the spacecraft which direction to turn, so that the scientists can take images of different parts of the sun. As the flight controller, I will be commanding all systems, but most of the commands I send will be commands to the instrument: when to take a picture, duration of exposure, wavelength, etc.
Ground Data System…what is that?
The Ground Data System (GDS) is the tools used within the Mission Operations Center to support my job as flight controller.
Oh! Okay – now, would you tell me more about the Ground Data System software?
The Ground Data System (GDS) includes tools I use before commanding IRIS, to convert and merge all the requests, and then to verify that the commands are valid before sending them. It also includes tools to monitor the telemetry as it is sent from IRIS. However, much of the time, IRIS is not in contact with the Mission Operations Center and so it stores its data on-board until it is time to send it. Then the science data is sent to the Mission Operation Center as large files. The GDS also includes tools to process these files automatically, and make sure that the science data gets sent to the science team, while any alerts about the spacecraft health are sent to the operations team. We acquired some of the software tools commercially off the shelf, and NASA and Lockheed Martin developed some specifically for IRIS.
What special knowledge do you need for this work?
For the work as GDS engineer, I use software engineering and programming to develop and integrate the tools we are using. As the flight controller, I also need to know the special language for commanding the spacecraft, and have a good level of familiarity with all of the systems on the observatory. I have worked with the teams developing the flight software on the observatory to understand as much as I can about that. I have participated in tests with the spacecraft and the instrument to understand the behavior of them, as well as potential failure modes.
What made you want to work for NASA?
My father worked on the Space Shuttle Program and the International Space Station, so I have always wanted to work with (or in) space. I studied and really enjoyed all kinds of math and science throughout school. I also enjoyed (and still do) reading science fiction. Many of the technologies that we take for granted today started in science fiction. In high school, I completed a study about what would be needed for people living permanently on Mars.
What part of the job do you enjoy the most?
I have really enjoyed the opportunity to learn so many new things during my work at NASA, and then use that knowledge. I have had the opportunity to see some amazing things, and meet many interesting people. I am very excited to have the opportunity to work on my first space mission.
What about the IRIS mission is most exciting to you?
IRIS is an opportunity to learn things about the sun that it is not otherwise possible for us to learn from the ground. Since the sun drives everything in the solar system, it is important to understand as much about it as we can. I am looking forward to being part of a team that is learning new things about the sun, and the energy it provides to the solar system.
Understanding the interface between the photosphere and corona remains a fundamental challenge in solar and heliospheric science. The IRIS mission opens a window of discovery into this crucial region by tracing the flow of energy and plasma through the chromosphere and transition region into the corona using spectrometry and imaging. IRIS is designed to provide significant new information to increase our understanding of energy transport into the corona and solar wind and provide an archetype for all stellar atmospheres. The unique instrument capabilities, coupled with state of the art 3D modeling, will fill a large gap in our knowledge of this dynamic region of the solar atmosphere. The mission will extend the scientific output of existing heliophysics spacecraft that follow the effects of energy release processes from the sun to Earth.
For more information about NASA's IRIS mission, visit: http://www.nasa.gov/iris