Mission Chronicles

My name is Tim Schmit, and I do research and help weather forecasters make the best use of the information available from environmental satellites. Specifically, I work with the Advanced Satellite Products Branch, which is part of the National Environmental Satellite, Data, and Information Service Center for Satellite Applications and Research. We are operated by NOAA (the National Oceanic and Atmospheric Administration) and located in Madison, Wisconsin. NOAA's National Environmental Satellite, Data, and Information Service operates the nation's civilian environmental (weather) satellites.

My interest in remote sensing started with my dad, who helped to design some of the first infrared sensors in the world. When I was in 7th grade, I decided to get a master's degree in meteorology from the University of Wisconsin in Madison. And that's exactly what I did—a bit later!

Sometimes I think I have the best job in the world. A favorite part of my job is when we are the first to check out a certain aspect of imagery from a new satellite. The initial images are always exciting, since they demonstrate the many components of the satellite that are working together.

NOAA keeps two satellites in geostationary orbit, each in a spot approximately 22,000 miles (about 36,000 km) from the Earth's equator. This position, which is stationary with respect to the ground below, allows the satellites, known as Geostationary Operational Environmental Satellites (GOES), to keep watch over the Western Hemisphere and parts of the Southern Hemisphere. But, before these satellites can be used operationally, they need satellite research meteorologists to make sure everything is working properly and to help convert the satellite data into meteorological information that can be used for important weather forecasts and warnings that can save lives.

I'm sure you have seen GOES "infrared" images on your local TV station, such as images of hurricanes approaching the U.S. The GOES are not only used for weather applications for the nation, but also for space weather, oceanography, hazards, climate monitoring, data collection, and search and rescue applications. These satellites are so important because they can monitor huge areas of our hemisphere that are not monitored in other ways. It's amazing how our natural environment can be monitored in such detail from a satellite located a tenth of the way to the moon!

The GOES series is developed by a joint National Aeronautics and Space Administration (NASA)-NOAA-Industry partnership, launched by NASA (with industry partners) and operated by NOAA.

The Next Generation

While the current generation of GOES gets the job done, the next generation will be far superior!

The GOES-R Series is the next generation of NOAA geostationary Earth observing systems. The Advanced Baseline Imager will provide much more information with higher resolution and faster coverage than the current system. With 60 times more data available, GOES-R will improve the monitoring of storms and natural hazards such has volcanic ash clouds or fires.

The most exciting part of the new imager will be the rapid-scan images. We will be able to see animations of events such as hurricanes, lake effect snows, convection, fires and more over various small regions of interest every one minute! We will be able to watch the phenomena almost as they happen, not just at the 15- or 30-minute intervals that we have today.

When I started working on GOES-R in 1999, the Advanced Baseline Imager had only eight proposed spectral bands, but a host of requirements from the National Weather Service. I was able to get eight more bands added to the instrument, so that the sensor is going to be much more capable and fulfill more of the National weather Service's needs. GOES-R is currently scheduled for launch in late 2015.

I am proud that we have been able to use our satellites to improve monitoring of hurricanes and other storms. I am proud of our whole group, including researchers from the government and universities, the private sector (to build the instruments and help send out the information), and, of course, NASA and NOAA to integrate and operate the satellites. I can't wait until the next generation offers even better monitoring!

For more information about the GOES and GOES-R, visit the following websites:

Past geostationary satellites:

Present (GOES):

Future (GOES-R):

Hi Everyone!

My name is Ben Toyoshima, and I've had the luck of Forrest Gump to get pretty good seats in the Mission Support Areas (MSA) for several NASA deep space missions. The MSA is the room where we actually "fly the spacecraft." That is, we work on the computers that are in direct communication with the spacecraft, via the giant Deep Space Network antennas here on Earth.

I am a Mission Controller, also known by network call sign "ACE." There is always an ACE on duty. Sometimes, he or she is the only Project Flight Team member in the MSA or—in the middle of the night, for example—maybe even on the whole Jet Propulsion Laboratory campus.

The most exciting times for an ACE are when the spacecraft is undergoing a major milestone "state change"—being launched, flying close to a target for observation (like an asteroid), being inserted into orbit (like around a planet), smashing part of itself into a something (like a comet), or landing on something (like Mars).

Those events are really important to the success of a mission, and usually all the Flight Team subsystem engineers are together in the MSA. Occasionally, an event also becomes a Big Deal with the media, dignitaries and our bosses right up to great-great-grandbosses at JPL and NASA headquarters.

But space is big, so most of the time for ACEs like me, we're just cruising. Getting to Mars, for instance, takes months. Getting to more distant planets takes years. Nonetheless, there is always routine stuff going on like calibrations, flight software upgrades, flight system maintenance, and rehearsals for the next big event. In general, only small state-changes are happening attended by only few of the subsystem engineers—no press, no dignitaries.

In those baseline cases, the ACE ensures that the ground resources that support all missions—like Deep Space Network antennas, receivers, demodulators, decoders, and transmission lines—are configured properly for the specific spacecraft being tracked, and that the data is getting into the MSA and databases OK.

The ACE makes the mouse click that sends data and instructional files to the spacecraft and then waits for the spacecraft's acknowledgement that it has received the data error free. The ACE watches for discrepancies between predicted and actual data. Through simulations and modeling, we have a pretty good idea what the spacecraft and its long-long communications link should look like and if there are discrepancies, it's the ACEs job to recognize, characterize, and triage them.

For instance the strength of the spacecraft's downlink carrier signal might be lower than expected. That might be caused by rain, or snow, or hail at the station. Or it could be because of an error in the predictions of where either the spacecraft antenna or the DSN antenna should point in order to acquire and follow the signal. Or maybe we've had a real hardware problem on-board.

The two largest state changes occur at launch when a flight system accelerates from zero to 17,000+ miles per hour and then when it transforms itself from a tightly packaged, encapsulated machine into a real spacecraft, with its communication antennas, solar panels and science instruments deployed. The complementary case is when, the spacecraft transforms from a very energetic flying body to one at rest on some extra-terrestrial body like a planet, moon, or comet. A LOT of energy is either imparted or dissipated from those machines in a very short time. That's scary. So we think a lot about all the things that can go wrong. We write contingency plans and rehearse them. We spend a lot of time and energy preparing.

So our job can be very exciting—nerve-wracking, actually, thinking about all the things that might go wrong. What if the rocket was slightly off course or a lander comes to rest upside down? After a major state change, there is a window of time during which we expect to hear from the spacecraft (called acquisition of signal, or AoS).

We rarely have AoS at the earliest possible time. So then we wait. The passing seconds and minutes feel longer and longer. And the MSA gets really quiet and tension mounts.

We knew the rover successfully shed all its speed, had touched down and was now bouncing on the surface of Mars. It did not just SPLAT! and break into a million pieces. We were bouncing on the surface of Mars really-really high, still trying to shed some of the energy the Delta rocket gave us months before during launch.

Finally, at rest, and intact enough to call home, with some telemetry we AoS'd and we were all very happy. And the real work of the mission could begin...

Every year in September, I visit the UK for three weeks to work with my colleagues from my time as a graduate student. Five years after graduating from the University of Southampton, I still have a great working relationship with my Ph.D. advisor and a number of other scientists in the UK. This three-week stint is like a magical mystery tour for me—the chance to do my own science, and a reminder of how being on the very cutting edge of any field can be both incredibly exciting and unbelievably frustrating.

For 49 weeks of the year I work at the Infrared Processing and Analysis Center (IPAC) at the California Institute of Technology. I split my time equally between the NASA Exoplanet Science Institute (NExScI), and NASA's Spitzer Space Telescope. I absolutely love my job. When working for NExScI I'm either organizing conferences and learning from the experts about the chances for life on distant worlds, or I'm touring the enormous Keck telescopes in Hawaii, or travelling across country to represent the Institute at scientific conferences. With Spitzer, I'm standing in front of a roomful of 7-year olds, telling them about the awesome grandeur of the Universe, or working with scientists to write their press releases on their groundbreaking results, or I'm writing a video podcast script to teach schoolchildren about how stars die. I'm astonishingly lucky to have such a varied and interesting job, and it's a rare day when I'm not excited to be making my way into work.

Having said all of that, there are some moments when I have a craving for my time as a grad student—to those halcyon days when I had nothing to do but my own (and my advisor's) research. Long weeks stretching out before me, where my only responsibility was to finish writing a program to model our latest theory, and the only emails I got were either from my advisor or from my friends telling me about social plans.

These three weeks in the UK are my annual journey back to that time. I'm lucky enough to work for an organization allows me to leave my usual duties, to sit in front of my laptop in my Ph.D. advisor's office and work with him on our own research again. Suddenly I find myself engaged in my own science, looking at the remains of ancient planetary systems around dying stars, millions of miles away. It's incredibly exciting to suddenly be back on that edge of discovery, looking at images of these stars that no one else has seen, making the plots and running the modeling code that will tell us about the make-up of these distant solar systems. Then about 2.5 weeks into this venture, we realize that the modeling code is telling us something unexpected, that we're going to have to revise our theory to account for the new findings, and the paper that we were planning to have written up and submitted for publication by the end of the month is probably going to take another six months to finish. It's at about that point that I start dreaming of easier times: organizing conferences, writing podcasts and enthusing young students about the birth of the Solar System.

It's with a feeling of relief that I arrive back in California to get stuck back into my usual routine again, but I'm very aware of how the annual time-out makes my day job far more satisfying. With a balance of science and education work for the majority of the time, plus the ability to turn back the clock for three weeks a year, I'm regularly reminded how much more I enjoy work now that I have so much daily variety. It's a valuable lesson that I hope to bear in mind throughout my career.

My name is Michele (pronounced mi-KAY-leh) Vallisneri, and I am a scientist at the Jet Propulsion Laboratory. I am part of a team working on a space mission called LISA, the Laser Interferometer Space Antenna. If we work really hard and we are very successful, the mission will be ready for launch ten years from now.

Why would I work on something that takes so long to bear fruit? Well, all good things take time. But I must say it is all Albert Einstein's fault. You see, in 1915 Einstein came up with a new explanation for the way gravity works--yes, that old question of why apples fall to the ground and why the planets orbit the Sun. Newton had solved this already in the seventeenth century, but there remained a few discrepancies with observations. More important, Newton's universal law of gravitation could not be squared with Einstein's special relativity, which explains how space and time are really a single entity ("spacetime"), and how different "observers" in motion with respect to each other can have different ideas of times and distances. It's fascinating stuff, but it needs more space than I have here. (Einstein Online is a web portal explaining more.)

All the universe a stage?

Anyway, in 1915 Einstein pointed out that spacetime is not just a big stage where "physics" happens, but it is an active player itself; it can bend and warp and undulate! Masses, especially big ones like the Sun, bend spacetime ever so slightly, and gravitational forces occur naturally because the planets and the apple try to move as straight as possible in spacetime--but have to curve, because spacetime itself is curved! (The fall of the apple can still be seen as a curve, not in space, but in spacetime.) And what about the undulations? When masses move around rapidly, like for instance two stars in a close binary system, they create outwardly propagating waves in spacetime-gravitational waves. You can imagine them as the waves created in a pond when you throw in a stone; except gravitational waves do not move out in circles, but in spheres, and they do not affect the surface of water, but the very fabric of spacetime.

Listening to the dark

If we could listen to these waves, we would learn a lot about the Universe, especially about its dark side, which we cannot observe with telescopes. This dark side is populated by heavy objects that nevertheless do not emit much light, such as the huge black holes at the centers of galaxies, millions to billions of times heavier than our Sun.

Since the 1960s, scientists have been trying to detect gravitational waves, but it's very hard, because when they cross the Earth, the waves create only minute perturbations. The best attempt so far is with the giant interferometric detectors such as LIGO (Laser Interferometer Gravitational Wave Observatory), which have "arms" of 2.5 miles to magnify these minute signals.

With LISA, we want to bring this quest to space, and create a gravitational-wave antenna consisting of three spacecraft positioned in a triangle, with arms of 3.1 million miles (thirteen times the distance from the Earth to the Moon). We want to go to space because it is so quiet and because you could not do something so big on the ground; also, a big antenna can measure the waves with the largest wavelengths (the distance between two peaks in the oscillations). There are many systems in the Universe that can emit such waves, so once LISA is up, we're sure to hear and learn a lot.

The nuts and bolts

So what's it like in our day-to-day work getting LISA ready? It takes many people with different talents, from the engineers who plan the spacecraft launch and trajectories, to the experimental physicists who are testing the optics, lasers, mirrors, and all the widgets that will make the instrument work. I am a theorist, so I am happier with pen, paper (and a computer) than around a lab. I work to prepare mathematical techniques and computer programs to analyze the LISA data, so that once it's in the sky and it starts making measurements, we'll know what we see. Is it a binary of black holes or neutron stars? How heavy are the components?

One aspect of this preparation can be especially fun. Together with many other LISA physicists around the world, we just finished playing a "mock data challenge." A group of us made a set of measurements, just like what we'd get from the real mission, and "hid" some gravitational waves in it. Another group then took the data and tried to get the waves out. There were many surprises! Some of us thought they had found a (fake) binary emitting on one side of the sky, but it was really on the opposite side. It's hard to do science in space, and that's why we must start so many years in advance; but the payoff will be great, and physicists always like a challenge.

See the LISA mission website.