December 15th, 2016 by Mary Morris
I’m currently writing from Hangar AE, where it all happened. While we wait to make contact with all of the CYGNSS satellites after launch, I’m going to attempt some coherent thoughts about the past few days.
You may already have been following what’s been going on since my last post, but I’ll give a brief summary from someone who experienced it more directly.
We tried to launch on Monday, but had to return to base after two aborts. It was frustrating to see weather-related violations go green as we turned to dealing with aircraft anomalies. Eventually, we had to abort on Monday morning due to an anomaly with the hydraulic pump associated with the release mechanism on the L-1011 aircraft. Even though we showed up excited and ready to rock and roll, things just didn’t go our way on Monday. One thing I’ve learned is that there is an unlimited amount of things that can go wrong. It’s very rare for things to go according to plan. Even though we had to abort, the flight team wasn’t too disappointed—this is how things usually go. Things didn’t go entirely smoothly after that, either. We ended up finding an issue with flight parameter data on Tuesday, delaying our next attempt until today, Thursday.
At 3 o’clock this morning I sat down at my console in the engineering backroom—the cheap, but more fun seats. Everyone “on console” has a headset that can be used to tune into many different communication channels. There is a whole channel dedicated for anomalies! We got there at 3 am because there is a whole binder full of steps to complete before we could launch. In addition to all of the audio we could tune into, there were many video feeds and displays of housekeeping data. Talk about information overload! It was easy to stay awake on a few hours of sleep with all of those stimuli in front of me. The adrenaline also helped.
While we watched the feeds, we would keep track of the housekeeping data to make sure everything looked okay. We also had a video feed from the chase plane to keep tabs on the rocket. I remember everyone being absolutely glued to their screens in nervous anticipation as we watched the video of the Pegasus XL rocket launch.
In the engineering backroom, I was joined with other engineers who were very excited to see CYGNSS launch so beautifully. Here is a photo of everyone while we watched the rocket launch:
The engineering backroom crew was excited about the CYGNSS launch finally happening.
After all of the headaches earlier in the week, it was bizarre how well everything went today. In a flash, all of the CYGNSS satellites were orbiting and the L-1011 aircraft returned safely. Here is a photo of me, which hopefully portrays how excited I was, even with just a few hours of sleep.
Happy to see CYGNSS satellites up in orbit, while watching the feeds in our back control room.
We’re also so happy for Prof. Ruf and the entire team that made CYGNSS happen. Immediately after we launched, Prof. Ruf was bombarded by interviewers who wanted his take on the success of the mission.
While we had some post-launch down time, before we could communicate with the spacecraft, a beaming Prof. Ruf is interviewed in Hangar AE after the CYGNSS satellites were deployed.
A few hours after launch, we were able to start communicating with the spacecraft, but I’ll save a separate blog post for that topic since it was absolutely fascinating. Stay tuned and go CYGNSS!
December 11th, 2016 by Mary Morris
I’ve just gotten back from the CYGNSS pre-launch reception. We were happy to get to this day, after countless hours of hard work. Now, we’re all just excited and nervous to see what happens when our baby CYGNSS satellites (Octuplets!) are born into the world. We can’t wait to see what science mysteries CYGNSS data will help us unlock.
If all goes according to plan, on Monday, Dec. 12, at 8:24 a.m. EST, the spacecraft will launch aboard Orbital ATK’s Pegasus XL rocket. The rocket will deploy from Stargazer, Orbital ATK’s L-1011 carrier aircraft, over the Atlantic Ocean. You can watch coverage of the launch on NASA TV. The L-1011 will begin to taxi at 7:11 AM, taking off at 7:26 AM. The launch window opens at 8:19 AM. Prof. Ruf and I had fun hanging out near the L-1011 on Saturday, and I think this photo gives you some idea of the size of the rocket and aircraft.
Prof. Ruf and I chat with the L-1011 aircraft and Pegasus XL rocket in the background. Photo credit: Aaron Ridley
Here is a photo of the chase plane, which will monitor the rocket visually, providing us with footage back in the control room:
The plane that will fly near the L-1011, getting us a visual on the rocket as it flies out to the launch area. Photo credit: Aaron Ridley
I have an early morning and long day ahead of me, so I’m going to sign off now. Stay tuned and go CYGNSS!
December 10th, 2016 by Mary Morris
You’re probably wondering why I’m down at NASA KSC so early before launch day. We’re not down here relaxing on the beach; the weekend before launch is packed with events. For example, just today, I participated in our CYGNSS Science Team meeting and two press events.
Earlier today, I kicked off our science team meeting by presenting the results from the last couple chapters of my dissertation.
Here I am, presenting my work at the CYGNSS science team meeting. Photo credit: EJ Olsen
The science team meeting is basically a mini symposium. It gives those involved with the project a chance to show their results, collaborate, and get feedback from others. An extended science team has grown from the original list of scientists and engineers that wrote the proposal. There are two main things that I have been pleasantly surprised by as I have worked on this project: 1) There are many institutions involved with CYGNSS, and 2) CYGNSS science applications are not limited to hurricane science.
Today, at the science team meeting, these two things were very apparent. NASA scientists are not the only ones interested in the success of CYGNSS. For example, a number of collaborators work at NOAA and the Naval Research Laboratory and these scientists are interested in figuring out how to use CYGNSS data to improve weather forecasts. Over the past few years, I have seen a number of presentations from CYGNSS team members from many different institutions that have shown that simulated CYGNSS data can positively impact the skill of weather models. It has been illuminating for me—someone who has never done any of this type of work—to see what types of experiments scientists choose to perform, and what questions they seek to answer. Many on the science team are excited about assimilating the on-orbit CYGNSS data for the first time during this upcoming year.
Another interesting aspect of CYGNSS that you may be surprised by is that CYGNSS data will have a wide range of applications outside of hurricane science. A number of scientists are looking into figuring out how to use CYGNSS data for other areas of interest: soil moisture, extratropical storms, and the Madden-Julian Oscillation are just a few out of many research topics that scientists are currently experimenting with now. The techniques used for CYGNSS are still relatively new, and it will be interesting to see how science applications develop after CYGNSS launches, with new on-orbit data.
There are always many things to learn at science team meetings. Here is a picture of the entire group that came down to Florida to participate in the science team meeting in person:
CYGNSS Science Team members get together to meet and discuss new findings, as well as prepare for the first year of science operations. Participants included: Nancy Baker, Charles Bussy-Virat, Matt Buchanan, Tim Butler, Kenny Carlsen, Juan Crespo, Maurizio di Bisceglie, Lilli Galdi, Jim Garrison, Joel Johnson, Stephen Katzberg, Mark Leidner, Xuanli Li, Sharan Majumdar, Darren McKague, Brian McNoldy, Mary Morris, Stephen Musko, Andrew O’Brien, Jeonghwan Park, Derek Posselt, Zhaoxia Pu, Aaron Ridley, Emily Riley, Chris Ruf, Kaitie Schoenfeldt, Bill Schreiner, Seubson Soisuvarn, Tianlin Wang, Xiaosu Xie, Valery Zavorotny (Some not pictured, as they participated remotely.) Photo credit: Aaron Ridley
In addition to attending the science team meeting, I was asked to participate in press events today. It was fascinating to see what types of questions that the press and other audiences had during these events. My communication skills had to stretch across a large range of audiences today. I started off the day talking about my work to the science team in a more technical way, and ended the day talking to reporters and more general audiences. CYGNSS continues to be a once-in-a-lifetime kind of experience for me.
Behind the scenes from a Facebook live event: my research advisor (and CYGNSS PI), Prof. Chris Ruf, and I talk about what we’re excited to see from CYGNSS after launch, with the aircraft and rocket carrying CYGNSS into orbit in the background. Photo credit: Aaron Ridley
CYGNSS Science Press Brief, From left to right: Sean Potter, Chris Ruf, Aaron Ridley, and me (Mary Morris). Photo credit: Frank Marsik
December 9th, 2016 by Mary Morris
My name is Mary Morris and I’m a Ph.D. candidate in the Climate and Space Sciences and Engineering department at the University of Michigan. My advisor, Prof. Chris Ruf, just so happens to be the principle investigator (PI) of the University of Michigan-led NASA Earth Venture class satellite mission, CYGNSS. CYGNSS consists of a constellation of eight satellites, scheduled to launch on December 12th. Soon! This mission will provide scientists with key hurricane ocean surface wind speed data, which we hypothesize will improve our understanding of how hurricanes form and develop. You can learn more about CYGNSS by reading earlier posts made by science team members on this blog section, or by going to nasa.gov/cygnss.
Since I have such a unique opportunity to be a CYGNSS science team member as a graduate student, I was asked to blog about my experiences in the days leading up to the launch. This has been a dream job for me and I’m excited to share my thoughts with you. In a few decades, if this blog still exists, I hope old-me will be able to look back at young-me and laugh at my wide-eyed, young scientist perspective recorded here for eternity.
So, why is working on the CYGNSS mission a dream graduate school gig? Well, I knew from a young-age that I wanted to study the weather, I just didn’t know the details of how to make a career out of my math and physics-based fascination of the atmosphere and Earth. Once I learned about remote sensing and satellite imagery, I was hooked. I knew I wanted to study more about remote sensing and eventually work on Earth science satellite missions. After a series of last minute applications to remote sensing-related research opportunities—applications that I thought were long shots—I ended up accepting Prof. Ruf’s research assistantship offer to join his remote sensing group as a Ph.D. student. The position turned out to be the graduate school jackpot: CYGNSS was selected for funding right as I started grad school. The timing could not have been better. I would get to see the inner workings of a satellite mission being developed throughout all of the design reviews and pre-launch data product development. Needless to say, it’s been an interesting ride. Since CYGNSS combines two of my passions—satellite observations and weather—it’s been a fun project to be a part of.
Graduate students are basically apprentices. If your ultimate goal is to be a scientist on Earth science satellite missions, being the graduate student working under a principal investigator of a NASA satellite mission is ideal. CYGNSS is my first satellite mission, but not my first hurricane-related research project. Here is a picture of me doing research as a part of the NASA HS3 mission (which, I also blogged about here!).
Here I am, downloading data from an aircraft instrument, HIRAD, after a science flight as a part of NASA’s HS3 mission.
I’m nearing the end of my graduate school career, and by working on both the HS3 and CYGNSS missions, I’ve gained a lot of great experience by working for and with the best engineers and scientists in our field. With the CYGNSS launch coinciding with the end of my graduate school journey, I can’t help but be a bit emotional at the end of one journey and the beginning of another.
Stay tuned for more updates throughout the weekend.
December 10th, 2015 by Brian McNoldy
Numerical weather prediction models can be run with CYGNSS data included before the satellites are even in space. This is the premise behind the Observing System Simulation Experiment, or OSSE. In an OSSE, simulated measurements from any observation platform (past, present, or future) can be assimilated into a model and their impact can then be evaluated by comparing forecasts made with and without those measurements. For an introduction to CYGNSS and how it works, please read this previous blog post.
Idealized flow chart of an OSSE.
In an OSSE, the “real world” is actually high-resolution, high-quality model output from a “nature run”. That nature run is the foundation from which all observations are simulated and against which all analyses and forecasts are verified. Since the observing characteristics of instruments are known, “synthetic data” from any existing or future observation platform can be interpolated from the nature run and assigned realistic errors. If you’re living in the nature run, those synthetic data would be what your instruments would measure… including radiosondes, satellites, aircraft, buoys, and yes, even ocean surface wind speed retrievals from CYGNSS. [Note that times, dates, and events associated with the nature run are arbitrary — they do not coincide with specific events in the real world.]
An example of synthetic CYGNSS wind speed data spanning a six hour period over the Atlantic Ocean. A hurricane can be seen north of the Lesser Antilles.
Then, the suite of observations are made available to a data assimilation (DA) system. While there are a variety of DA flavors, the basic idea is that all available observations are taken into consideration in an optimal and dynamically-consistent way to produce a best guess of the current state of the entire atmosphere. This is called the “analysis”.
Analysis of the surface wind speed (shaded) and surface pressure (lines) on August 5 at 0000 UTC. The data assimilation method used here was a 3-D variational analysis scheme called GSI. This includes all available CYGNSS data within +/- 3 hours of the analysis time, as well as many other conventional data types.
The analysis provides the initial state for a forecast model. The forecast model, which must not be the same model used to generate the nature run, is integrated out in time. A short-term forecast (e.g. 6 hours) is used as the “background”, or first guess, for the next cycle’s analysis. Typically, the further out a forecast is run, the more it deviates from reality due to model errors, observation errors, and chaos.
The forecast model is used to produce a “control run”, which is one that includes a fixed set of observations or has a particular model configuration. Any additional data or tweaks to the DA/model system would be used to generate different runs, or experiments (“what happens if we add this”, or “what happens if we change that”). The model run is verified against the nature run by calculating errors in the analyses and forecasts — remember, the nature run is the real world in an OSSE. Output from each of the experiments can be compared to the control run to test if the errors were reduced or increased. Ideally, the addition of a new observation type such as CYGNSS improves upon the control run, but it is not always so simple in practice.
The plots below show errors in peak surface wind speed, minimum central pressure, and track for a tropical cyclone in the nature run from a control run (black line) and a single experiment with realistic CYGNSS data (red line). All of the errors from twelve forecast cycles are averaged together at the analysis time (0 hour), at 6 hours, and so on out through 120 hours. This is only an example from a single experiment, but other experiments conducted by our team include varying the DA cycling frequency, introducing “perfect” CYGNSS data interpolated directly from the nature run, adding realistic directions to the wind speeds, and assimilating higher-resolution CYGNSS data.
Errors in peak surface wind (left), minimum central pressure (middle), and track (right) for the control run (black line) and an experiment in which realistic CYGNSS data were introduced (red line). Note that lower error is ‘up’ on the y-axis on the left panel.
Based on results from a single tropical cyclone in a single nature run, simulated CYGNSS surface wind speed data do seem to have a positive impact on both analyses and short-range forecasts of tropical cyclone intensity. However, the impact on tropical cyclone track is not very noticeable, likely due to the limited influence of surface wind speeds on the storm’s steering levels.
Now we wait (im)patiently for when real data get collected and assimilated into models!
–Brian is a Senior Research Associate at the University of Miami’s Rosenstiel School of Marine and Atmospheric Science, and also blogs about hurricanes for the Washington Post.