Archive for January, 2018

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ICESat-2 Antarctic Traverse: A Successful Traverse, by our Travelin’ Band

January 12th, 2018 by Kelly Brunt

We smashed it.

Our team is back at South Pole Station after a highly successful 88S Traverse. We budgeted 16 to 19 days for the traverse, but we returned to station after just 15 days. Our science instrumentation and the vehicles performed with only minor hiccups, and in general, any problems that arose were solved quickly.

PistenBullys on traverse! Two tracked vehicles hauling the living quarters and equipment for the folks on the 88S Traverse. (Photo: Chad Seay)

The campaign by the numbers: 750 km (or 466 miles) of ground traverse; 15 days; 4 people; 2 PistenBullys; 4 corner cube reflector arrays; many snack, including an irrational number of Slim Jims; ~3 lbs of coffee; 1 giant tub of ice cream; and way too much CCR, Ozzy, and Styx.

But first – 4 days to get to our study area! To reach the southern extent of the ICESat-2 ground tracks at 88 degrees latitude, where we’ll take ground measurements to compare with future satellite data, we had to drive 220 km (137 miles) from the South Pole. We collected GPS elevation data along the way, in part to get ourselves up to speed with the day-to-day business of data collection and in part because there is very limited ground-based elevation data in this region.

The first 110 km (68 miles) of this was on the established, groomed, South Pole Traverse route, which had been driven three times this season as teams delivered fuel to South Pole Station. But after that, we were on our own…

The polar plateau, interrupted by PistenBully tracks. (photo: Kelly Brunt)

We turned left off of the South Pole Traverse route and began breaking new ground. After another 110 km, we were on the 88S line of latitude!

Almost instantly, we arrived at a point where Tom and I wanted to deploy an array of corner cube retroreflectors (CCRs), which are made of specialized glass that will strongly reflect the transmitted signal from ICESat-2. These points of strong reflection will be used to validate the pointing of ICESat-2.

The CCRs are insanely small, smaller than your pinky nail. Setting up the first array of 6 CCRs took about half a day, as we mounted the CCRs on the top of bamboo poles and then precisely located the position of the bamboo poles by occupying the site of each pole with a survey-quality GPS for 20 minutes. Since most of this was accomplished outside, you can imagine that this was a pretty cold morning. Ultimately, we deployed 4 CCR arrays along the 88S route.

A insanely small corner cube retroreflector, mounted on a bamboo pole (Photo: Tom Neumann)

With the exception of the areas associated with the CCR arrays (and yes, every time I say ‘CCR’, Tom sings a John Fogerty classic; it’s true even in his reading of this), the bulk of our days were consumed with driving. We averaged about 60 km (37 miles) per day, at a breakneck speed of about 9 km/hr (5.6 mph).

And as with any road trip, we consumed a lot of road snacks, including chips, jerky, and in the case of our mountaineer Forrest, many, many Slim Jims.

After about a week on the 88S line of latitude, we reached a point where we had collected our goal: 300 km (186 miles) of ground-based elevation data for direct comparison with ICESat-2 elevation data. Forrest fired up Ozzy’s ‘Mama, I’m Coming Home’ in his PistenBully and we made our second left turn, toward Pole.

The sled train headed south toward the Pole, and ultimately toward home (Photo: Chad Seay)

From 88S, we again traveled 220 km to traverse from our study area to Pole. We continued to collect data along this stretch, but our focus turned to the tired PistenBullys, which are 17 years old and not accustomed to two straight weeks of intense usage. Our incredible mechanic Chad kept an eye on these and helped to nurse them home.

We did so well, that I was overly conservative on consumption of really good coffee: I made Tom drink mediocre coffee for about a week, before I felt confident that the really good coffee would last the whole traverse. For this, Tom, I am eternally sorry.

Hey Eileen: Mama, I’m coming home.

-Kelly and Tom

Goddard Instrument Field Team (GIFT): In New Mexico, Land of Volcanoes

January 11th, 2018 by Jake Bleacher

On June 5, 2017, a convoy of vans and SUVs drove west from El Paso, Texas, and crossed into New Mexico, headed to a location about 20 miles southwest of Las Cruces. Leaving the pavement behind, we bumped along single-file on dirt roads, marking our way with a trail of GPS “breadcrumbs” and stopping occasionally to let the lagging vehicles catch up. Our destination: a geologist’s wonderland called the Potrillo volcanic field.

New Mexico is home to an impressive number and variety of volcanoes, spread over the state from top to bottom. Among them is the Potrillo volcanic field, a now-dormant region in the New Mexico portion of the Chihuahuan Desert. My team spent 10 days in June 2017 at Potrillo, visiting ancient craters and gently sloping shield volcanoes.

The Potrillo volcanic field. The volcanoes here are monogenetic, which means that when they were active, each one probably had a single eruption. These days, the Potrillo volcanoes are dormant. NASA Earth Observatory image by Jesse Allen.

Our team chose Potrillo because it combines the maar craters formed by explosive volcanism with the shield volcanoes formed by effusive volcanism. This makes it a perfect analog site for testing the kinds of instruments that future explorers might use to investigate volcanic areas on the Moon, Mars and other rocky planets or moons. We brought an array of instruments to map the topography of this terrain and to investigate the mineral composition and chemistry of the volcanic features here.

One of our destinations in the Potrillo volcanic field was the crater called Kilbourne Hole, shown in this fly-over footage taken by our unmanned aerial vehicle.  Music in this short video was provided by Killer Tracks. NASA/GSFC/UTEP.

I’m Jake Bleacher from NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and I led this trip. The group included planetary geologists from NASA Goddard; Stony Brook University in Stony Brook, New York; the University of Texas, El Paso; Johnson Space Center in Houston; and other institutions. This team is part of RIS4E, short for Remote, In Situ, and Synchrotron Studies for Science and Exploration, a five-year project led by Timothy Glotch of Stony Brook University. RIS4E is funded by NASA’s Solar System Exploration Research Virtual Institute, or SSERVI, which promotes collaboration linking science to human exploration.

Here, I’m pictured in the black leather cowboy hat I’ve worn on all field excursions for more than 15 years. NASA/GSFC

 

The Goddard Instrument Field Team, as a part of the RIS4E Project, explores Kilbourne Hole, a maar crater in the Potrillo volcanic field in New Mexico.NASA/GSFC

Helping me document the trip for NASA were Elizabeth Zubritsky, who worked with me on these blog entries, and two members of Goddard’s video team, David Ladd (producer) and Rob Andreoli (videographer).

Goddard Instrument Field Team (GIFT): Goddard Instrument Field Team

January 11th, 2018 by Jake Bleacher

The Goddard Instrument Field Team (GIFT) is a group of scientists and engineers at NASA’s Goddard Space Flight Center as well as their external collaborators. The team focuses on conducting field research campaigns in geologic settings that are analogous to locations on other planets and moons throughout the Solar System. We call these sites “planetary analogs,” and they help us learn how to interpret data from across the Solar System while focusing on understanding Earth better.

Just as we send spacecraft to explore other planets, we have a fleet of Earth-observing spacecraft that provide comparable data about our own world. Every space mission, whether Earth-focused or planetary-focused, provides data that helps us understand the local environment and the history or events that shaped the landscape. Often, though, it seems that for every answer we gain, we develop more new questions.

One way to answer these questions is to develop new instruments. At GIFT, we conduct field studies on Earth to help better inform the development of new instruments that could fly to other planets or could probe our home planet. Earth is but one of a series of planets that formed together in our Solar System, and there are many lessons to be learned about our celestial neighbors by studying our world. We also can learn more about our environment here at home by looking to other planets. GIFT carries out field deployments to a variety of locations to study the local geology and environment and looks at how those rocks might reveal knowledge about past environments. We use the lessons learned during those deployments to help develop new instruments and to improve instruments that will someday explore other parts of the Solar System to try and answer similar questions.

ICESat-2 Antarctic Traverse: On The Road Again

January 2nd, 2018 by Tom Neumann

By the time this hits the press, we will be well on our way. After building the sleds, tuning up the PistenBullys, and going for a couple of test drives around the station, we are about as ready as we are ever going to be. Onward!

Our route travels north along the South Pole Operational Traverse route for about 100km, then turns left and heads out to 87.979 degrees south. 750 kilometers of the great flat white!

While on the road, we will be staying the tents that Kelly described in her last post. Really, tents? Isn’t it cold down there? We expect the daytime temperatures to be in the -20F to -30F (-29C to -34C) range with relatively light winds and sunny skies. These tents warm up nicely in the sun, and will warm up to a good 30 degrees warmer than the outdoor air temperature. That makes the interior a balmy 10F (-12C), which is really not too bad.

Our kitchen tent is the largest tent and will accommodate all four of us. Along the back wall, we have fashioned a counter out of a box and an aluminum kitchen table. The cooking supplies, including a two-burner stove that uses white gas, are stored either in the box, or in the two purple kitchen boxes.  Generally, only one or two of us are in here at a time when cooking, as a little elbow room goes a long way.

Who wouldn’t want to cook in here – look at that counter space!

We each have our own mountain tent for sleeping. It’s always nice to have some personal space, and the multiple air mattresses, foam pads, and super warm sleeping bags make for a pretty comfortable evening. A couple of Christmas lights, some magazines, and it’s home sweet home for the next three weeks.

A super-warm down sleeping bag, plus Christmas lights, make for a comfortable tent.

Days are spent in our PistenBullys, collecting the GPS data of the ice sheet surface using survey-grade GPS systems that will be a critical piece of the ICESat-2 validation effort. We will spend about 300 kilometers around the 87.979 S line of latitude where the ICESat-2 data will be the densest. By comparing our measurements of the ice sheet elevation from the ground traverse, with the elevation measured by ICESat-2 on orbit, we will assess the quality of our on-orbit data and make any corrections necessary. We aim to cover our route in about three weeks and be back here at South Pole around mid-January. Happy New Year, and happy birthday Mom!

We’ll catch you in a couple of weeks!

-Tom and Kelly

Notes from the Field