Sunday, February 27, 2011

Saturday, February 26, 2011

Saturday February 26: The scientific story emerges, and a camel traffic jam

Saturday was a long day driving around the eastern portion of the Empty Quarter looking for good sabkhas.  We didn’t find much there, but now we know.  We took one car, with just Chris, Jon, myself and Arab Youth Venture Foundation staff member Annie Ortiz in it. 

Half an hour away from our hotel, we realized we had taken with us the key to another car which our colleagues needed.  So, we turned around to return the key.  During the hour that followed, driving over familiar roads, we discussed the scientific story that is emerging here.

Part of our purpose in making this trip was to look for hypoliths, which are stones colonized on their undersides by cyanobacteria.  It turns out that the Emirates aren’t good hypolith territory.  There is too much sand, and not enough of the right kind of stones.  We haven’t seen any, except a few very small ones near Jebel Hafeet.

But the salt-loving bacteria that live in the sabkhas here are excellent and interesting.  We humans can drink water that is only about 1/10th as salty as seawater, but seawater itself still feels “fresh” to some of these bacteria.  They can live in water that is a lot saltier than seawater. 

The sabkhas have groundwater a few feet underneath them that is probably fairly fresh.  It appears that the groundwater wicks upwards and evaporates at the ground surface, leaving behind layers of salt crust and brine.  In the top layers, cyanobacteria and halophilic bacteria thrive, protected from ultraviolet light and from drying out by the top centimeter of salt crust.  The translucent salt crust acts like a greenhouse window. 

The pink halophilic bacteria grow in the uppermost layer, with the green algae and cyanobacteria just below them.  Lower down there is a dark layer of bacteria.

Mars probably has salt flats like this.  Nothing can live on the surface of Mars because of the harsh ultraviolet light.  But, a centimeter of salt crust is all it takes to block the ultraviolet light, while allowing plenty of visible light to be transmitted.  So, this kind of environment is a good place to look for life on Mars.

None of this makes good photographs, so enjoy the photos I am putting here of us (with Annie at the wheel, as always) stuck in a camel herd.

Saturday February 26: Fun with the Sun

Today was long and busy, and I've run out of time to describe or post photos of what we did and what we learned.  Tomorrow I will catch up. 

Meanwhile, enjoy these sunset pictures.

Friday, February 25, 2011

Friday February 25: Camels

Our hotel is next to the Madinat Zayed Camel Racetrack and Training Grounds.  All day long trainers are coming and going, leading strings of camels to and from the track.  They run around the track accompanied by a pace car.   This is the most important racetrack in the Emirates.

We have seen thousands of camels in the rural areas around Liwa, but these are more beautiful because of the tack they wear.  

I could watch them all day.

Friday February 25: We go on TV

Today was press day.  We went back to the big sabhka near Liwa and met a crew from Abu Dhabi Media Incorporated, the national TV station.  We showed them our research and they interviewed Chris, Jon, myself and Hussain. 

I told them that NASA placed a priority on including students in research, and that in addition to helping prepare the artificial hypolith experiment, my students were following our research on this blog.  I also talked about our interactions with yesterday’s students from Abu Dhabi, and how we expected more students to visit us on Sunday. 

We were on the air at 8 and again at 11 tonight, and we were also featured today in a page 3 article in the Gulf News.

Jon cut a big plug out of the salt crust that shows the different layers of bacterial cells; brown, green and pink.  It looked like a big sandwich.  We left Liwa and drove out onto the gravel plains, looking for hypoliths but we did not find any.  There was too much sand, and none of the right kinds of rocks.  For astrobiologists, the sabhkas are the stars of the show here.

I found this skull of a goat, I think.

Thursday, February 24, 2011

Thursday, February 24: Dhafeer Fort

We stopped at Dhafeer Fort on the way home.  There are a lot of little forts like this one in the area of the Liwa Oasis.  Most of the old buildings here are forts. 

People around here mostly lived in tents in the old days, or small homes made out of palm thatch.  Those homes have not survived.

Thursday, February 24: A school field trip to the Empty Quarter

This morning we went to the big sabkha (salt flat) that we found last night along the road to Tel Moreeb.  We were joined by about 30 students and teachers from Cambridge High School in Abu Dhabi, an international school.  The students were from all over:  Germany, New Zealand, Pakistan, the Emirates, etc.  They were very engaged and they helped us collect some methane samples and make some measurements at this very interesting site. 

There was standing water in puddles, colored by pink and orange halophilic bacteria.  More bacteria, mostly green and pink, live in layers just under the salt crusts.  They are using the salt crust like a greenhouse window.  The salt lets some light through, but not too much.  It also protects against desiccation, and limits competition from other organisms.

After collecting our samples and saying goodbye to Cambridge High School, we continued south on this dead-end road into the Rub Al Khali, also known as the Empty Quarter.  This is the world’s largest area of continuous sand dunes, stretching about 600 miles into Saudi Arabia.  Jon Rask and I climbed a dune, and the heat was so intense it was hard to breathe.  It was at least 30 degrees F hotter on the dune than it had been on the sabkha, and it was warm enough on the sabkha.

Wednesday, February 23, 2011

Wednesday February 23: Internet Access

I hope you appreciate the effort and resourcefulness that go into making these posts from the field.  The Emirates are high-tech, and internet access is everywhere.  But, when you’re traveling with no fixed address it takes time to discover where the wireless spots are best.  This place was so good we called it “the office.”

Wednesday February 23: Field Work

Today we drove westward along the coast, past Abu Dhabi until we got to Tarif.  We stopped at a coastal site and waded out a little into the Arabian Gulf to sample methane gas and sediment at the edge of the sea.  We were only able to collect a little bit of methane.  Then we backtracked to sample from a puddle on an inland salt flat. 

After an excellent Indian lunch at a truck stop, we continued on to the elegant Tilal Liwa Hotel, which is out in the middle of the dunes, with nothing around it.  The Madinat Zayed Camel Racetrack and Training Grounds, a few miles away, is the closest thing.

After checking in at the hotel, we continued south to the Liwa Oasis and went into the dunes to look for salt flats in between them.  On the road to Tel Moreeb we found a good one.  Tomorrow we will bring visiting students from the local schools there.

Wednesday February 23: The Al-Jahili Fort

On Monday I had an hour to kill, so I went to see the Al-Jahili Fort, built in the 1890’s.  The Emirates have very few old buildings, but, as you can see, the few that are here are impressive.

The fort is surrounded by the modern city of Al-Ain, and is only a block from the downtown.  But, by careful positioning of my camera I have tried to show it as it might have looked in 1900, on the edge of the oasis with little else around. 

Tuesday, February 22, 2011

Tuesday February 22: A Field Trip, and Project Success!

Matt Reyes arrived last night from San Francisco.  He is NASA’s education/ public outreach coordinator for the expedition.

We went out in the field with Professor Asma Al Farraj Al Ketbi and some of her students from United Arab Emirates University.  We were looking at hypolithic cyanobacteria on the gravel plains near the border with Oman.  The students were very gracious, and very engaged.  It was fun spending time with them. 

On a gravel plain near the Jebel Hafeet we set up another installment of Drake High’s Artificial Hypoliths Project.  Sixty glass, marble and travertine squares were left on the desert floor for a few years with nobody for company but camels.  In time, some one will recover them to see if bacterial cells have colonized the undersides. 

Monday, February 21, 2011

Monday February 21: The Perfect Polygons site

We drove East of Al-Ain looking for a good salt flat.  This wasn’t easy even though we had several maps, a GPS unit and a sturdy SUV.  Recent construction and development made our maps inaccurate.  Miles of formidable looking camel fences separated the roads from the valley floors.  But, before noon we found the perfect site.

In the middle of a big valley there were salty pools of standing water, surrounded by polygons of sun-baked mud.  No camels had disturbed the soil crust.  In places the pools were green with cyanobacteria. 

Jon collected three samples of methane gas from the mud, and one sample of bacterial mat.  The methane will be analyzed back at the NASA Ames Research Center to find out whether or not these bacteria prefer to use carbon-12 over carbon-13.  There is methane on Mars, too, and nobody knows where it comes from.  Maybe bacteria like these are making it. 

Sunday February 20: Dubai Creek

Our leader Dr. Chris McKay of the NASA Ames Research Center, and Lucinda Land of the Mars Society flew in late last night and we joined them today.

We weren’t driving to Al-Ain until noon, so Jon Rask and I walked across town to Dubai Creek to see the boats.  It was a breezy, busy, place.  We walked by the beautiful Grand Mosque.

Saturday, February 19, 2011

Saturday, February 19: Arrival in Dubai

The time difference between Dubai and California is 12 hours, so it was not necessary for me to reset my watch as I stepped off the plane! 

The quickest route from San Francisco to Dubai takes you over the Arctic Ocean.  It is called a great circle route.  Don’t try to understand this while looking at a map of the world, but it will make sense if you look at a globe.  Because we flew across the arctic, we crossed all of Russia from the White Sea to the Caucasus.  Russia is covered with snow from north to south.  We saw a great view of Moscow from the window of the plane.  Then we flew the entire length of Iran, from north to south.  Emirates Airline takes really good care of you.

In Dubai I met Jon Rask who works for NASA and Lisa LaBonte and Hussain Al-Ansari with the Arab Youth Venture Foundation.  We went to admire the Burj Khalifa, the world’s tallest building at 828 meters.  “Burj” means “Tower” in Arabic.  This stunning building is a challenge to photograph, especially at night, because it is so tall and so dark.  I have done my best.

Saturday, February 5, 2011

February 5, 2011: In two weeks I take off for Dubai!

I have been invited to participate in NASA's Spaceward Bound program to the United Arab Emirates.  We will study cyanobacteria in the Arabian Desert, in order to better understand how life survives in harsh environments.  Some day what we learn may help us prospect for life on Mars - that is why NASA cares so much about cyanobacteria.

With me in the desert will be a international team of scientists, including NASA's Chris McKay and Jon Rask. Although the United Arab Emirates are famous for the rich and futuristic cities of Dubai and Abu Dhabi, I won't be spending much time in them.  We'll be inland instead, mostly in the university town of Al-Ain, and in the Liwa Oasis.  The map below shows where Al-Ain is.  The green pencil points to it.

I will post photos and journal entries to this site from the field each day that I have internet access.