Updated:
Wednesday, December 3, 2003 8:59 AM
Are there any correlations between the cellular reproductive cycles of the organisms you've found and their diurnal cycles...
...I have wondered if there were any connections between cellular reproductive cycles and ultraviolet radiation, because during cellular reproduction the genetic material is very vulnerable to radiation and given the nature of the location you are studying, it would not be odd to find that they have developed certain instinctual behaviors to compensate.
We have not yet cultured organisms or observed their reproductive cycles. You are correct that the genetic material of cells is especially vulnerable to damage during reproduction and that this may result in somewhat different reproductive cycles. In addition, some organisms have developed certain pigments which protect them from UV radiation and some only exist in environments sheltered from solar radiation. In this way, compensations separate from the timing or biochemistry of reproduction result in the same effect: the genetic material is protected.
Why do you have to go to the highest lake?
The highest lake has properties that are unlike any that are found at lower altitudes. It has conditions that are very similar to those found on an early Mars, and so we want to know why types of organisms can survive in such a harsh environment. This environment has high ultraviolet radiation, low oxygen, and cold temperatures.
How hard is it to breathe in a high altitude?
Breathing at this altitude can be very difficult. The amount of oxygen found here is very low. Consider it this way: Breathing at 20,000 feet is kind of like completely removing 1-lung at sea level and trying to breathe.
My students are wondering how the formation of these lakes compare with the formation of Crater Lake in Oregon.
Dawn Burhans - 8th Grade
dburhans@pacheco.k12.ca.us
Pacheco Elementary
Answer: Both lakes resulted from precipitation filling in a volcanic crater. So, their formation mechanisms are the same. What makes volcanic lakes different from ordinary lakes is the potential for fluid input from the volcano. Ground water percolates down, gets hot, and rises by thermal buoyancy. If we boil water to remove bacteria, how does the lake that is warm have life in it?
Answer: Because the lake is not at boiling temperature. Although "warm" compared to the environment, it is only 6 degrees C. Also, there are bacteria, such as those in Yellowstone, that grow well at almost boiling.
If there is a hot spring below the surface of the water, is it supplying oxygen into the lake, and therefore the air around the lake?
Answer: Probably not. The algae in the lake, however, make oxygen like any plants.
Are there any animals living there?
Answer: In the lower lakes, we have flamingos, ducks, small crustaceans, insects, and so on. In the summit lake, we are looking for them and are hoping to find them. So far, all we know about in the summit lake are microorganisms.
How were the lakes formed?
Answer: The lower lakes were formed 15,000 years ago because the climate was different - there was more precipitation. They were much deeper then. The summit lake was probably formed due to precipitation. We are trying to show one way or another if there is an hydrothermal system contributing to it.
What is the boiling and freezing point of water at your altitude and what other characteristic properties of elements are different because of the high altitude and lack of atmosphere?
Answer: The boiling point is lower at higher altitudes because of the reduced total pressure. We do not have the exact numbers here at this time. At lower pressures, you can dissolve less gas in fluid - so if you open a can of soda, a lot more gas comes out. This may be important for biology at the summit lake, which can hold less oxygen, for example. Other than boiling, freezing and gas retention, not a whole lot changes.
Answered by: Andrew N. Hock
How do the extreme conditions at the summit lake compare with the conditions scientist estimate existed on Earth when the earliest life forms first appeared (on Earth) millions of years ago?
Asked by:
Dennis Mitchell
guyscience@aol.com
8th Grade
Answer: You have the same atmospheric pressure, the same range of temperature, a similar high-UV radiation environment, and the lakes on Mars were probably frozen part of the year. Sedimentation likely occurred the same way in both places, and both would be hydrothermal environments. It is an almost perfect environment. Which planet or natural satellite (moon) in our Solar System comes closest to resembling the conditions found at the summit lake?
Answer: Mars - 3.5 billion years ago, and this is why we are here.
Are there areas on Mars that have similar conditions found at the summit lake? If so, which areas of Mars have similar conditions and at what time of years are these conditions found on Mars?
Answer: 3.5 billion years ago, lakes on Mars were very similar to the lake on Licancabur today. Today, at the equator of Mars, the same range of temperatures are found (-40 to +10C) during summer on Mars.
What kind of chemicals are in the water?
The chemical content of the summit lake is very similar to normal freshwater reservoirs and lakes...Licancabur lake is just a little bit more salty, though. It appears that the levels of some chemicals associated with volcanic gases are higher than in a regular lake, but we need to do more work on this during our current expedition. Some of the chemicals associated with volcanism are chloride and sulfate. We also found elevated levels of some metals, like iron, magnesium, and aluminum.
What would happen if you didn`t let your body adjust to the different heights?
How come you made all of those stops instead of going straight to the mountain?
These two questions have to do with acclimatizing, or preparing your body, for altitude. If you don`t let your body adjust, you may become very sick. Basically, as you go up in elevation, there is less and less oxygen available, which your lungs need to provide your body and mind with energy. Your body is able to cope with many changes, but if you go up in altitude too quickly, the lack of oxygen can be troublesome. Some people get headaches or upset stomachs...many people feel tired or have trouble sleeping. More serious illnesses can occur, as well; some high altitude mountaineers have even died from altitude-related illnesses in remote locations. This is why we take our ascent so seriously and stop to let our bodies adapt—when you go to high altitude slowly, your body is allowed time to rest and build more red blood cells to carry the little bit of oxygen it`s given. One other reason we make stops is to pick up equipment and supplies as needed: the volcano is in a very remote location, and we have to bring everything we need with us.
Do you like climbing the mountain?
Yes, very much. We are rewarded at every look behind us by beautiful views and with every step by strong friendship with our teammates. Although it is strenuous, it doesn`t require being tied in like technical rock/ice climbing or some mountaineering.
What do you think the chances of life being on Mars is?
This is a very difficult question. When my friends ask me this question, I usually respond this way: I believe that the question is worth asking, and worth working on an answer to. The experiments that the Viking mission performed in the 1970s were inconclusive, but suggested that life on the surface was unlikely. However, as our understanding of life on Earth has grown, we have learned that life is very adaptable, and can survive even under very harsh conditions. As far as we know, life (in particular, simple microbial life) exists on Earth in most places—even the most extreme—where water and a source of energy/nutrients is available. On Mars, these ingredients may be available and life may be possible, but we just don`t know the answer yet. So, we continue working and searching; one way we do this is through projects like this, where we investigate places on Earth that are similar in some ways to Mars.
How big is the mountain?
The mountain, Licancabur Volcano, has an elevation of about 6014 m and its summit is about 1500 m above the surrounding terrain. It is an impressive feature on the horizon—it can be seen from many miles away.
How hot and cold does it get there?
At the lagunas, the summertime air temperature ranges from about +12 to –12 C, and the average is about 0 C, or freezing. It gets much colder with increasing altitude: last year, we measured temperatures at night down to –30 C and daytime temperatures only a couple degrees above freezing. The annual average air temperature at the summit is probably about –13 C. Cold.
How long can you hold your breath?
We did some breath holding excercises at around 8000 feet elevation; there, we held our breath between one and two minutes. At sea level, Andy can hold his breath over three minutes. However, these are `static` experiments, where we only held our breath without performing any other activity. While diving and doing scientific experiments, we will stay under for less than one minute.
Who is the first person to climb the mountain?
The people native to this land, the Atamencanos, and the Incas were probably the first to climb this mountain. Archaeologists have found small Inca ruins at the summit of Licancabur, proving their presence there long before ours.
How deep do you guys think you will go into the lake?
Because of the altitude, we have to be careful about the depth and pressure. Although we could push the envelop depending on how we feel, we have set a limit at 3 meters. Beyond that, we will use instruments that will allow us to sample the bottom without having to go to the bottom. However, because we will be underwater, we will be able to select precisely the region of the lake we want to sample. This is extremely important because we are trying to understand life and habitats. In this specific case, random sampling would not be good enough. How are you going to breathe unerwater without any air tanks?
We will hold our breath. We have been training very hard in the past months at what we call free diving. Some members of the team have reached 3 minutes. Of course, that was at sea level but we also trained at altitude in north american lakes. Although the time underwater is a bit shorter, the team does pretty good. Now, the goal is not to hold our breathe as long as we can here. We want to explore safely therefore we will always keep a safety margin not to be out of breathe when we come out of the water. As you know, at 6,000 m, the atmosphere pressure is 48% of that of sea level. The air is VERY thin. We want to have some reserve. Moreover, we will have oxygen tanks near us in a boat, just on case we need a little support. Why are you free diving?
The Licancabur is a very high mountain and if diving tables are well-known in the ocean, there are no real tables for this altitude (6,000 m). Using mixtures of gas would be dangerous because of the partial pressure of gas. The waiting stages at various depths when you are coming out of the water are a lot shorter and it is much easier to make a mistake. At this altitude, such mistake could mean BIG trouble. We could use pure oxygen but this gas also has its own downside. Breathing on pure oxygen for quite some time and surfacing in an atmosphere that is only 48% of that of sea level could lead people to faint, which is not an ideal situation. How long can you hold your breathe
At sea level, the maximum for the team is 3 minutes with a solid average around 2 min 15 sec. At 2,400 m, the maximum is 2 minutes with an average around 1 min. 30 sec. We have been monitoring and recording our physiological data and times very seriously. We will do the same at the summit. Is it scary to jump into the highest lakes on Earth
No, it is not. It is very exciting. Fear is not the specific term I would use (Nathalie speaking). We have to be aware all the time of our very special environment, therefore extra cautious. It is more of an extreme concentration coupled with lots of expectation, especially because we know that these lakes potentially hold very important scientific clues for the evolution of life on Earth and possibly on other planets. How long has Nathalie been on the team?
Nathalie responds to this question: Well, I created the team since I am the principal investigator of this project. I wrote the science project which was selected by NASA and I selected my team members. Then, we also had new members joining us through collaboration with Bolivia, Chile, Hungary, Spain. TO make a long story short, I have been here since the very beginning. Why did you pick Licancabur?
The lake ontop of Licancabur is among the highest lakes on Earth, most of them being located in the Andes. The conditions of atmospheric pressure, temperature, high UV radiation, volcanic, tectonic, and hydrothermal environment are possibly the closest analogs to Mars 3.5 billion years ago when there were still lakes on the red planet. Since we want to understand the habitability potential of Mars in the past, it is important to go to place that are good analogs. Licancabur is definitely one of the best on Earth.
What are you planning to do differently to find new life?
Last year´s reconnaisance allowed us to investigate the physical and biological environment of the summit lake for the first time. In part, we learned that the extreme ultraviolet radiation levels (due to high altitude, low latitude) may be responsible for a high mutation rate observed among diatoms in the lake. Observations like this have helped us design new experiments to look for life in the lake. This year also, we will be taking samples from the UV plate experiment conducted by Edmond Grin, which has been installed for one year. Samples from this experiment may illustrate the effects of ultraviolet radiation on the biological community. Finally, we will be diving in the summit lake this year, which we could not do last year because we run out of time after bad weather delays. We have planned a lot more time this year to make it happen. The diving will allow us to look for life in new locations, and we will have new biology team members whose expertise will help us with this search. It is a normal evolution of the project which needed to be focusing first on understanding the environment and then, identifying and characterizing life. This is the two step process that we undertook last year and this year we are moving towards more biology. Do you have an estimate on how deep the lake is?
In 1984, an adventurous group of divers set out to establish the world record for high altitude SCUBA diving at the Licancabur summit lake. They succeeded, despite an ice cover nearly one meter thick, and measured the depth of the lake to be approximately 4 meters. However, the slope of the crater wall suggests that the lake may be ~10 meters deep. Depth is an important parameter in understanding life and physics of the lake; this year we will use a handheld sonar unit to measure the depth of the lake on site. What are you wearing to protect your skin from UV rays?
Our team members all wear hats, sunscreen and lip balm; in this environment, it is very important to protect your body from the harsh elements of the local climate. We also wear gloves and sunglasses to protect our hands and eyes from bright sun and cold, dry winds. What is the average temperature of the air and the lake?
The average air temperature at this altitude and latitude is about -13 Celcius but may go down to -30 C at night...what Nathalie calls ¨ouch¨ cold. The daily temperature at the refuge ranges from about -10 to +10 Celcius. Finally, Andy measured the lake surface temperature last year and found it was 5 C, but the lake top freezes during part of the year and in 1984, John Leach and others measured the lake bottom temperature nad found it was 6 C. [Conversions Table] Understanding this variation is part of our work here.
About how old is some of the stuff you will find?
Licancabur is a relatively young volcano--with no evidence of glacial erosion it may be younger than the last glaciation, which ended 10,000-15,000 years ago. This year, we will also investigate the relationship between Licancabur and the lagunas at its base. It appears that the ancient "superlake," which was the large body that has slowly evaporated to give rise to Lagunas Blanca and Verde, may be about 15,000 years in age. Understanding whether Licancabur existed before, after or during this superlake will help us pin down its age. In terms of local buildings,the Inca village between Licancabur volcano and Juriques volcano is about 500 years old, while the refuge we stay in is about 10 years old. Finally, in terms of the timescale of life at this site, one generation of diatoms lasts approximately three weeks, about the same amount of time of our stay at Licancabur.
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