nasa mars scientists

We’re NASA Mars scientists. Ask us anything about today’s news announcement of liquid water on Mars.

Today, NASA confirmed evidence that liquid water flows on present-day Mars, citing data from the Mars Reconnaissance Orbiter. The mission’s project scientist and deputy project scientist answered questions live from the Jet Propulsion Laboratory in Pasadena, California, from 11 a.m. to noon PT (2-3 p.m. ET, 1800-1900 UTC).

Participants will initial their replies:

  • Rich Zurek, Chief Scientist, NASA Mars Program Office; Project Scientist, Mars Reconnaissance Orbiter
  • Leslie K. Tamppari, Deputy Project Scientist, MRO
  • Stephanie L. Smith, NASA-JPL social media team
  • Sasha E. Samonchina, NASA-JPL social media team


News release:

Proof pic:

What will the next generation of robots we send to Mars look like? Now that there’s this new evidence will that change what testing equipment gets a space onboard? What’s the food like at the cafeteria at NASA?

[Leslie K. Tamppari] We are planning to send the InSight lander to Mars in 2016, which will be lander designed to detect Mars-quakes. We also have a rover in development for the 2020s (same basic design as MSL/Curiosity) and NASA is considering the science that might fly on the next Mars orbiter to be launched sometime after the 2020 rover.

The instruments that are chosen to fly are selected because they can accomplish the science goals of the mission, so as the science goals change – with new discoveries – instruments will be proposed and selected accordingly.

The food at JPL is actually quite good! Wood-fired pizza, burgers, sandwiches, good salad bar, etc.

I read that the rover can’t approach specific areas (including where the streaks are located) due to risk of infection by Earth microbes. What are some examples of microbes that could be living on the rover that you are concerned with infecting the surface of mars?

[Rich Zurek] These features are on steep slopes, so our present rovers would not be able to climb up to them. Because liquid water appears to be present, these regions are considered special regions where we have to take extra precautions to prevent contamination by earth life. Our current rovers have not been sterilized to the degree needed to go to an area where liquid water may be present.

If the rovers haven’t been properly sterilized already, will this throw doubt upon any possible future discovery of Mars-based microbes living in or near the water? Wouldn’t detractors be able to claim that they are microbes that somehow survived from Earth?

[Rich Zurek] The rovers have been sterilized for their particular landing sites where there’s been no evidence of present day liquid water. To go to the RSL rovers will be required to be sterilized to a higher level. We also take samples of microbes that might be on the spacecraft before they’re launched, so we can compare with any future discoveries.

Could you explain why you can’t go near the water? Is it for fear of harming the rover? Or contaminating the water?

[Rich Zurek] It’s both. The dark streaks are on slopes that are too steep for our present rovers. Also, we want to be careful to not introduce Earth bugs into an environment that may have liquid water.

What quantity of water are we talking about? What volume?

[Leslie K. Tamppari] We think this is a very small amount of water — maybe just enough to wet the top layer of the surface of Mars. The streaks are ~4-5 meters wide and ~200-300 meters long.

How much liquid water are we talking about? Like.. tap water leaking when you don’t close the valve tight enough, or Niagara falls?

[Rich Zurek] Tap water leaking.

What’s the next step?

[Rich Zurek] The next step is to look for more locations where brine flows may occur. We have covered 3% of Mars at resolutions high enough to see these features.

When talking about exploration or colonization of Mars or whatever it’s so easy to forget that even if it’s a lot smaller than Earth, it’s still a planet that we’re talking about.

[Rich Zurek] The surface area of Mars is nearly the same as the land area of the Earth.

How long into the future do you think it will be before we can realistically think about sending humans to Mars?

[Rich Zurek] Presently, NASA is looking into the possibility of sending humans to the vicinity of Mars in the early 2030s. In this scenario, the earliest humans to the surface would be in the late 2030s.

This may be a bit far-future looking, but does the fact that we know liquid flowing water exists mean anything for terraforming Mars in the future?

[Rich Zurek] Think of this as a “seep” not a flow. We have not seen flowing water on the surface. We see something that darkens the soil, which may be just a wetting action but still involves (briny) liquid.

It was shown back in 2011 that salt water flows may be a seasonal occurrence. What was the final proof for the team that this was happening, and what was your initial reaction to the data?

[Leslie K. Tamppari] With MRO, we were able to observe a few of these sites at various points within the Mars year, and again the next year. Over time, we saw that the streaks darkened and lengthened during the warm season and faded during the cold season. A benefit of having MRO lasting so long is that we’re able to see changes and patterns over time.

My reaction? This is all very exciting! The closer we look at Mars, the more interesting it gets.

If the Mars rover were to travel to the site of the briny water, what would be the scientific procedure for determining if that water supports life?

[Rich Zurek] The Curiosity rover does not have life detection instruments. It would look for confirmation that liquid water was present and how long during the day it was liquid.

Could there be Martian life in the water since it’s only there at certain times of the year? What might happen to the life when the water disappears? It was mentioned that there’s life on Mars in the form of microbes on the machinery. Is it possible that these microbes sent by us could harm Martian life?

[Leslie K. Tamppari] It’s possible. We know of forms of life that hibernate during dry seasons on Earth. The water that we’re seeing within the RSL (the seasonal dark streaks that we’re seeing on slopes on Mars) is salty. Salty water could be harmful to life.

We don’t know what Earth life could do to any potential life on other worlds. That’s why we try to clean our spacecraft very carefully.

Is there any evidence of evaporation happening on mars? And do you know where this water came from?

[Rich Zurek] New impact craters on Mars sometimes have bright ice exposed in the bottom of the crater. This goes away over a few months. The ice, when exposed, is going from solid to vapor. Evaporation of a briny flow will also occur, so the water needs to be resupplied. We don’t know how.

What would be the procedure, if life is found on Mars? Would the public be made aware? Who gets told first?

[Stephanie L. Smith] Information flows to the public very quickly. If one of our missions here at JPL detected life, we’d notify NASA headquarters immediately, who would then follow procedures to notify the US government and the public.

How close is the rover to the water? Will you be able to get close enough to get pictures without contamination?

[Rich Zurek] There are no confirmed brine flows (RSL) near Curiosity nor Opportunity. There are in Gale Crater some interesting slope streaks but they are several km away from the Curiosity’s present path.

What do you say to those who would argue we already had proof with the ice caps? Obviously, they’re full of water. Don’t they melt periodically?

[Rich Zurek] The ice caps freeze and sublime (solid to vapor.) The RSL water stays liquid because it has salts in it. Yes, we know there’s water on Mars. We’re looking for where it stays liquid for an extended period of time.

Where does the water come from? I understand that water vapor is very low in the martian atmosphere, yet surely there must be a sizable partial pressure of water vapor in order to hydrate the salts.

[Leslie K. Tamppari] We don’t know where the water in these hydrated salts come from. That is the next mystery to solve! They leading hypotheses are that (1) the salts are sucking up the water from the atmosphere, but you are correct, there isn’t much water in the atmosphere, and (2) that the water is coming from the subsurface. There is certainly more to learn!

What does this mean in regards to possible life?

[Rich Zurek] We think liquid water is essential for life (at least as we know it.) That does not mean that life is there; but, it’s a good place to look.

About how much longer do you think it will take to get visuals of the rest of Mars at a high enough resolution to see these types of things?

[Leslie K. Tamppari] MRO has been taking data at Mars since March 2006, nearly 10 years. The HIRISE instrument (high-resolution imager) has currently taken images of only about 2.4% of the surface.

Given the seasonal nature of today’s discovery, does this suggest that their is a hydrologic cycle on Mars?

[Rich Zurek] There is a hydrologic cycle on Mars, but typically it involves vapor going to ice (frost) or ice going to vapor. There is no rain in Mars today, but there may have been very early in its history.

In the articles I’ve read so far, the water is referred to as “briny” and that it’s more fluid than it is water. What does that mean? Would this be something theoretically possible to drink or grow things with? Or would this be the kind of thing that would need purification before it could be used?

[Rich Zurek] The salts in the water appear to be perchlorates, so I wouldn’t want to drink the water. To be a future resource for humans, you would want to remove the salts.

Do any of the space scientists at NASA write poetry/do art? If their art is inspired by their scientific work, can you please share it with us?

[Stephanie L. Smith] Absolutely. It takes all kinds of creative minds to do science and engineering that no one has ever done before. Among our mission teams, you’ll find actors, musicians, sculptors, painters — the list goes on. For visual artists, two individuals who spring to mind are Bill Hartmann ( and Dan Goods (

Scale of 1-10, how excited does this make you guys? Is this a huge deal for the scientific community?

[Leslie K. Tamppari] This is super exciting! It is an important discovery because it is evidence that supports our hypothesis that the RSL (seasonal dark streaks that appear to flow in the warm season) are flowing briny (salty) water.

What was the hardest technical challenge you faced on this project? What was the hardest nontechnical (political, cultural, legal, emotional &c) challenge?

[Rich Zurek] The features that darken and fade as temperatures get warmer and then colder are long but narrow. The difficulty was to get enough resolution from our orbiter instruments to first detect, and then characterize what these features are. Mars Reconnaissance Orbiter (MRO) can do that with its HiRISE camera and CRISM Mineral Mapper.

How long has water been on surface of Mars?

[Leslie K. Tamppari] Water in some form has probably been on Mars since at least 3.9 Bya.

This seems to indicate that mars is closer to the end of its life cycle than a younger planet like Earth (as in, a long while ago mars had flowing water, oceans, and likely life.. now it’s mostly arrid) What are your thoughts on that? I can hardly fathom what kind of life may have once been on Mars – but it’s kind of depressing to think that it is something that was once but unless terraforming becomes a thing – Mars will remain a grave stone of a world where life once may have thrived.

[Rich Zurek] Mars had liquid water on its surface billions of years ago. Where that water went is the subject of our current investigations. Was it lost to space? Or is it frozen in the crust today? Mars seems to have ice ages when water at the poles is sublimated and redistributed to the rest of the planet. Ice in the crust today may have been formed during one of those ice age cycles.

What procedures does NASA have in place to prevent potential contamination of these active water sources on Mars?

[Leslie K. Tamppari] We have a policy for Planetary Protection. This policy means that we clean our spacecraft of earth microbes to varying degrees depending on where the spacecraft is being sent. It the intended location is thought to have a high possibility of harboring microbes, then we go to the maximum extent to clean the spacecraft.

Will 2016 mars mission aim to explore more on this?

[Leslie K. Tamppari] No. The 2016 NASA Mars mission, InSight, will put a seismometer on Mars to measure Mars-quakes.

Is this water we’re taking about, or could it be another liquid?

[Leslie K. Tamppari] The signature that was seen by the MRO CRISM experiment was hydrated perchlorates. This means that water (H2O) was involved.

Why should the average joe care about this? What does this mean for science and space exploration?

[Rich Zurek] Liquid water, even if very salty, is still a good place to look for life forms. We don’t know how robust martian life (if it exists) could be. Also, water in any form is a resource that future missions could exploit.

How long before you guys can map a significant area (~20%) of Mars with Hi-Res images?

[Leslie K. Tamppari] MRO has been in orbit for 10 years and has mapped ~2.4 percent of Mars in high-res. We have six-meter-per-pixel imagery of more than 90 percent of the surface.

With the discovery of water on Mars does that mean there could be rainbows on Mars?

[Rich Zurek] Not quite rainbows, because there is no rain, but we have seen icebows with the Pathfinder mission.

Why is this a surprise considering there’s evidence of ice and glaciers? From what I saw when I Googled it, Mars can get warm enough to melt ice, so what’s to say this isn’t from the glaciers melting and then refreezing?

[Leslie K. Tamppari] The RSL are a surprise because they appear to flow seasonally and the best hypothesis is due to liquid, briny water. Mars can get barely above freezing for short periods above time. The RSL are not though to be due to glaciers because where they are seen (equatorial and mid-latitude regions) we do not see glaciers.

If the atmospheric pressure on surface is the same as Earth’s, but the air composition is the same as well as the soil/terrain, how likely would we be seeing streams or ponds of liquid water there?

[Rich Zurek] If the atmospheric pressure on Mars was the same as on Earth, then conditions are warm enough that water could be liquid on many places. The atmospheric pressure may have been greater in the past when the Mars channels were formed.

The gravity on mars is about 3.711m/s. Is this much gravity enough to hold a large amount of water on its surface? What will happen if we pour 200 gallons of water on the surface? Will it evaporate?

[Rich Zurek] If you pour pure water on the surface (depending on the time of day) it will either freeze or boil away into the atmosphere. The salts that were talked about in the press release today would keep the water liquid at much lower temperatures. Remember that the temperatures on Mars change by more than 100 degrees Celsius every day.

As someone who knows little to nothing about anything related to space exploration. What took us so long to discover this?

[Leslie K. Tamppari] Discovering the RSL (seasonal dark slope streaks) took having an orbiter (MRO) observing over multiple Mars years. Then, we had to form the hypothesis, and then go test it, by taking observations with the CRISM spectrometer. The features are small (4-5 m in width, and 200-300 m length) and only when there are many RSL together can it fill enough of the CRISM pixel to get the signal.

Do you know how much water there actually is on mars? Is it enough to support a city, for example?

[Rich Zurek] At the North pole there is a polar tap made of water ice, which is a mile thick and several hundred km across. Todays story was focused on liquid (briny) water closer to the equator.

Does Curiosity have any sensors capable of testing for bacteria? Since there is salty water (with an abundance of Calcium Perchlorate along with other salts) could we also assume that there is a greater possibility that their is life being it in the form of bacteria that can consume the Calcium Perchlorate?

[Leslie K. Tamppari] Curiosity does not have any sensors capable of testing for bacteria. They have the SAM instrument that can detect compounds, including organics.

Are there any ideas on the origin of this water?

[Leslie K. Tamppari] We don’t know. It could be absorbed from the atmosphere; it could be coming up from the subsurface. More investigation would be required.

Would you recommend high school students study to become scientists, or is there another field that you feel may be more up and coming in the future?

[Leslie K. Tamppari] I would recommend that high school students follow their interests. Try to get into a field that you enjoy! If one is curious and wants to discover new things, then becoming a scientist is a great option!

Would farming ever be possible in the areas where water has been found?

[Rich Zurek] Salty water is not good for crops; therefore, you would have to purify the water.