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Definitely is. Gary Trubl would be a good person to reach out to if you want to see if anything has come from the workshop since.

Awesome! Thank you!

Hii, 

Is speed of Light direction ? I mean we have measured the speed of light in lap but can we measure in one way ??

I'm not entirely sure what you mean, Amaan. The speed of light has dimensions of distance per unit of time and tells us about how fast light travels through space in a vacuum. 

Yes, Derek makes very good videos!

In the event that active life or fossil evidence is found on Mars it is likely to fall into one of three categories; Panspermia, new genesis, or back contamination from Earth. Do we have contingencies for each of these categories or identification protocols?

C V Ivie

Hello,

I am an undergraduate student and am interested in astrobiology.  I am a junior.  I was BS biophysics, but I wanted to have the option to apply to dental school.  I changed my major to BS biology so I could graduate on time and meet the class requirements for dental school. 

I am just now learning more about the field of astrobiology and was wondering how I can get into a graduate school (Ph.D. program for astrobiology).  Is it okay if I have a BS biology degree?  I am involved heavily in the physics department at my school (doing research, cofounder and VP of the astronomy club, and member of CubeSat project).  

I am passionate about science, outer space, and learning about the universe.

Hi Taylor. It's absolutely fine to get into astrobiology with an undergraduate background in biology. You'll actually find that many of us have BS degrees in biology (I'm among the many astrobiologists who do!). There are lots of research areas and problems to work on from biology that are relevant to astrobiology. Also, while you are considering programs, please be aware that there are very few degrees for astrobiology. Rather, most of us earn our Masters and Doctoral degrees in other realms that relate to astrobiology, while some may also be able to attend schools that have astrobiology certificates and courses. So perhaps you might want to consider PhD program in biology where you can do research relevant to astrobiology. Although, you also can certainly switch gears to other fields if you'd like (I went from undergrad in chemistry and biology to astrophysics and then geology for my PhD). There is certainly not one right way to do it. There may be lots of options for you to follow to build your own path into astrobiology!

During the development of the sampling apparatus on the Perserverance Rover, there was encountered significant friction that prevented the sample tube from moving into the sample storage container.

Was a inert lubricant like graphite or silicone fluids considered as a means of reducing friction?

I am assuming that a major concern to avoid sample contamination, and many lubricants would not work for this purpose.

Hi Nelson — good question. Many options were considered, but the solution to the issue you’re describing was to change the cleaning protocol, not to add lubricants. We still had to meet the same cleanliness requirements, but we had to substitute different solvent rinsing methods for some of the final high temperature bake out of the tubes that was causing problems. The final approach still involved but solvents and baking, but this had to be optimized to enable both cleanliness and mechanical function. Cheers, Ken Williford

I have a Life on Mars question.  My understanding is that life on EARTH started around 3.8 billion years ago, and for roughly the next 2 billion years all of the oxygen which that life produced was fixed by the planet in oxidizing things like iron and copper.  It wasn’t until after that that atmospheric oxygen started to accumulate.  If this is true on earth, then wouldn’t it be reasonable to assume a similar process happened on Mars.  I read about scientists detecting methane on mars and suggesting it could be evidence of life, but shouldn’t the simple fact that the entire planet is oxidized be evidence of life?  If not, then where did all of the free oxygen come from to rust the planet?

Hi Andy! This is a great question and was actually one that I was just asked after a talk just this week :)

 

You're right about the fact that early on the Earth had almost no molecular oxygen in the atmosphere, and even once life started producing abundant oxygen it took some time before that oxygen accumulated in our atmosphere as it was first titrated out by reduced species with which it was reacting (this is part of the explanation for things like Banded Iron Formations). The timing at which the molecular oxygen began to rise in the atmosphere places the Great Oxidation Event as beginning somewhere in the 2.7 to 2.4 billions of years ago range, and was very much driven by biological process here on Earth. But we might not need such a largescale life-driven process to explain the oxygen that has rusted out Mars.

 

However, before offering any of the current hypotheses, it’s important to mention that we don’t know for sure yet how/why Mars became a rusted planet. But we do know that it is, and we also know that there doesn’t appear to be any signs as of yet of an ancient biosphere on Mars as developed as what Earth had during the timing of the GOE (these are good caveats to start with, since they suggest that there is more likely an abiotic reason!).

 

Firstly, our current knowledge of Mars is that it has a highly oxidized surface (and a highly oxidizing surface – check out the perchlorate salt issue for instance), and our models tell us that it has a highly reducing interior. And, unlike Earth, Mars doesn’t have active tectonic plate movement, especially not the type that drives for surface crustal material to be recycled into the mantle. So Mars doesn’t have a good means of recycling oxidized surface material into its crust. This is a good place to start in your thinking of the oxidized surface today.

 

For the rusting of Mars, one proposal is that the larger size and greater heating following differentiation from radioactive sources on Earth allowed for more primordial iron oxides to be practically smelted into iron metal that sank to the core of the Earth (https://www.nature.com/articles/nature02473). I personally don’t find this hypothesis very compelling, but having a greater surface inventory of iron oxides or other sources of iron could be an important part of the rusting of Mars.

 

Another hypothesis is that the infall of meteorites on the surface of Mars provided abundant raw iron metal for reacting with the Martian atmosphere, thus partaking in the titrating of water and oxygen out of the atmosphere for the weathering of the meteoritic metal (https://skyandtelescope.org/astronomy-news/rusting-mars-without-water/). This is an intriguing idea, and even though it might sound weird, we can model that a rather huge mass of meteorite material should have accumulated on the Martian surface over time.

 

My favorite of the better known hypotheses, though, is that the rusting of Mars went hand-in-hand with the loss of its water and the loss of its atmosphere. If Mars truly did have a very wet early history (which appears rather likely given our current research), then another potential source of oxides for the rusting of the Martian rocks was the slow and gradual splitting of water molecules, with escape to space causing loss of more hydrogen than oxygen and driving remnant oxygen in hydroxyl groups to react with the Martian surface rock, and thus causing the rusting. So, while some of the surface water may indeed be now trapped in permafrost in the subsurface or may have been lost to space over the eons, we might also be able to explain the loss of that water in the formation of the rusted surface of Mars.

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