You can't prove a negative. There's really no way to prove Mars didn't have or doesn't have life.Which definitely doesn't mean we shouldn't look or go.
Remember that even now, after decades of work, not everyone is convinced that there was life on the Archean Earth. Although there almost certainly was, IMHO.
Quote from: Dalhousie on 07/23/2016 11:45 pmRemember that even now, after decades of work, not everyone is convinced that there was life on the Archean Earth. Although there almost certainly was, IMHO.The explosive (not really, but you know what I mean) march of life across the early Earth really does imply lots of viable precursors/attempts/follies or even panspermia here and elsewhere. Even in the 'simple' early times, it looks like things were never simple or early! The implication of the surprisingly fast spread of life in the not terribly nice early Earth environment is that it also kicked off elsewhere whenever it could - but remember that 'life' need not be more than highly evolved and rather efficient slime with becoming a stromatolite as a career objective...
Quote from: Bob Shaw on 07/24/2016 12:22 amQuote from: Dalhousie on 07/23/2016 11:45 pmRemember that even now, after decades of work, not everyone is convinced that there was life on the Archean Earth. Although there almost certainly was, IMHO.The explosive (not really, but you know what I mean) march of life across the early Earth really does imply lots of viable precursors/attempts/follies or even panspermia here and elsewhere. Even in the 'simple' early times, it looks like things were never simple or early! The implication of the surprisingly fast spread of life in the not terribly nice early Earth environment is that it also kicked off elsewhere whenever it could - but remember that 'life' need not be more than highly evolved and rather efficient slime with becoming a stromatolite as a career objective...Nice way of putting it. But don't forget evidence of life is rare in rocks older than 3 Ga, uncommon in rocks 1.8-3 Ga, and it isn't until after about 1.8 Ga that it becomes geologically common. You can traverse kilometres of geological section in Archean rocks and not find any evidence of life.
Quote from: Dalhousie on 07/24/2016 07:42 amQuote from: Bob Shaw on 07/24/2016 12:22 amQuote from: Dalhousie on 07/23/2016 11:45 pmRemember that even now, after decades of work, not everyone is convinced that there was life on the Archean Earth. Although there almost certainly was, IMHO.The explosive (not really, but you know what I mean) march of life across the early Earth really does imply lots of viable precursors/attempts/follies or even panspermia here and elsewhere. Even in the 'simple' early times, it looks like things were never simple or early! The implication of the surprisingly fast spread of life in the not terribly nice early Earth environment is that it also kicked off elsewhere whenever it could - but remember that 'life' need not be more than highly evolved and rather efficient slime with becoming a stromatolite as a career objective...Nice way of putting it. But don't forget evidence of life is rare in rocks older than 3 Ga, uncommon in rocks 1.8-3 Ga, and it isn't until after about 1.8 Ga that it becomes geologically common. You can traverse kilometres of geological section in Archean rocks and not find any evidence of life. Is there abundant evidence for life in metamorphosed rock from the most recent billion years?
Curiosity is currently about 5 kilometres away from the potential RSLs; on its current projected path, it would never get any closer than about 2 kilometres, Vasavada says. The rover could not physically drive up and touch the streaks if it wanted to, because it cannot navigate the slopes of 25 degrees or greater on which they appear.But the rover’s sheer unexpected proximity to potential RSLs has NASA re-evaluating its planetary-protection protocols. Curiosity was only partly sterilized before going to Mars, and experts at JPL and NASA headquarters in Washington DC are calculating how long the remaining microbes could survive in Mars’s harsh atmosphere — as well as what weather conditions could transport them several kilometres away and possibly contaminate a water seep. “That hasn’t been well quantified for any mission,” says Vasavada.
Someone should run a public opinion poll for approach/don't approach, just to amp up the pressure. Hey even a NSF poll would be cool
One minute they are going to check them out, the next minute it's oh we must keep many kilometres away.
Quote from: Welsh Dragon on 07/05/2016 01:41 pmQuote from: gospacex on 07/01/2016 09:58 pmUS society is getting way too paranoid about "safety" and "protection" of just about anything.I take it you're not a biologist? I am, and I can guarantee you it is not possible to be too paranoid when it comes to contamination of biological samples.Yes it is, if it prevents you from doing the work.
Quote from: gospacex on 07/01/2016 09:58 pmUS society is getting way too paranoid about "safety" and "protection" of just about anything.I take it you're not a biologist? I am, and I can guarantee you it is not possible to be too paranoid when it comes to contamination of biological samples.
US society is getting way too paranoid about "safety" and "protection" of just about anything.
In the world of sciences, it is generally best to avoid gathering data that is flawed or of which the accuracy is uncertain (hence possibly contaminated biological samples).
Quote from: Dalhousie on 07/23/2016 06:02 amQuote from: Welsh Dragon on 07/05/2016 01:41 pmQuote from: gospacex on 07/01/2016 09:58 pmUS society is getting way too paranoid about "safety" and "protection" of just about anything.I take it you're not a biologist? I am, and I can guarantee you it is not possible to be too paranoid when it comes to contamination of biological samples.Yes it is, if it prevents you from doing the work.And what exactly would the purpose be of doing work that is potentially flawed to the point of being worse than doing nothing? In the world of sciences, it is generally best to avoid gathering data that is flawed or of which the accuracy is uncertain (hence possibly contaminated biological samples). Gathering such data can indeed often be better than nothing and allow for some hypotheses to be evaluated beyond reasonable doubt, but in some cases (life sciences in particular) it is more likely to lead one astray then to benefit them scientifically.
Quote from: vaporcobra on 09/09/2016 08:07 amIn the world of sciences, it is generally best to avoid gathering data that is flawed or of which the accuracy is uncertain (hence possibly contaminated biological samples). It's not ever as clear cut as that. Time and again flawed datasets with large uncertainties have been revisited, sometimes decades later, with new analysis methods, cross referencing and complementary newer data etc.
Quote from: vaporcobra on 09/09/2016 08:07 amQuote from: Dalhousie on 07/23/2016 06:02 amQuote from: Welsh Dragon on 07/05/2016 01:41 pmQuote from: gospacex on 07/01/2016 09:58 pmUS society is getting way too paranoid about "safety" and "protection" of just about anything.I take it you're not a biologist? I am, and I can guarantee you it is not possible to be too paranoid when it comes to contamination of biological samples.Yes it is, if it prevents you from doing the work.And what exactly would the purpose be of doing work that is potentially flawed to the point of being worse than doing nothing? In the world of sciences, it is generally best to avoid gathering data that is flawed or of which the accuracy is uncertain (hence possibly contaminated biological samples). Gathering such data can indeed often be better than nothing and allow for some hypotheses to be evaluated beyond reasonable doubt, but in some cases (life sciences in particular) it is more likely to lead one astray then to benefit them scientifically.What makes you think the data is so flawed as to be worse than doing nothing? Its hard to think of a scenario in this case where this would be the case?
Quote from: Dalhousie on 09/10/2016 05:48 amQuote from: vaporcobra on 09/09/2016 08:07 amQuote from: Dalhousie on 07/23/2016 06:02 amQuote from: Welsh Dragon on 07/05/2016 01:41 pmQuote from: gospacex on 07/01/2016 09:58 pmUS society is getting way too paranoid about "safety" and "protection" of just about anything.I take it you're not a biologist? I am, and I can guarantee you it is not possible to be too paranoid when it comes to contamination of biological samples.Yes it is, if it prevents you from doing the work.And what exactly would the purpose be of doing work that is potentially flawed to the point of being worse than doing nothing? In the world of sciences, it is generally best to avoid gathering data that is flawed or of which the accuracy is uncertain (hence possibly contaminated biological samples). Gathering such data can indeed often be better than nothing and allow for some hypotheses to be evaluated beyond reasonable doubt, but in some cases (life sciences in particular) it is more likely to lead one astray then to benefit them scientifically.What makes you think the data is so flawed as to be worse than doing nothing? Its hard to think of a scenario in this case where this would be the case?It's very easy to do that; where contaminations aren't recognised as such and give you false positives.
How far can the Chemcam be and still get a return from a wet surface?
Liquid water is one of the definitions for a special region. For special regions post Viking sterility is necessary. 0,03 spores per squaremeter. This is not what Curiosity was built for. The assembly in the large cleanroom with the garment used and without a final DHMR cycle this levels can not be reached. The text looks like NASA managment is looking for an OK from the PP Officer. From the regulations NASA has accepted this is impossible if they want to do it anyway they have to go through COSPAR and a amendment to the rules. I hope they get this through in the year they have until they reach the RLS.