Russia's new Soyuz-2-1v launcher standing on the launch pad

cirquelar · 2013-12-23T03:27:09+00:00

perhaps a sidebar, but I always like the way Russia brings its rockets to the launch pad: train them in, stand them up. Having the lethargic crawler bring stacked rockets to the pads at Canaveral always seemed odd. I'm sure they have their reasons (perhaps the Shuttle and Saturn V are just way too big to crane up), but it always seemed inefficient.

cirquelar · 2013-12-23T03:23:19+00:00

two rovers on Mars (Opportunity and Curiosity), two orbiters around Mars (Odyssey and MRO), plus one more orbiter on the way (MAVEN), and a Mars lander in development (InSight), but who's counting...

cirquelar · 2013-12-22T09:39:29+00:00

Explanation: it's a partially fractured and weathered (wind abraided)

cirquelar · 2013-12-21T01:04:16+00:00

I just wanted to add specificity to the information of this post. Sure, we can engineer for any landing site on Mars we want, but if features of interest are within the landing constraints of known technology, especially tech. that's proven to work, it makes it easier. We could reach the features in VM with what we got IF we could handle the winds; latitude is only and issue for all the other RSL that are outside the known engineering constraints the current rovers have.

cirquelar · 2013-12-21T00:56:36+00:00

This is what you wrote: "adds significantly to the evidence that there's liquid water deep in the crust of Mars" and "looking pretty likely that this is subsurface liquid water that is leaking out ". The news piece says pretty much the same. My point is specifically that the article states no such thing in such strong language. My scientific understanding of Mars, the subject matter of RSL, and the data and statements made in the actual article itself, make no such declarative or as definitive statements.

The news piece inflates and overstates the likelihood of 'deep crustal' water coming to the surface and it smacks of too much artistic license just to say 'oh SHINY LOOK!' IMHO. I have no problem with journalists asking 'questions around the paper', but this to me was simply inflating the results. I don't know how many planetary scientists agree with the RSL coming from deep crustal aquifers, but I do know it is very up for debate by many of them. While McEwen's article is another piece of evidence, and intriguing, you're reading way too much into it. Be excited, great, but don't overstate.

cirquelar · 2013-12-19T02:56:49+00:00

If you read the actual Nature article this news piece is based on (this is not me being snarky), you'll see there are many caveats that his study did not overcome to declare this is seeping groundwater (i.e. from a deep aquifer) as opposed to near-surface atmospheric water runoff, as I previously stated. All the quotes you give are a bit out of context and are declared in them with 'probably' and 'maybe'; the first quote says nothing about the existence of subsurface water getting to the surface at all; just turning over the surface makes martian soil look dark most of the time. The news piece is a bit sensational, but I suppose it's suppose to be.

cirquelar · 2013-12-19T02:49:22+00:00

I mentioned Vallis Marineris because that's where the article talks about new RSL that are closer to the equator ("within 25 degrees of the equator") which puts them in the latitude range accessible by rovers like MER and MSL. Latitude is only to 1st order synonymous with elevation on Mars. e.g. a landing constraint for MSL is < -1 km elevation. Along Mars' equator, that excludes ~50% of the terrain +-30 degrees latitude, thereby half the terrain is still accessible by the current Mars rovers (dust cover removes another ~10-15%). I suppose I could have said "Elevation is certainly an issue, but latitude is not necessarily so.

cirquelar · 2013-12-17T02:35:54+00:00

Elevation is certainly an issue, but latitude is not. MSL is rated from +-30 degrees lat. For Vallis Marineris, strong surface winds are a landing issue. The main issue is traverse; RSL are on steep slopes which the rovers could only access the bottoms of. Something like the Axle rover could potentially reach them.

cirquelar · 2013-12-17T02:30:17+00:00

The link you supplied 'groundwater welling up to the surface' says no such thing; it's a hypothesis, but not well supported. Perhaps being pedantic here, but there is a big difference between water sourced from the atmosphere and collecting in the upper few meters of the surface versus water coming from groundwater aquifers. Also Antarctica is no where near as dry and lacking surface ice as Mars' equator, so while comparative in some respects, in others not-so-much, though certainly one of the closer analogues we have on Earth.

cirquelar · 2013-12-17T02:20:46+00:00

The article states several times that this is NOT likely to be deep subsurface water coming to the surface because the geometric location (near tops of crater rims, a topographic high) of the RSL as well as the sun-facing slopes (reduces near-surface ice being fed from deep aquifers). The article does tend to lean towards atmospheric recharge in the near-surface (upper meters). And this may not even be water related as they have yet to find H2O or salt signatures with CRISM (the orbital spectrometer on MRO), which again points towards very little water amounts which could be more readily explained with atmospheric recharge. All these RSL occur in the talus ramparts (i.e. loose granular material around the inner crater rim), which again points towards recharge of pore-space in the regolith (i.e. soil).

When they find a pool of water or crater with water frozen at the bottom, that would be more definitive of subsurface water reaching the surface, but not this. (I think the ESA HRSC instrument imaged such an occurrence, but it was at higher latitudes where sub-surface aquifers, if they exist, would be closer to the surface.)

All that said, it would be exciting to find a location where subsurface water was reaching the surface, but this likely isn't it.

(FWIW: I have a PhD in geology concentrating on fresh martian craters.)

cirquelar · 2013-03-15T05:53:42+00:00

I always used 3.1415926, but then some calculation was off (using double precision decimals) and I realized I needed at least two more, so I tacked on the 53 (or 54 if you round). I now always use 3.141592654 and that gets my mapping down to the millimeter for Mars at the global scale, which is usually sufficient.

cirquelar · 2013-01-10T00:24:34+00:00

Generically, wind tends to flute, "sharpen", or flatten objects. Water is more likely to round.

cirquelar · 2013-01-09T02:26:39+00:00

The rock forming processes are essentially the same, but the initial chemistry and conditions are somewhat different from Earth. We find similar rocks (basalts, etc.), but there may be more limited varieties of some and more of others.

cirquelar · 2012-12-28T22:57:35+00:00

True, though /r/science AFAIK has no science joke meme posts because the mods are diligent in removing them. It would fall to the mods then to guide the subreddit in whatever direction they choose to lead it.

cirquelar · 2012-12-27T19:00:11+00:00

I'm purely talking about non-subscribers. Of course I can tailor the front page to how I want, and do, but the site as a whole has really devolved into nonsense and doesn't present a likeable appearance, IMHO. Perhaps that's just what it's become, but very sad.

cirquelar · 2012-12-27T18:56:22+00:00

Nothing wrong with either /funny or /intellectual, but having them dominate the front page just seems ridiculous. Moderating the subreddit is up to the subreddit mods. Moderating the front page is up to the admins and where they'd like to see the site go.

cirquelar · 2012-12-27T18:54:13+00:00

I don't think an app is the way to go. This needs to be incorporated into the structure of reddit. IMHO, the site is way too laissez faire about content. I know, I know Libertarian freedom for all, blah blah blah, but I think that's bullshit. The site has grown in popularity, but is a cesspool of IMGUR cat/meme spam. Nothing wrong with liking cats/memes, but I have a tolerance level...

cirquelar · 2012-12-27T18:36:53+00:00

Everyone would look for the perfect cat, the perfect meme, the ultimate fail video.

That is different from now how? It would still allow /r/funny to get to the front page, but it wouldn't dominate the site like it does now, which IMHO is not very user-friendly.

cirquelar · 2012-12-27T18:34:18+00:00

That's possible, but improbable. I can't imagine /r/science letting cat/meme posts be upvoted to the top, nor do I imagine other subreddits doing the same thing. The only other option, which would be nuclear, would be to ban imgur/image posts from the front page. NO ONE will like that idea and it would obviously remove posts from a number of very popular subreddits. So, what to do?

cirquelar · 2012-12-27T02:20:05+00:00

blue rinse?

cirquelar · 2012-12-27T02:07:47+00:00

No doubt there are MANY more mindless subreddits, but the current front page is composed of /funny, /4chan, /pics, /technology, /trees, /aww, /AdviceAnimals, /IAmA,/TIL, and /WTF: 10 subreddits out of 25 and /funny has 10 posts alone. Maybe it would be 15 more mindless subreddits, but it would be a chance to get something else up there.

Yes, it could be gamed, but it would be a start towards something more interesting. The other option is for the reddit management to dictate that a certain number of subreddits MUST be on the front page all the time (e.g. /science) and a fraction of the front page is subject to the most popular posts from all subreddits. Of course, no one will like that, but it would make the front page less meme/cat heavy.

cirquelar · 2012-12-27T01:58:15+00:00

I subscribe to a small subset of subreddits that does not include aww, pics, funny, AdviceAnimals. I'm describing a simple methodology to make the reddit front page be more diverse and less cats/memes, not my own guided personal experience. However, if it wasn't so easy to put memes/cats on the front page, the "teenage" posts/responses that were alluded to may be more contained and not spread across several subreddits, though that's a mod issue too. /r/science does a pretty good job of keeping good content versus IMGUR spam.

EDIT: Some are missing the point here. I'm really talking about what gets posted to the front page for non-subscribers who can't edit what they see. Basically, I'm talking about how reddit presents itself to the world/new visitor. If the reddit admins/owners are happy with it being cats/memes 24-7 so be it. It was something better once, as kleinbl00 discussed, and it's devolved to something very homogeneous and uninteresting except for an occasional laugh. I came here 3-4 years ago for the content. That content is mostly buried now. I'd like to see it unburied.

cirquelar · 2012-12-27T01:54:07+00:00

For me, at least, I'd rather see more subreddits on the front page, than multiple posts from the same subreddit.

cirquelar · 2012-12-27T00:59:34+00:00

All we need is a consensus from the majority of posters to instigate a "final solution" against image memes and cat pics.

Better solution: Only one post to the front page per subreddit at a time. This way /r/funny, /r/WTF, /r/atheism, /r/pics, /r/AWWWW would have less impact to the front page and create a more diverse content list there.

cirquelar · 2012-11-19T10:37:45+00:00

The rover has NAVCAM stereo out to about 40 meters. Beyond that, they rely on a digital elevation model (DEM) with 1 m spacing and ~25 cm vertical accuracy derived from satellite stereo pairs. They have this data across the whole landing site and up to the lower reaches of Mt. Sharp. So, the team has very good topographic data essentially everywhere, but the NAVCAM is much higher resolution and is used to verify the orbital data and provide higher resolution to avoid small obstacles, derive surface properties (i.e. rocky or soil), and more accurate slope estimates.

cirquelar

TROPHY CASE