Methusalah's star

I'm composing a mail for His CeilingCatness at WEIT, but it needs work.

So far : 

A common attack tactic for creationists is general assault on science - which they frequently support by deliberate mis-reading of reports, and/ or mixing of data from different eras. As you well know.

A popular target is that in the mid-late 1970s some stars had their ages estimated up in the 10+Ga (giga-annum, billion years ago) age range, while measurements from the ground put the cosmic microwave background at around 6 to 7 billion years. Obvious fodder for the god-squaddies. "Science can't be right, therefore God!"

This factoid sometimes gets described as the "Methuselah Star" and variations thereof.

One of the particular stars involved, and the most extreme example is in the Henry Draper star catalogue https://en.wikipedia.org/wiki/Henry_Draper_Catalogue, number HD 140283 (catalogue data and references at http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+140283&submit=SIMBAD+search). This is a spectroscopic catalogue that was published 1918-1924. 19-teens era spectroscopy required relatively bright stars, and it should be no surprise that "Methusalah's Star" is quite close (parallax 16.1140+/-0.0720 milliarcseconds (from SIMBAD, link above) - translating to 62+/-0.1 parsecs, 202.4+/-0.3 light years. That's about the total thickness of the Milky Way's "disc" ; the Milky Way has a shape similar to a CD or DVD disc. Really quite close! Corollary : in the rest of the galaxy, there are probably a lot of equally old, if not older, stars.

Multiple measurements since the 70s have improved our estimate of the age of the universe (BOOMerang https://en.wikipedia.org/wiki/BOOMERanG_experiment, WMAP https://en.wikipedia.org/wiki/WMAP Planck, https://en.wikipedia.org/wiki/Planck_Surveyor), and converged on 13.772±0.040 Ga as the age of the CMB - which is about 370,000 years after the big bang ( 0.00037 Ga - compare with the uncertainty cited above). Obviously that no longer conflicts with the age estimate for "Methusalah's Star".

Having updated the age of the universe, and the distance to the "Methusalah Star", what about it's age? Well that has been updated too. (Arxiv link below) Unfortunately, stars don't come with "Best Before" dates, or even interesting sets of isotopes (which we can read at many trillions of km range), so estimating their ages is rather difficult. But that has improved even more since the 1970s then the age estimates for the CMB.

What initially attracted attention to HD 140283 - why indeed, the astronomers producing the catalogue considered it worth taking note of - is that it's spectrum contained very few, weak absorption lines for what the astrophysicists call "metals" (their jape is that anything which is not hydrogen or helium is a "metal" ; hilarious!). In the 19-teens that was just a datum. As the characterisation goes, astrophysics at that time was more "stamp collecting" than "science". However when Hoyle (and others) developed a theory of powering stars by nucleosynthesis in the 1930s and 40s, this both justified the value of "stamp collecting science" and provided a tool for understanding the ages of stars.

[explain stellar age modelling]

Need to keep the emphasis on nucleosynthesis and core heat production, not get side-lined into primordial elements.

Basket Katz

"Basket Katz" (Mikki) is a friend's cat. In Bavaria.

 The reason for his nickname is fairly obvious.

A human side to a giant

A Neil Armstrong Anecdote

I like my science fiction, so some years ago I made a strategic decision : one of the proven routes for a novice SF author to get known, and to get experience in writing, is to write short stories and get them published in a magazine. So I took out a subscription to Fantasy and Science Fiction - not necessarily the highest in the pantheon, but they were in danger of going under, so I thought - that's a decent punt.
I'm getting what I expected : some great stories, some poor ones, some tedious editorial (I do not need to read about yet another bloody werewolf-vampire romance!) and some great editorial. Though to be honest, I'm less than diligent about reading them when they arrive - I tend to chuck them into corner of the bookshelf and take them to the rig for bedtime reading.
So, I rip open an un-opened envelope on the plane to Gabon here ... and it's the Nov/Dec 2012 edition. Been laying on the bookshelf since just after we moved. Oops.
And there's a great little anecdote in the editorial about the (then recently deceased) first man on the Moon, Neil Armstrong.
Now, there's a lot of hagiography about the man. First Man on the Moon ; the Right Stuff ; fluffed his lines on the biggest outside broadcast in the history of humanity. But there's not a lot about the man himself - after he retired from NASA, he didn't do a lot of public stuff, retiring into the background. His second-in-command, Buzz Aldrin, has been more famous in recent decades, if only for punching out the lights of a Moon Landing Conspiracy whackjob. Way to go, Buzz! and give him one in the nuts from me!
But back to the Neil Armstrong anecdote. The editorial, as befits the last number for the year, looks back at major events of that year, including, unsurprisingly Neil Armstrong's death. Gordon van Gelder, the F&SF editor, then recounts the following anecdote of a more human Neil Armstrong, ascribing it to one Lucius Shepard, though it doesn't appear on Sheperd's website.

I kinda met Neil Armstrong once back in the late '70s. My brother-in-law and I ran a T-shirt company and we had a couple of lines we sold to museum shops and at science fiction cons and like that. We were coming back from a sales trip, driving through rural Ohio, when we spotted a sign advertising the Neil Armstrong Museum in some little town. What the hell, we said. Maybe we can dump some shirts, so when we got to the museum we sat down with the curator, who was also the buyer for the gift shop, and pitched the shirts. We had a kids' shirt that resembled the body of a NASA space suit and the guy bought about 7, 8 dozen of those, along with shirts that had maps of the moon and Mars, the big red spot on Jupiter, etc. I don't recall how the subject came up, but I asked the curator if Neil ever came around the museum and the curator said, "Oh, sure. He's here all the time. I think he's here now." I asked if we could meet him and he said that Neil wasn't big on meeting new people and besides, he was probably sleeping. "He likes to sleep in the lander," he said. "He spends a lot of time in there."

"The moon lander?" I asked.

"It's a replica," the curator said. "It's up in the Moon Room, on the second floor. You can go on up if you'd like. Maybe you'll see him."

We went up to the second floor. There was a walkway that ran across the building, a bridge of sorts, then a gap that separated us from the Moon Room, which was a display of a life-sized lander sitting on some pumice-like material, and in the distance some painted crater walls, lunar mountains, and a black sky with stars. It probably looked fairly real when the lights were off, but the lights were on full and it looked pretty fake.

We hung out for around five minutes and then gave up on the idea of seeing Neil.

We went back downstairs, finished some paperwork and had a cup of coffee with the curator. I said I thought it struck me as weird, Neil Armstrong sleeping in the moon lander. The curator said maybe so, he'd never given it much thought.

Before we left we ran back up to the Moon Room to try and catch sight of Neil...and there he was. He was standing on the ladder leading up to the hatch. A guy with buzz-cut hair was all I could make out. We waved at him and after a second or two he waved back. I had a feeling he'd been on the verge of leaving the lander, but after that one wave he ascended the ladder and closed the hatch behind him.

That's all there is. Not much of an encounter. I used to think I'd write a story about seeing him, but it never came to anything. I liked thinking about Armstrong sleeping in the lander, though, the kind of dreams he had there and all. It made him seem a lot more real than that BS one small step for mankind quote that someone wrote for him. And it makes his death go down smoother to imagine him curled up in that cramped space on his padded couch, on his way to somewhere no one else has ever been.

 Well, yeah. That's nice. Different to the run of the mill. I'm really going to have to make more of an effort to read things when they are new.
(There are some good stories in that number of F&SF. You can get a copy, or a subscription, from their orders page.)

Skye, June, 2010

A couple of years ago I had a great  break on Skye, doing some archaeology, some walking, a bit of wildlife photographing, and just generally having a good time.
I posted a photo album about it on FaceJerkOff at the time, but since I've been getting increasingly distrustful of their policies since ... well, since they existed, to be honest, I've been taking my content off there in fits and starts, and I guess now is the time to move that album off too.

Uamh an Ard Achadh - "Cave of the High Pastures", or "Tin Can Alley" in times gone by (the current farmers are much more appreciative of it than previous ones, who just considered it a trap for their beasts). A natural limestone cave which appears to have been used as some sort of ritual site in the Mesolothic to early Iron Age, with modification of the cave entrance by dry-stone dyking, probably ploughing (ritual? - earliest agriculture in the area?) and the deliberate (or at least, non-accidental) burial of valuable artefacts.

It's a bit hard to see (this is not a site report!) but the meandering path of the deeply incised entrance runs away towards the dig which is in material piled up behind dry-stone dyking at the downstream end of the entrance passage.

The area is just plain beautiful.

 That's a nice view to wake up to in the morning.

 The fluffy highland coo. About as natural to the area as humans are, and probably imported from central Europe with the "Neolithic Revolution" around 5000 years ago. but they've settled in well.

 On Saturday and Sunday, the professional archaeologists have days of rest, so I did the same and took a boat trip around the islands of the Inner Minch - the so-called "Small Isles". A sea-stack with very evident columnar jointing - basaltic volcanism.

 Sea fidos. Gurt wet slobbering blobs.

 Arf!

 Puffins - they hardly look as if they can take off, and it's a huge performance.

 Basking shark. Big shark, no teeth.

 From the "behind the wall" deposits. It needs conserving properly, but it's an iron spear head. In it's day, this was your Porsche, crossed with an Exocet missile. Or something broadly equivalent. We may not know what was the process of thought was that led to it being positively buried behind a stone wall in a modified ritual site (which had probably been in use for a couple of THOUSAND years by this point), but we do know that it was not an accidental loss.

 Archaeologists often complain about being presented with finds "out of context". This is what they mean by "context" : each of those little white tags labels a "context" - a bed of sediment whose relative date (compared to other contexts) can be determined by the "A-overlays-B" and "C-cuts-across-D" arguments of stratigraphy. It's bread and butter work to an archaeologist (and I'm up to the eyeballs in the same sort of work drilling my oil wells), but it's absolutely essential to getting a proper understanding of a site (or oil well). And with it, we can do things like this :

 These are wooden fragments, possibly from a turned or carved bowl, taken from one of the "contexts in the image above. They're large enough to probably give a good carbon date to the context from which they come. AND thereby, they constrain the possible dates for many of the other contexts on the site.
Then along comes some creationist dipshit and dismisses this sort of work with "the archaeologists are lieing bastards who are blinded by their science to the power of our great sky fairy". Well, fuck you, god-squaddies - you plainly do not understand just how much hard, painstaking, detailed work you are casually brushing aside just to make yourselves feel less insignificant than you are.
These dingbats really do make me seethe.

---

To de-seethe, another bit of Skye's improbable scenery. The Old Man of Storr. See it before it falls over!

 There's a famous fossil site near the Old Man. It's a "no hammer" zone, but that doesn't preclude one finding excellent fossils in the beach debris. However ... when the site says "check the tide tables", it means "do not turn up on a whim without the slightest idea of the state of the tide". consider yourselves warned.

Lybster oil drilling site. There's an oil well of considerable weirdness being drilled there. The interest and amusement are pretty esoteric though.

Diving in Benin

I'm trying to gather contacts about doing some diving in Benin. Same sort of deal as when I was in Tanzania last year, operations will give me a few days break in town.
There doesn't seem to be a lot of info. An article in Africandiver.Com from 2009 refers to a commercial diving operation in Cotonou harbour, which doesn't surprise me in the slightest. I'm following that up.
Another blog posts about diving with the same people in 2012 ... actually at about the same time that I was at ECO2 in Tanzania. And I'm following that up too.
Going from a visitor every 3 years, to one a year may not be exactly a thriving business opportunity, but it's also several hundreds of percent growth.

UPDATE : I eventually contacted the company, but he was very busy with regular diving work in Cotonou harbour, with no time or interest in providing fills or gear for amateur visitors.

Partial Solar Eclipse 2013-11-03 13:25 UTC

I'm back on a rig, for a different bunch to the previous people in Tanzania (who are continuing with their programme there).
This time I'm on the West coast of Africa. Several tens of miles off the coast, actually. This map shows (approximately) where. The boats are not exactly un-obvious, but there's no point in making the pirate's lives any the easier.

Google Map

Today, in between doing things in the office, we've had a bit of post-prandial (after eating, for those who don't speak "Classics") excitement trying to follow a partial solar eclipse. We're actually several hundred miles from the totality region (which made landfall in Gabon, between Port Gentil and Libreville), so we only got a partial eclipse, but it was still pretty damned good.
Unfortunately, I'd not done my homework, and so hadn't brought decent filtering equipment for solar photography with me. Mea culpa. So I had to bash together a filter to protect (one) eye, and the sensor of my camera. Sometimes the warnings about "eclipse eye safety" are a bit overblown, but it is true that you can hurt yourself, so a reasonable degree of precaution is sensible. (And apply rule #1 : if it hurts, stop doing it!)
So ... what had I got? The black rubbish bin liners on the rig ... are too opaque and the plastic is loaded with biodegradable starch grains, so they're no use as filters. (Pure plastic sheeting, if thin enough, can do a reasonable job, and you can stack layers to adjust the dimming. It's a bodge, and only a poor substitute for a proper filter. As you'll see.)
Then I realised that I'd got a pair of those cardboard "spectacles" for viewing "3d pictures" with.

Now, those filters by themselves don't do a lot of filtering - maybe a stop or two (transmitting a third to a half of the light falling on them). But they're complementary colours :

So the combination is much darker - 6 or possibly even 8 stops (transmitting a tenth to a twentieth of the light incident on them). It does impart a rather unhealthy hue to the photos, but it got the light into the right sort of range of intensity that the camera's auto-exposure could handle it. With a little help from being set into low-sensitivity mode by the user. (Yes, I did RTFM.)
So, results :

Lesson # 1 : flash is a waste of battery in these circumstances. And it's still (just) too bright. By eye I can see the bite out of the Solar disc, but it's washed out in the sensor. On the other hand, the sensor hasn't started streaking (charge leaking from one CCD cell to the adjacent ones, resulting in vertical or horizontal (depending on the wiring of the sensor) streaks of overexposure).
The netting around the helideck is obvious, and those blobs of cloud promise considerable dimming of the light as they pass across the Solar disc.

My next attempt to handle the overexposure : prop myself up against a convenient piece of metalwork, and zoom the telephoto lens to it's maximum. (It is left as an exercise for the reader to realise why I didn't bother trying to use the additional "digital zoom" in the camera.) It didn't really help much. The cloud probably helped more.

This is the same image, but with the contrast cranked up all the way, and the brightness scaled back to reveal the top couple of bits of the intensity range. The zone of most over-saturation is noticeably off-circular, and that is in approximately the correct orientation for the "bite" that the Moon was taking out of the Sun's disc. All I need is another stop or two.
The moral of this story : carry your bloody filters! I'm there in a technical sense, just. But, to be honest, the photos are crap.
So what else can I do? Wait for cloud. Take some photos of our little flotilla out here.Look to see if we can see the shadow bands of the totality away to the south.

Oh, look. Cloud!
And the cloud is dialling the exposure down.

I processed this image (offline ; you don't have time to do this in the real world. You do your exposure calculations in your head.) in exactly the same way as the previous one (contrast up by 127 bits ; brightness down by 126 bits) and even the eye of faith isn't needed, because there's clear evidence of the wolf Fenrir attacking the Sun.

And the cloud thickens more.And off comes the makeshift filter.

Time to blow trumpets and bong gongs to scare the wolf away!

Not the best photography in the world, but not too shabby for stuff scrabbled together at the last moment.

Strange thing on Mars

As you do, I was browsing the maps of Mars on Google last night (mars.google.com, as if you didn't know already) when I wandered across this odd feature
SW of Olympus Mons on Mars (use the "Visible" band of imagery). 

(Unlike Google's terrestrial mapping, the option to embed a map isn't provided, so here's a static screenshot.)

What is attracting my attention is the linear feature across the centre of the image. It's approximately radial to Olympus Mons.
It's coordinates are  Lat +17.486911 & Long -143.34960.

So, WTF is it?

Checking the Gazetteer of Planetary Nomenclature, I can't find anything listed with a formal name at (vaguely) those coordinates. The range of possibilities includes (sorted by latitude) 
Name                                               Diameter          Latitude             Longitude -->

Pangboche		10.16	17.28	226.6
Turma		6.68	17.31	108.11
Yala		19.65	17.37	321.42
Nutak		11.26	17.41	329.74
Banff		5	17.51	329.29
Nune		8.47	17.55	321.24
Marbach		24.74	17.65	111.03

(Sorted by longitude.) -->

Dokka		51.1	77.17	214.24
Lycus Sulci		1350.61	28.14	215.53
Gordii Dorsum		481.56	4.11	215.86
Amazonis Sulci		250.59	-2.15	216.29
Koval'sky		296.67	-29.56	218.46
Nansen		74.63	-49.92	219.58

(Note : the gazetteer uses a 0-360 range for longitude; -143 = 143 W = 216 E)

A reality check : am I looking at the correct regions? "Pangboche" is a feature on Olympus Mons  (named for a Tibetan monastery on the approach march to Mt Everest base camp). "Lycus Sulci" is an albedo feature spreading around the west and north-west of Olympus Mons. So, I pass the reality check, and I'm looing at the right ranges of names.
No matches. So no-one has given it a name previously.

 The next of NASA's suggested resources is  Map-a-planet : what can that tell me?
Well, the MOLA (Mars Observer Laser Altimeter) dataset indicates that this feature forms a modest topographic low. And the feature is visible in the other base maps too, which is a good sign (not an observing artefact then).
Moving on then to the USGS's Mars Geographical Information System (GIS) at Mars Global GIS I can check dimensions : it's about 140km long. Which is not unreasonable for a large dyke system (but I'm hypothesising ahead of data). 

There are also a number of other sub-parallel features in the topography and basemap data.

Well, that's where I am at the moment. There's a real feature there, but what it is ... I don't know. I can't find any names in the region, which suggests that it hasn't received too much specific attention. And I'll continue later. 
Continuing research ... Searching Google for related terms ... 
ESA have been looking at the O.M. aureole. Not in this exact area, but close (222° East and 22°North). See http://www.esa.int/SPECIALS/Mars_Express/SEM59O67ESD_3.html
http://www.esa.int/SPECIALS/Mars_Express/SEM59O67ESD_0.html ... pretties, but concentrated on landslip deposits to N and slightly E of my target location.
Searching for "mars olympus mons linear feature" ...  http://geology.geoscienceworld.org/content/27/3/231.abstract discusses the origin of the aureole, including evidence for slump faulting in the area. Not (particularly relevant).
http://www.solarviews.com/eng/marsvolc.htm gives an overview of volcanism on Mars, but nothing specific for this region.
nkma.ksc.nasa.gov/mars/mgs/sci/fifthconf99/6050.pdf"These features possess very narrow (~35 – 45 m) crestal axes, are more resistant to erosion than the adjacent terrain, show a lack of stratigraphy in their vertical faces, and have a “meandering” strike consistent with the characteristics of terrestrial dikes. Inspection of Viking Orbiter images suggests that some dike segments may be 100 – 150 km long, with maximum lengths >300 km." This study certainly shows dykes and they're in the appropriate area and scale. Includes mention of possible dyke interactions with groundwater leading to pyroclastics / phreatomagmatic eruptions. Which might give the colour changes.
 (file saved locally as "fifthcon99-6050.pdf") Some of these "pyroclastics" overlie lava flow edges.
www.lpi.usra.edu/meetings/lpsc2012/pdf/2186.pdf discusses aspects of the photographic interpretation of the landscape.
(Page 3 of this Google search ... and I'm being self-referential! wellsite-geologist.blogspot.com/2012/11/strange-thing-on-mars.html)
Sixth International Conference on Mars (2003) 3149.pdf : looks at debris glaciers - interesting, but not relevant.
Icarus 181 (2006) 388–407 : looking at more piedmont glaciation. Which is good,but is to the N of the area I'm interested in.



2012-11-22 07:00
Woke up and thought of "HiRISE swathes". Checked phone to find that @doug_ellison (one of the @marsroverdriver crew) was suggesting particular swathes. t.co/HXICl0em t.co/2qDzxgLc are the (shortened links) to swathes he mentions. (Side issue - why didn't this tweet appear in the computer feed, but is on my phone ... meh!)
Swathe 1, t.co/HXICl0em decodes to "http://hirise.lpl.arizona.edu/PSP_009502_1980", where "chriso" discusses that the "dark spots" appear to be in contrast to the general ground lightness, which is ascribes to the general ground being mantled by light-coloured dust while the dark spots have relatively dark "basaltic sand". (This gels quite well with what we saw a couple of years ago on holiday to Santorini, with some beaches being of "black sand" and others of creamy-white pumice fragments. There's more going on there than grain size and chemistry, but that's good enough for this range of viewing.) There are certainly variations in the intensity of the blue colour, which would look like a variation in the amount of light dust present (or in the effectiveness of dust removal - in this view, it looks more like a deflation basin to me, perhaps. I'm looking very much at the blue patch between the central pinnacle and the main hill, and at the area just west of the main hill.). "chriso" describes alternating layers of dark and light material, but only in the darker areas ; maybe s/he's looking at higher resolution data, but I can clearly see three light-dark alternations south form the central pinnacle, which extend towards the east of the shot. (I'm assuming, perhaps wrongly, that the image is displayed in north-is-up orientation. EDIT : that's confirmed by the footer metadata - N=up.) The footer also includes a context shot from MOLA imagery, which puts this at the West end of the chain of dark spots.
Oh, hang on - that top-of-the-page image isn't the science image ; that's hidden in the background which links to PSP_009502_1980_RED.browse.jpg (naming convention PSP = tool name? ; orbit number ; image number?) So, moving back on to the science image ... OK, now I see the "headline" image in the science image, and NOW I can see that the light-dark banding is more-or-less confined to the darker areas (it looks rather like Moire fringing to me - and looks like the light-dark banding is shallow-dipping undulating layering irregularly dissected). The appearance of a deflation area is enhanced, with deflation stronger around particular peaks, and particularly to the W/ NW of the peaks.

Swathe 2, t.co/2qDzxgLc decodes to "http://hirise.lpl.arizona.edu/PSP_003450_1975"
(OK, straight to the science image! PSP_003450_1975_RED.browse.jpg)
Oh yes, now that I've got my eye in, that's looking very deflationary  also the "Moire fringe" pattern of the light-dark alternations.

OK ; I'm convinced now that these are essentially "deflation features". With access to the HiRISE images, it's quite clear.
This still leaves the question of why it's particularly in this area that it's happening. I'm going to guess that there's a regular wind pattern here (there's a topographic feature associated). Perhaps katabatic winds descending off O.M. with some topographic channelling.

Looking at the raw HiRISE data. (Well, not RAW raw, but the RDR data set (flat-fielded and stitched together, maybe rotated to North-is-up too.) At 341MB for a randomly selected file, I think that I need to be a touch more selective.
Are there mirrors nearer than Arizona?

So, I've been bimbling around for a bit, not really sure what I'm looking for. But I'm getting closer to a (data) product specification.
Having come across the original interesting feature by browsing on Google Mars, the obvious way to follow up would be a similar graphical interface that would display the footprints of the various imagers (and other data sources - landers) onto the image/ topography base map. Whether the GUI is directly linked to the source data is another issue (lots of different formats, I'll bet), but simply knowing "this area has been imaged by mission X (at time Y)" would narrow down the search space greatly. (which would mean fewer "WTF is that" conversations)
I see that the "submit-a-request" section of the HiRISE http://hirise.lpl.arizona.edu site does something along these lines already. ... And that's the only such site that I've found so far. ... OK, got myself an account. So, seeing target suggestions, HiRISE footprints, CTX, CRISM and MOC footprints.
Just as an eyeball ... what's the coverage? MOC, several % ; CRISM another % or so ; CTX is close to 100%, maybe a bit over ; HIRISE another % or so. (These are for the area W of and including OM.) It's a bit slow on the browser, but it tells me WHERE there is data, and the (it's a Google-Maps based tool) annoying little push-pins link to the actual science image (making them not-annoying!)
OK, I can see a (convenient) link to high-res data. And previously I've seen that it is common (required? I wouldn't be surprised) for the source image to be cited in papers based on it ... so my next task would be to collate (and collect, why not?) a list of images over the area of interest, and then search for papers that cite those. Without a science library, I'll have a choice of Google or something else. But that should be sufficient for my purposes.

AAIB reports relevant to the Bond crash.

I'm a bit worried - well, a lot worried - by the recent crash of a Bond chopper. I'm even more worried by the way that the same helicopter had suffered a engine vibration event several weeks ago. Was it associated?
I'm wondering if there are other cases of airframes that have been in incidents, and then later in a more serious incident. I've snarfed a lot of AAIB reports and am working through them to build up a database.