Three views from a pass of the International Space Station last night.
Taken in sequence, 22.20 GMT, 27 April 2011. Exposure 20 seconds at f.4, ISO500, 17mm on Canon 7D.
The trail is starting to dim in the last picture, and disappeared completely over the next five seconds.
To find out when the ISS is next coming over, I get Twitter alerts from Twisst.
With a diameter of 120,000 kilometres and a bright reflective surface, Saturn is an unmissable object in the night sky right now. But at 1.3 billion kilometres away from us, it looks only a hundreth the size of the full moon. Which means the screen width of my Saturn video below represents one third of a lunar diameter across (for best view, click to full screen):
[jwplayer mediaid=”9786″]
I recorded the movie through my old but capable 1978-vintage 6″ Fullerscopes reflector – specially resurrected for Easter after 30 years in storage. (See my efforts with the moon and the smaller ETX-90 telescope in Armchair Astronomy.)
Getting the telescope up and running really required nothing more than (literally) brushing away some cobwebs and giving the mirrors a wash – something I’d be more hesitant of doing had I not just read a step-by-step ‘how to’ in Sky at Night magazine.
Although thick with dust and grime, I’d reason to believe the mirrors’ coatings beneath were o.k., as I remember having them vacuum re-aluminised and silica coated just before I abandoned the instrument and disappeared off to university. Some gentle soaking, swabbing, and rinsing down with distilled water, and all was shiny once again.
Fullerscopes’ german equatorial mountings were all built like tanks – this ‘Mark II’, rated to carry a 10″ reflector, is still in good order save for some rust on the exposed steel shafts.
The RA drive, that ordinarily would drive the telescope counter-rotational to the Earth’s axis, wasn’t operational for a variety of reasons; but the fine adjustment on the declination axis was working.
All of which goes to explain why on the clip Saturn appears to fly across the screen.
I’d forgotten how stunning to the eye Saturn is through this telescope. In better seeing conditions I’ve seen the gap in the rings – the Cassini Division – quite clearly. Now, Saturn’s moon Titan was unmistakable.
Filming what you see with your eye is a little more challenging, although the ‘live view’ on the Canon 7D makes life a lot easier. Rather than watch the live feed through a computer, on this occasion I used the camera’s LCD display directly to focus with the help of a magnifying glass. The clip was made by projecting the image onto the camera’s CCD sensor via a 12.5mm orthoscopic eyepiece; the main mirror’s focal length is about 1250mm. The scene could have stood higher magnification, but I was limited by the eyepiece focal length and size of the projection tube.
All in all, considering the state of the equipment at the start of the day, I’m happy with the end result. The gap between the disk of Saturn and the rings is clear enough; but no Cassini division – so still some work to do! All the same, a fun day messing around with telescopes and engineering – no better way to spend the Easter hols.
2. To be exact: the angular size of Saturn on 25/4/2011 was 19 seconds (“) of arc, approximately a third of a minute. There are 60 seconds in a minute, and the moon is typically 30 minutes across; so Saturn appears one ninetieth of the moons diameter.
The Royal Society for the Protection of birds (RSPB) says: “the normal clutch size for mallard is 12 eggs, laid at one to two day intervals.”
Which makes the mother of this 16 strong brood paddling past our appartment yesterday something of a dynamic duck.
I’ve heard the record is 21 – so she still has a way to go. Impressive stuff all the same!
Through a combination of photography and a creeping fascination with avian behaviour and taxonomy (thanks to my wife giving me Colin Tudge’s The Secret Life of Birds for my birthday) I think I’m turning into some sort of accidental ornithologist. Point being, you can expect the occasional photo-flavoured birdy post; and today – it’s woodpeckers!
The female Eurasian Green Woodpecker (Picus viridis) above is one of the three most common woodpeckers found in the UK .
Photographically, woodpeckers are a challenge. The whole family is jumpy, taking off as a matter of principle at the sniff of a threat. So, considering I was sneaking up with no hide, I’m pleased how these turned out. Here are a few more of the male/female pair and a juvenile. You can tell the male by the red flash under his eye (click thumbnail to open slideshow):
And this male Great Spotted Woodpecker (Dendrocopos major)was snapped only a few days ago (click thumbnail to open slideshow):
Globally, there are 218 species4 in the Picidae family to which woodpeckers belong, living in every country with trees except for Australia and New Zealand.
Here are two more I snapped in California. The first set shows an Acorn Woodpecker Melanenpes formicivorus and the Ladder-backed Woodpecker Picoides scalaris (click thumbnail to open slideshow):
Here’s a video of a female Ladder-back hunting for bugs:
Acorn Woodpeckers are expert at turning trees into communal larders or caches. Pecking thousands of small pits in a single tree, they’ll place an acorn in each one – ready for harder times.
This set, again taken in California, is of a female Williamson’s Sapsucker – a member of the family specialising in eating the sap out of small wells drilled into the bark of pine trees:
Woodpeckers are a wonderful showcase for evolutionary adaptation.
Sharp claws set on toes laid out in the zygodactylous pattern – two toes facing forward, two back – are ideal for tree climbing. (Parrots and cuckoos are set up similarly, and elsewhere in the animal kingdom – Chameleons.)
Then there’s the way they hold themselves on the tree trunk.
Like rock climbers and photographers favour three points of contact for security and stability, woodpeckers have evolved a stiff tail to brace against the tree trunk and make a sturdy triangle with their splayed legs. The Sapsucker below demonstrates nicely; you can see her two tail quills bending under the pressure.
Having formed this miniaturised drilling platform, woodpeckers set-to doing their thing, which for a Ladder-backed woodpecker is banging its beak into bark and wood at up to 28 times a second, repeating the act several hundred times a day1.
The aim is to locate and consume insects and sap from under tree bark, a task for which their long, barbed tongue is well suited. But as this Great Spotted demonstrates, the birds are not above pecking the ground if there are bugs and termites to be had.
As hole-dwellers, woodpeckers also peck to hollow out a nest – a process that can take up to a month and involve the removal of tens of thousands of wood chips4.
For me, the woodpeckers’ most impressive adaptation is the multi-element shock absorber system that’s developed in and around its skull to prevent brain damage from all that bashing.
The full complexity of the system has only recently come to light. X-rays of a woodpecker’s head showed that the massive deceleration occuring at beak strike is cushioned and spread out thanks to elasticity in the beak, a spongy area of bone at the front of the skull, and a further special structure – the Hyoid – that directs pressure from the rear of the birds tongue around the back of its head1.
Well that’s a wrap on woodpeckers for the moment. Next phase is to try and catch these guys on HD video; they’re doing some great little courting dances this time of year. Reaches for camouflage gear….
References and further reading
1) A mechanical analysis of woodpecker drumming and its application to shock-absorbing systems. Sang-Hee Yoon and Sungmin Park 2011 Bioinspir. Biomim. 6 016003 IOP Publishing doi: 10.1088/1748-3182/6/1/016003
2) Digital Morphology. (Images at: http://digimorph.org/specimens/Melanerpes_aurifrons/)
3) Birds of Europe. Mullarney, Svenson, Zetterstrom, Grant. Princeton University Press, 1999. ISBN-13: 978-0-691-05053-9
4) The Secret Life of Birds. Tudge, Colin, Penguin, 2008.
5) Cornell Lab of Ornithology – All About Birds (Woodpecker page)
Also of interest?
I haven’t yet read James Gleick’s latest book Information, but was glad of the chance to hear him in conversation with Nico MacDonald at London’s RSA yesterday for a flavour of what’s in store. This is a brief write-up of my notes and some observations – it’s not a book review! (That may come later…)
The broad discussion covered topics ranging from the history of Information Theory, how new communications systems and technologies come about and how they’re applied, the rapid pace of developments, and related issues around information quality, choice, control, value, and authority.
Information Theory
Gleick introduced the father of Information Theory, Claude Shannon, who, building on foundations set down by George Boole and Alan Turing, developed the first mathematical theory of communication and the idea that information is measureable – in ‘bits’.
His approach of separating information from meaning in a structured scientific way was another first, launching a way of thinking that has since fed into all areas of formal communications and training.
Shannon’s ideas evolved out of work addressing real-world communications engineering problems at his employer Bell Laboratories, while other developments in information theory were driven by military objectives like those related to the codebreakers at Bletchley Park and the communication needs of the Cold War.
Development and Impact of the new
Gleick believes new technologies and systems appear first, followed by a series of highly unpredictable applications. Who, for example, would have thought the recently invented radio would play a critical role in capturing the murderer Dr. CrippenSee Note 1. Escaping to America by boat, Crippen was intercepted and arrested in Canadian waters after a wireless telegram exchange with the British Police.
But do new ideas and technologies just appear? Gleick argues that intellectual invention happens when the time is right. I’m not 100 percent clear on this, but he may have been referring to times of inspired national growth, and/or where intellectual groundwork has been done in related or previously unrelated fields, as was the case with Shannon embracing Boole’s and Turin’s legacy. And once these systems arrive, says Gleick, it’s not unusual to see “all hell breaking loose”.
Consider the geographical reach and speed at which information jets around the world today. I trust he’ll forgive me for this in the interest of illustration, but when Nico MacDonald mis-pronounced Gleick’s name during introductions today (Gleick pronounces his name ‘Glick’), that little faux pas was broadcast live, archived for webcast, and picked up by at least one troublesome blogger :-). That’s what this web-enabled, multi-media, Googlised, Twitterific world will do for you. On the other hand, those same information systems do little to inform us how we should pronounce ‘Gleick’; it’s not like every textual instance is accompanied by a phonetic brief. (I got it wrong too, so I guess we’re all better people for the experience.)
It’s also apparent that the forms of knowledge we are comfortable with are changing. Gleick recounted the story of Zick Rubin, whose recent piece in the New York Times titled “how the internet tried to kill me” describes how Rubin found his own death reported on a wiki – something of a shock to say the least. As it turned out, the wiki itself wasn’t the culprit, but a printed directory from which false information had been drawn. Had Rubin not run his search, the directory’s failings would never have come to light, and at least the wiki can, and has, been corrected at the press of a button.
Choice and control
Whether it’s the phone, radio, or world wide web, Gleick believes we’ve always driven our communications systems for more efficiency. But now the new systems and tools are coming ever thicker and faster – tempting us, thrusting themselves upon us – with Ads!
This overload is forcing us to make choices: Do I sign up to this? Who do I follow / unfollow? What’s my decision criteria? As an audience member summed up: “Our attention matters and we should think more how best to mobilise it”.
Once again, a discussion at the start of the session is topical: this time on the merits and de-merits of in-session Tweeting. As you might expect in the spirit of an Information flavoured event, the RSA had laid on WiFi and a hashtag so attendees could Tweet from the meeting. But I don’t think Gleick, while playing along gamefully, was really up for it – suggesting it might distract us from the discussion. And while I fully support in-event Tweeting, he is of course dead right; it’s a self-inflicted distraction that needs self-management. I’ve come across similar mini-controversies concerning chit-chat and questions during presentations in virtual worlds.
Value, quality, filtration
Into the Q&A, and a discussion on the potential for information to add value and generate competitive advantage. The conclusion here is that Gleick sees value linked to overcoming new economic challenges, so: publishers exploring new business models for e-books, and newspapers “scared to death about Twitter” looking for ways to compete with free news.
And as to us being overwhelmed by the sheer volume of information – reliable and unreliable – that all these new systems are generating? Gleick thinks not, but only if we sort out faster methods of recovering quality information and making intelligent recommendations. Efficient suppliers of those sorts of services will find themselves in a growth business.
Authority
If the information is good and there’s one set of agreed facts, then conclusions will speak for themselves – right? Wrong, says Gleick, pointing to those who would resist the overwhelming evidence for climate change; and that small group of Americans who still dispute Obama was born on Hawaii.
Moreover, he worries we might lose science as an “authoritative, trustworthy, account” in a world – as MacDonald observed – where some people decide a position upfront, only then looking to science to back it up – the antithesis of the scientific attitude of finding out facts and seeing where they lead.
Age of the information zombies
O.k., no one even mentioned information zombies. But the audience did wonder if access to ‘too much, too easy’ information might stop us (and particularly students) from concentrating and analysing properly. I got the impression Gleick was sanguine on this, but with a note of caution given we don’t even know the full effect that replacing mental arithematic with calculators has had, never mind the impact of the full on info-fest that is Google.
So, that was pretty much it – a thoroughly enjoyable lunchtime.
And as you see, I’ve got my signed copy of Information. Hopefully some ‘bits’ will agree with what I’ve just written :-P.
Note 1 – Updated 14/4/11. There was a mix up over stories in the conversation, with Crippen being confused with the murderer John Tawell. In 1845, Tawell was captured at Paddington Station thanks to the new telegraph (wired) being used to signal ahead that he was on the train from Slough where he had committed the murder. I’ve filled in the correct later story for Crippen, which is an analagous example but for the wireless rather than wired telegraph.
Event Audio – The audio of the event is here at the RSA’s Website
Royal Society Vidcast – Gleick presented at the Royal Society on the following day. Here is the vidcast at the RS’s website.
Also of interest: James Gleick interviewed on CastRoller
It’s a good few years since I took a photograph through a telescope, so I thought I’d share my latest pics.
The moon’s been presenting itself as a nice late evening target in our Westerly outlook this week, so that’s where I’m starting. These two are the best of the bunch from the last couple of nights (click for bigger pictures):
And in this video clip taken by eyepiece projection, there’s quite a bit of detail visible in the Mare Criseum (Sea-of-Crises) at top left:
[quicktime]https://communicatescience.com/zoonomian/wp-content/uploads/2011/04/Moon_astro_7_4_11_eyepieceprojection2.m4v[/quicktime]
This longer clip shows a complete traverse of the moon across the field of view (no tracking):
[quicktime]https://communicatescience.com/zoonomian/wp-content/uploads/2011/04/Moon_astro_7_4_11.m4v[/quicktime]
I’m particularly pleased with how the videos came out, capturing the fleeting moments of still air you need to look out for when observing live by eye.
The rig is built around an ultra-compact Meade ETX-90 telescope, picked up when I moved to London 10 years ago as a more suitable replacement for my 6 inch reflector. All I’ve added is a connecting tube and T-mount to get the camera hitched up.
Strictly speaking, you don’t need a telescope for astrophotography. Here’s the Plough (Big Dipper) taken with a tripod-mounted standard lens:
And these shots of an Earthlit Moon and Venus are two of my favourites:
I’ve also had some luck in the middle ground using telephoto lenses, where the results have been surprisingly good: like these pics of a lunar eclipse, the International Space Station (ISS), and Jupiter with its moons; all taken with a 400mm lens – in the case of the ISS, hand-held:
18 megapixels of digital zoom helps resolve the ISS into something other than an unrecognisable blob.
But to resolve surface detail in objects like Jupiter, a true astronomical telescope is called for.
I started by simply holding my smartphone to the eyepiece. Not a disaster, but I lost fine detail and the moon took on a weird pinkish bloom.
Attaching a digital SLR directly to the telescope gave better results, with the camera’s CCD (Charge Coupled Device) sensor at the prime focus. I also experimented with an old Logitech webcam with the lens removed, but the background noise was too high and the small sensor size made for a very narrow field of view.
The Canon 7D gives a much nicer image, and can be operated totally remotely via the computer. Live images are fed to the laptop screen for easy focus and exposure control.
With the still pictures, I want to get to grips with the various image processing techniques for stacking multiple images.
Of course, none of this competes with the Hubble Space Telescope, but amateur astrophotography for me is more about the satisfaction of seeing what a particular instrument can do, and learning along the way more about the various objects I’m photographing.
After the moon, my next target is Saturn, with the goal of resolving the Cassini division in the rings; and Jupiter, where I’ll be happy if I can resolve the Great Red Spot.
I’m also planning to take some guided wide-field photos of deep sky objects like the Orion Nebula. But that requires dark skys and the telescope’s drives being sufficiently accurate and strong enough to support a ‘piggy-backed’ camera and lens. All for another day.
The immediate issue, as the videos show, is just how bad the ‘seeing’ can be when observing at dusk from a building that’s been baking in the sun all day. I need to find more open skys.
But for now, with the telescope’s motors whirring away on the balcony, I literally am the armchair astrophotographer.
This piece from last Saturday’s New York Times on food colorings and the influence of color on taste perception takes me back to a Wellcome Trust exhibition I visited in 20031
Hosted by the London Science Museum, the Treat Yourself exhibition included an artwork, ‘Chromatic Diet’, by French artist Sophie Calle, that reproduced the colour-based diet followed by a character in Calle’s book Double Game 2.
As I haven’t read it, the appeal of eating a different monochromatic dish each day of the week is beyond me. But Psychologists have for years studied the effect of colour on taste perception, exposing diners to the likes of green french fries, blue steak, and black spaghetti, sometimes under distorting lighting conditions.
And as the NYT piece underlines, for manufacturers of processed foods, colour is a powerful marketing tool.
Yet without any higher scientific motive, I like the idea of inflicting the chromatic diet (or something similar) on an unsuspecting dinner party, just to see what would happen.
O.k., probably lose some friends; but at least it’s mainly natural ingredients and looks quite doable. And having chickened out in 2003, I’m thinking in the age of Heston Blumenthal this might be the moment. Let me know what happens if you get there before me.
Here are the ingredients list for the dishes in the picture2:
Orange: Purée of carrots, Boiled prawns, Cantaloupe melon, Orange juice
Red: Tomatoes, Steak tartare, Roasted red peppers, Lalande de Pomerol, domaine de Viand, 1990, Pomegranite
White: Flounder, Potatoes, Fromage blanc, Rice, Milk
Green: Cucumber, Broccoli, Spinach, Green basil pasta, Grapes and kiwi fruit, Mint cordial
Yellow: Afghan omelette, Potato salad, Banana, mango ice cream, Pschitt fizzy lemon drink
Pink: Ham, Taramasalata, Strawberry ice cream, Rosé wine from Provence
References
This beautiful flower arrangement I stumbled upon today has got to be the world’s most colourful interpretation of the Atlas myth.
In Greek mythology, the punishment meted out by Zeus to Atlas for his siding with the Titans against the Olympians was to carry the heavens on his shoulders for all time.
We’re familar with the statues of muscular bearded guys kneeling under spheres – sometimes with the earth substituted for the heavens. And in her book and film Longitude, author Dava Sobel tells how as a child she was inspired by the Atlas statue outside New York’s Rockefeller Centre.
The Atlas arrangement by Sandy Hine and Anne Harman is one of many on display under the theme Myths & Legends at the annual Florimania exhibition running 1-3 April at Hampton Court.