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Looking back at Huygens

Big space anniversary today which will probably go unmarked by the media, as they scrabble to fill pages and airtime with the latest Trump stories and reports of NHS misery: twelve years ago today the Huygens lander, carried to Saturn by the Cassini space probe, set down on the surface of Saturn’s largest moon, Titan.

Titan was the classic enigmatic, mysterious moon, one of the most mysterious places in the whole solar system. The size of the planet Mercury, Titan is big enough to be visible from Earth through a small telescope or even through a really good pair of binoculars, looking like a tiny “star” close to the Ringed Planet.

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Photos taken by the Voyager 1 space-probe as it whooshed through the Saturn system in 1980 showed the moon’s surface was hidden beneath an opaque atmosphere of thick, orange, smoggy gas, so the Huygens team had no real idea of what Titan’s surface was like, and the probe was designed to cope with various possibilities. In the end, after floating down through Titan’s atmosphere on a parachute and sending back breathtaking images of what were obviously – and unexpectedly, the channels of rivers of some sort, and the shorelines of lakes – Huygens  touched down on fairly solid ground, and before it perished in the unimagineable cold returned images from the surface showing it was surrounded by rounded pebbles of water ice, on a gritty beach-like surface.

I remember the day well. I was up in Cockermouth, visiting my mother who lived and still lives there. and I had arranged to go and give a talk on astronomy and space exploration to a class of kids at the junior school which is – literally – a stone’s throw away from my mother’s house. It was a “Tour of The Solar System”, looking at each planet and major moon in turn. I was a bit distracted during the talk, to be honest, because my head was full of thoughts of Huygens – would everything go ok? Would it take images on the way down as planned? Would it land safely? Would we get to see Titan’s surface? – but it was exciting to be able to tell the kids during the Saturn section of the talk that right then, at that very moment, a space probe was dropping down through Titan’s atmosphere and taking photos which would be on the news that evening. History in the making, as they say, because this would be the most distant landing every attempted by us. We’d landed lots of hardware on the Moon, and on Mars, but never on anything as far away as Titan…

It was a long and very frustrating wait for the images to appear online, and in those days ESA was nowhere near as generous or speedy with its image releases as it is now, so I spent a lot of time with my laptop on my knee, checking, re-checking and re-checking for images until finally, FINALLY, one appeared…

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At first I wasn’t sure what I was looking at… the horizon was blurred, out of focus, and those objects in the foreground looked like stones, or rocks of some kind, but without any sense of scale, or colour, it was difficult to get too much from the image. But that didn’t matter – that was TITAN! That was the surface of Titan, the largest moon around the Ringed Planet, the moon I had seen through my own little telescope so, so many times, as a “star” close to the rings… It was a genuinely moving experience, being able to see those images as they were released. Titan would never be the same again for any of us who were “into” space or astronomy. It truly was a world, not just a moon, not just a speck of light in an eyepiece.

Later, a colour version of the image appeared, and that was when many of us fell in love with Titan…

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It looked a bit like Mars, or Venus, but was obviously not either of those worlds. It was a world in its own right, a world that, from that day on, would call out to us from across the solar system like a siren.

Amazingly it was clear that night, I remember, so I got out my telescope, set it up, and looked at Saturn, which was well-placed for observation, already above the eastern horizon at sunset, and obvious to the naked eye as darkness deepened, shining not far from the stars Castor and Pollux. Lining up on Saturn with the finder scope I looked into the eyepiece.. and there it was, Titan, a speck of light close to the planet itself. And yes, it was genuinely thrilling to see it on the same day it had been “conquered” by Huygens, and looking at it I remember wondering what the little probe looked like those hours after its historic landing. Was it now covered with dust or sand, blown on the wind? Had it sank into the soft ground? We’d probably never know. But to be able to stand there and see Titan through my little telescope’s eyepiece, and look at a photo of its surface taken just hours earlier, was quite something.

Since then Cassini has revolutionised our view and understanding of Titan, using its cameras and radar instruments. We now know that Titan has huge lakes, and winding, meandering rivers – not of sparkling water, like Earth, but chemicals such as methane. We know it has vast plains of dark sand dunes, blown and sculpted by the winds, and bright clouds swirling in its atmosphere. We know that, contrary to what science fiction illustrators had imagined in the years before Huygens’ landing, the moon’s atmosphere is too thick and claggy to allow Saturn to be seen from the surface, which is shame, because that had always been one of the most thrilling and romantic views thought possible from “out there”.

Today we know that Titan is essentially a planet in its own right orbiting Saturn, and there is a huge demand from planetary scientists for a return to Titan as soon as possible, so we can properly explore its lakes – perhaps with a boat, or even a submarine – and map its surface in greater detail, studying its mountains, valleys and lake shores with a dedicated orbiter or even a balloon which would drift around the moon, carried on its winds. We will return to Titan one day, that’s for sure, it’s just a matter of when.

But today is the day to cast our minds back to events twelve years ago, when a little probe landed on the most exciting, most bizarre moon in the whole solar system. There’s a fantastic video of the landing here, made from actual images taken by Huygens as it dropped through Titan’s atmosphere and settled on the surface.

If the sky is clear before sunrise where you are tomorrow morning (in the northern hemisphere, that is), you can see Saturn for yourself, looking like a yellow-white “star” very low in the south east at around 6.30am. And if you have a telescope you’ll be able to see Titan, looking like a tiny star next to the beautiful ringed planet. If you see it, spare a thought for Huygens, and all it achieved, a dozen years ago, and marvel at the thought that we have landed one of our machines on a world so ridiculously far away that it just looks like a tiny star through a telescope.

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Gazing at sand…

Weird title for what is generally an astronomy- and space-related blog, I know, but bear with me…

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There’s a fascinating exhibition at the Brewery Arts Centre here in Kendal at the moment. “Sandgazer” features magnified images of sand grains gathered from around the world, taken by artist and photographer Jenny Natusch. Stella and I went to have a look on Thursday, and I couldn’t wait to see it because I’ve been fascinated by this topic for as long as I can remember. And the exhibition didn’t disappoint. Some of the photos are absolutely beautiful – portraits of tiny etched fragments of glass, minute shells, miniscule shards of stone, all photographed through a high-powered microscope and their images blown up to allow every tiny detail to be seen. A lovely touch is the way that each of the sand grains photographed is actually mounted on the wall next to its photo, in a tiny display box, which really gives a sense of scale.

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What really caught my eye was how one ridiculously tiny grain, when magnified, looked spookily like Mars as seen from orbit… the contrast in scale there was quite mind-spinning..!  It inspired me to make this image of my own…

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If I had one criticism/frustration viewing the exhibition it was that there are no descriptions of what each object is – is this one a shell? is this one a piece of glass? I wondered as I wandered around – but I did also wonder if maybe that was the point, and maybe they’re on display purely as objects of beauty, not there to be classified or labelled?  Turns out I was right: Jenny kindly explained the reason for the lack of labels in a reply to me on Facebook…

To answer your question……you guessed right…..I am not interested in labels, there are so many scientists doing that already, and some how it takes away the magic of it all to know what something is! Likewise, instead of giving the magnification I would rather display the grain next to the image.

Fair enough! Probably just me being my usual over-inquisitive science self. The lack of labels doesn’t take anything away from the exhibition at all; it really is fascinating, and the images themselves are beautiful, and, I’ll be honest, far more to my taste than some of the exhibitions the Brewery hosts. I know, I know, art is a very personal thing, not everyone can (or should) like the same thing, and every artist sees the world in their own unique way, but personally I can’t appreciate anything too abstract or “out there”, and sometimes I wander around the exhibitions at the Brewery in a state of bemusement, disbelief and utter confusion, not “getting” at all how… that… is “art”. This gripped and inspired me though. Maybe it’s because I’m someone who appreciates the beauty of rocks anyway; seeing these teeny tiny objects seemed very real to me, much more real than a few wispy brush strokes on a canvas that are supposed to represent the angst of modern existence… or something… 🙂

Walking around the photos you’ll think you’re seeing alien monsters, huge chunks of rock, glittering shards of magical gems, even a huge glowing nebula seen by the Hubble telescope… but every image is a portrait of a speck of matter, some less than a millimetre across, picked up off a beach somewhere in the world, just like the countless millions you’ve walked on or kicked into the air or patted into castles while on your holidays in Blackpool, Benidorm or Bali.

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“Sandgazer” is currently on display at the Brewery Arts Centre in Kendal, and is free. Go see it while it’s there!

More information: “Sandgazer”

A “star crash” in 2022…?

Ok, so this epic “star crash” predicted for 2022… sounds fascinating, and if it happens it will be a) very interesting to see, and b) a great success for the scientists making the predictions. But there is SO much hype about what it will look like! If you read some reports online it will be “dazzling”, or “blazing”, or “as bright as one of the brightest stars in the sky!” But if you take a moment to read the actual predictions, the astronomers are predicting a maximum magnitude of 2… which makes it as bright as Polaris… which is not really that bright at all (although many people think it is the brightest star in the sky) or one of the stars in The Big Dipper, which are all roughly around magnitude 2.

Now, that means that IF this star suddenly appears in Cygnus it will be very noticeable to astronomers and sky-watchers, who know the patterns the stars make up there so well they will instinctively realise that Cygnus looks… wrong… But non-astronomers will not have their gaze drawn to it, it won’t be bright enough to do that (although if it is a “red nova” as it’s being predicted that will help people spot it, because there aren’t any other red stars in that part of the sky). They’ll have to have it pointed out to them. But that’s ok… astronomical societies and individual astronomers will be able to use this as a great outreach opportunity, I think. And we have plenty of time to prepare! But it will be very important to manage expectations: we have to be stressing from now that this is only a possibility, a prediction, and making sure people don’t expect too much, i.e. they don’t believe the hype and expect to see a new Venus blazing in the sky. And it will be important, when 2022 rolls around, to help people see it if it appears, because it will be something very new and exciting – and handle their disappointment if it doesn’t.

I think we need to handle this very carefully. If you listen you can actually hear the ghosts of Comet Kohoutek and Comet ISON stirring out there in the dark depths, reminding us what happened with them when they promised so much but ultimately let us down. But we’re up to it, as a community, I’m sure!

Below – a couple of images I’ve made showing how the “red nova” MIGHT look if it appears as is being predicted. The background image is a Milky Way panorama taken at Kielder starcamp back in October, and I’ve added the nova in the **approximate** position where it could appear. I’ve made it about magnitude 2, as predictions are suggesting, and you can see it’s not going to be “blazing” or “dazzling” at all. Fascinating, yes. But not slap-across-the-face obvious.

Discuss by all means, but please note this is just a bit of fun, I’m not passing judgement on the prediction, or predicting this is exactly what we might see

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