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The Cliffs of Churyumov-Gerasimenko

There is a big science conference taking place in San Francisco this week. Scientists – astronomers, geologists, physicists, and others – journalists and educators from all over the globe will be gathering to present papers and share their research with their peers and the world. There will be hundreds of different talks and presentations, and even more posters for attendees to listen to and look at, and anyone with even a passing interest in astronomy is following the event on Twitter (#AGU2014) and other social media sites. This is from the event website…

Nearly 24,000 Earth and space scientists, educators, students, and other leaders are expected at this year’s meeting. In addition, members of the press, guests, and exhibitors will bring the total attendance to more than 25,000.

So, a Big Deal as you can see! And this is the week when the first real heavy science from the ROSETTA comet mission will be released out into the wild by the mission’s scientists, so we might… mightfinally get to see some of the fantastic images taken by the OSIRIS cameras onboard ROSETTA! We will do, surely; how can the mission scientists give a presentation without images? So, unless they’re going to insist that all their images are not reproduced after their talks, or if they show them but then flash those memory wipe pens the Men In Black use into the eyes of every scientist and journalist in the room, later today we should be able to see, finally, some of the wonders the OSIRIS team has been keeping to itself all these months.

I can only imagine how scared and excited those poor OSIRIS images are feeling at this moment. Having been kept chained up in the dungeon beneath the MPS HQ for all these months, in the cold and dark, only let out now and again to be drooled over by the OSIRIS team, a lucky few have been led back up the stairs and into the daylight, given a good hosing down and then dressed in smart clothes ready for their release. They should have been freed from captivity long ago, it’s been disgraceful and cruel, but hopefully by tomorrow morning the internet will be awash with them, and journalists and space enthusiasts alike will be able to appreciate the beautiful, close-up views of the comet’s gas and dust vents, crumbling slopes and steep cliffs the OSIRIS cameras have been taking. Can’t wait to see those, and of course I’ll share them here when they appear.

In the meantime, a couple of days ago the ESA team responsible for releasing the probe’s navcam images put out one of the best yet. If you didn’t see it, here it is…

Comet_on_10_December_2014_NavCam

Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0

Isn’t that a beauty? Some details from the ESA website: This four-image mosaic comprises images taken from a distance of 20.1 km from the centre of Comet 67P/Churyumov-Gerasimenko on 10 December. The image resolution is 1.71 m/pixel and the individual 1024 x 1024 frames measure 1.75 km across. The mosaic is slightly cropped and measures 2.9 x 2.6 km.

Again, full credit – and a huge Thank You – to the ESA team which puts out these images. Without them the mission would have faded into obscurity the day after Philae landed (and we should probably use that term loosely now!) on the comet.

Anyway, as soon as I saw that image I could see one area was just crying out to be cropped and turned into one of my landscape views – there was our best view yet of the towering cliff face on the inside of the small lobe…

cliffs ringed

Looking at that part of the image I could see that with a little work (which turned out to be a LOT of work, but never mind!) those cliffs could be isolated and their true magnificence brought out. So, that’s what I started to do, and some time later this is what I came up with… PLEASE click on it to enlarge it…

ciffs2

Isn’t that something? The view, I mean, not my work (which I will admit I am pretty pleased with). I think that is a genuinely stunning view… just imagine standing there, at the foot of those cliffs, with those huge boulders scattered all around you, craning your head back to look up at the wall looming in front of and above you…

Since I posted that image on Twitter and Facebook it has become very popular, with an amazing number of retweets and Shares, which is obviously very gratifying after all the work that went into it, but more than that I’m delighted for the ROSETTA and ESA teams who took the images and released them, because it just shows how much interest in and passion for the mission there still is “out there”. If only the OSIRIS team could grasp that, and had been sharing some of their images more regularly with us from the start, it would have made a huge difference. Oh well, after sitting on them for so long, they have no choice but to share those images this week, at the AGU in San Francisco. Can’t wait to see them! 🙂

A New Year Northern Comet…

Skywatchers in the southern hemisphere are enjoying quite a treat at the moment, as a comet – “Lovejoy” (yes, another one! Terry Lovejoy keeps discovering them!) – is just becoming bright enough to see with the naked eye from a dark location. Long exposure photographs taken through telescopes show it has a vivid green coma, and is developing a rather beautiful feathery tail too, making it look a lot like a good old-fashioned “broom star”, as you can see from this absolutely beautiful photo taken by ace comet photographer Rolando Ligustri

928fa309ea20409afd8f32492ad531c2.1824x0_q100_watermark_watermark_opacity-40_watermark_position-1_watermark_text-Copyright astroligu60

Comet Lovejoy is currently too far south for us northerners to see it; it never gets above our horizon…

now beneath horizon

…so all we can do is drool over the lovely pictures of it being posted on Facebook and Twitter from southern observers, like this one…

jeanette lamb

Photo courtesy of Jeanette Lamb, see bottom of image for details.

Oh, look at that…. beautiful photo Jeanette, well done! 🙂

So, the question many of you will be asking is “WHEN IS IT OUR TURN UP HERE IN THE NORTH????” Well, the comet is slowly moving northwards, but so slowly that it will remain hidden from us for another week or so yet, but I reckon that if it’s clear on Christmas Eve we might… MIGHT… get our first look at it then, and if it keeps brightening the way it is doing we might get to see a naked eye comet in our northern sky by the New Year. Fingers crossed!

Assuming Lovejoy behaves itself (which comets really don’t like doing) and doesn’t turn off, or fall apart, or get trampled to death by a herd of rampaging space unicorns, where do we look for it when it finally peeps its head over our horizon? And what might we see?

Firstly, the key to finding this comet is a constellation familiar to all sky-watchers, whether they live north or south of the equator: Orion.

orion lines

Orion is very easy to find for northern hemisphere astronomers at this time of year. You just have to go out at around half past seven, face the east, and it’s right there in front of you…

orion 730pm now

Seriously, with that hourglass shape, and the line of three blue stars across its centre, all of the same brightness, you can’t miss it, and it’s one of the few constellations non-astronomers have seen in the sky that they recognise, even if they don’t really know what it is.

As I said, the comet is going to track up past Orion, to its right, and will be in that part of the sky until the end of January, so even though we can’t see the comet itself yet it makes sense to get out and start familiarising yourself with this region of the sky now. Look for the bright star Sirius (actually the brightest in the whole sky) to Orion’s lower left, and two star clusters to its upper right, the V-shaped Hyades cluster, and the smaller, tighter Pleiades cluster. Good idea to learn the names of the brightest stars in Orion itself too. This simple chart will help…

orion area lines and names

The comet is going to first appear beneath Orion around Christmas Eve, but although Orion will be visible in the sky from around 7pm on that night, you’ll have to go out later – or stay out longer – if you’re going to see it then, because the comet will still be so far south that it won’t creep above our local horizon until half past ten, and will be at its highest for the whole night only an hour later. When it does appear, here is where it will be…

Orion comet 1130pm xmas eve

As you can see it will be very low, barely scraping above the horizon, so any trees or buildings you have on your southern horizon might hide it. At this point you’ll probably only see it if you can get somewhere quite high, above local hills and buildings, with a flat horizon, and no lights. Even then it will probably only look like a small smudge in binocs. It might be faintly visible to the naked eye, if we’re lucky, but I wouldn’t get your hopes up too much for that; there’s so much mist and murk just above the horizon that the comet will look dimmer than it actually is. But sweep the area shown with your binoculars, or small telescope, and if you see it, great! If you don’t, well, be patient… 🙂

In the days after Christmas Eve the comet will be a little higher each night, slowly moving up away from the horizon as it drifts beneath Orion and then up into the sky, heading (roughly) towards those star clusters. Here are some VERY simple finder charts showing where it will be…

collage comet

…but a little more detail would be nice, right? That’s why, last week, when I was out hoping to see the Geminid meteor shower (and managed to bag a few) I took photos of this area of the sky too, so I could make a realistic finder chart for the comet, showing its track across the sky. Here it is, I hope you find it useful…

wide s

See? It will track up from beneath Orion and move on up to the right of the constellation. Here’s a closer look at its track…

pano13 track dec 31 jan 9 50 percent

… but everyone, please bear in mind these are just “rough guide” charts, just good enough to help you look for the comet with your naked eye or binocs. Other, far more accurate (and far prettier!) charts are available online.

As it moves northwards, amateur astronomers who know the sky like the backs of their hands will be able to find the comet easily, hopping from star to star, but of you’re not familiar with the sky what do you do? Well, if the comet is visible to the naked eye, all you will have to do is look in that direction and look for a small, misty smudge, and that will be the comet. If Lovejoy isn’t bright enough to be seen with just the naked eye, you’ll need to sweep the sky with binoculars, which is harder than it sounds. You don’t realise how huge the sky is, and how many stars are spattered across it, until you sweep it with binoculars! And there are lots of faint smudges and puffs if light in it which knowledgeable amateur astronomers recignise as galaxies, nebulae and star clusters but look like comets to beginners. Luckily, there are a couple of nights when the comet’s location will be easy to pin down using stars in the area as guides…

Dec 31 midnight beneath Rigel

On New Year’s Eve the comet will very helpfully lie right beneath the star Rigel, so all you have to do is find that star in your binoculars and then slowly, SLOWLY, pan them down until the comet pops into view.

And then, a week or so later, when the comet will visible right after sunset, by the time the sky is nice and dark it will be at one corner of an almost perfect celestial triangle…

Jan 6 6pm triangle

Of course, if you have a smartphone, or tablet, you can find the comet’s position using any of the astronomy apps available. If you’re not a smartphone owner, there will be more detailed charts available online by then, too.

Ok, that’s where it will be, but what will it LOOK like? No idea, sorry, it’s impossible to predict that. It MIGHT be visible to the naked eye, and if it continues to brighten as it is doing at the moment it will be, but it might just turn off and let us all down… comets are good at doing that… so we’ll just have to wait and see. Will it have a tail? Don’t know, sorry! We’ll have to wait and see! All we know for sure is that it is coming, and will be with us in around a week’s time, so cross your fingers and hope Comet Lovejoy gives us all a New Year treat.

And if you want to have a go at photographing the comet, I have lots of advice about that on one of my other blogs, which you can find here

Right, that’s enough to get you going, I think. All being well, we should get our first look at Comet Lovejoy in a week or so’s time, but the weather will have to improve and the comet will have to behave itself, too. Keep checking this blog for more details, and updates, and if you’re on Facebook or Twitter there are lots of great comet groups and observers on those social media sites you can follow to keep in touch with developments too.