Autumn is a welcome time for us stargazers as the longer nights offer more opportunities for enjoying Scilly’s stunning skies. What’s more, as our climate retains that little bit of extra warmth as the nights draw in, we look forward to some toasty evenings up at the observatory without too many added layers! And if we do get chilly, we can retreat to our cosy warm room. We can even operate our largest telescope, the 14 inch Meade, from the computer in there! Not that anything quite beats looking at some of our skies’ wonders with our own eyes, direct from the eyepiece.
It’s been a brilliant summer for us in several ways. In our first 6 months, we’ve welcomed nearly 700 visitors. We’ve had some heart-warming feedback about both what we’ve achieved and our enthusiasm. It has been terrific showing off the observatory to visitors of all ages and giving some visitors their own astronomy ‘wow’ moments, hopefully which will inspire them to pursue this most rewarding of hobbies.
We always talk to our visitors about what makes Scilly’s skies unique, our chief attribute being complete lack of light pollution. We want people to understand what this means and why we’re in the dwindling 21% of the UK that still has pristine night skies!
We have had some terrific evenings of observing with still, clear nights, and have cast our telescopes on not just star clusters and planets, but distant nebulae and galaxies.
As we get further into autumn and winter, the last of the summer constellations drop out of view and new ones appear. Now is a great time to catch the rich heart of our Milky Way at its best. Constellation Cygnus, the swan, which can be reduced to the Northern Cross, lies smack bang across the Milky Way and offers a rich area of observing. Gorgeous ringed Saturn will still be viewable in much of September up until November in fact, albeit very low in the southern sky; and giant Jupiter’s hanging around our early evening skies. Both are magical seen through our observatory’s telescopes – reality sometimes is more wondrous than you can imagine!
While we’re open until the end of October, with our first ‘season’ under our belts, we can now look back – and forward – to think about what we might do differently next year. Opening twice a week has worked well for us, with sell-out Tuesday nights and more informal Friday afternoons for drop-in tours and sun-gazing. While we’d like to be open more, we’re still a small team of dedicated volunteers (though in the longer term, there’s potential for a paid job there!). It’s still the case that visitors not staying on St Martin’s need to arrange their own transport to us, which poses issues due to the inevitable night boating: but this is island life. There’s also my previous point about peak season on Scilly not being the optimum time for stargazing – we could put on extra dates but it wouldn’t get dark any earlier, nor could we guarantee clear weather.
You’ve got until the end of October to pay us a visit in person. Then it’s our chance as a team and an island community, over our first Winter with our kit all up and running, to have a good play and build our working knowledge. One of the best things, however, about astronomy, and indeed running a community observatory, is that you can never know it all!
A version of this piece was originally broadcast on Radio Scilly in September 2019.
September is well and truly upon us and for us eager astronomers, this month marks the beginning of the new stargazing season (...handily, just as the tourist season on Scilly winds down and things get that bit quieter – less haring about between multiple jobs and still squeezing in open nights at the observatory!).
That ‘start of the stargazing season’ is less to do with what’s up in the sky but more that we’ve now hit meteorological autumn and the nights are getting longer: and you know what that means: more time for observing! In terms of what’s up there to look at, nothing’s massively changed since last month. Just that we can now see it by 9pm, cloud permitting.
I say the sky is much darker now, but for the next week and a bit, the very bright Moon, which is rising in the evenings, presents a bit of a pain – certainly when for looking at deep sky objects or indeed anything more than planets! – it can wash out all but the brightest stars up there. The Milky Way will also be less visible with the naked eye. The full Moon peaks on 14 September. While this means we can leave torches at home if we’re off out late, we’re really going to have to wait until after the last quarter, on 22 September, to appreciate the richness of the month’s skies. Nothing to stop you having a good old look at the Moon: Patrick Moore would approve, and you don’t really need anything more than binoculars for this. Proper astronomers – by the way I’m not counting myself in this category here! – will tell you that full Moon is the worst possible time to look at the Moon through a telescope, particularly if you want to look in geographical detail at the seas and craters, because it’s just too bright! They’ve got a point, but it depends what floats your boat. Amateurs like us at COSMOS will gladly say pooh to that: we’ll be happy to point our telescopes at the Moon whenever it’s big and bright. I for one quite like the aesthetic satisfaction of seeing the whole disc through the eyepiece in all its glory.
As we inch further into autumn and winter, the last of the summer constellations drop out of view and new ones appear; this is particularly the case in the hours before dawn. At 7 and a half month’s pregnant, I’m frequently up and down in the night, and I make the most of this joy (!) by popping my head out of the window to see what’s out there! If you’re also up into the wee small hours, you’ll notice Taurus (the Bull) is back with its clusters of the Hyades and the distinctive smudge of the Pleiades. This is part of my favourite patch of sky which also features stick men twins Gemini and, below them, multicoloured Orion. These will get higher in the sky earlier as the months progress towards the end of the year.
Gorgeous ringed Saturn will still be viewable in much of September - up until November in fact – albeit very low in the southern sky, not an issue for us sea-locked islanders whereas it would be if you lived in a built up area; and giant Jupiter’s hanging around our early evening skies. After the Moon, Jupiter’s the brightest thing in the sky at the moment. Nearby Saturn will appear dimmer, and more orange-y, but will be viewable before its nearby stars. If you're unsure what you're looking at, it’s a good time to refresh your knowledge on a stargazing app on your computer or phone – Stellarium is our go-to on PC; I use Star Walk 2 on my phone, but others are available.
We’ve welcomed more than 700 people to the observatory since April, which we’re very pleased with for our first ‘Scilly season’, and we’ve got lots to think about for next year – more on that later. We’re relishing the chance to get some decent stargazing sessions in as a team over the Winter, this is now our chance to get to know the kit a lot better, so as best to show it off to you! Anyway, you’ve got until the end of October to join us on St Martin’s in person, more details on our website. Tuesday evenings fill up fast so you must book ahead, and Friday afternoons offer a good point to drop in for a look around if you’re passing, or staying on another island.
That’s all for now: I’ll be back in a couple of weeks, when the new Moon means we’ll have some darker starry skies to explore.
A version of this piece was originally broadcast on Radio Scilly in August 2019.
We’ve had some delightful evenings stargazing in the last couple of weeks, with relatively cloudfree skies – and a late-rising Moon – meaning that between 9.30pm and 11.30pm (ish) there’s been a nice window for observing. By that I mean before the very bright Moon pops up and wipes out all but the brighter stars up there.
At this time of year the Milky Way arcs brightly across our sky. It’s something many visitors to Scilly come to marvel at and appreciate, thanks to our naturally dark skies here. It must be stressed that you need dark minimal light pollution to stand a chance of seeing it clearly, which wipes out much of the mainland! Indeed a recent report by the Campaign for Rural England warned that many children in the UK risk growing up never seeing the Milky Way, because of the damaging effect of artificial light on the night sky. Unless they live in rural areas, and that’s a real deprivation.
One sad fact is that England has only 21.7% of pristine, unpolluted sky left (even sadder is that most of these areas are sparsely or unpopulated – so go figure what the cause is).
Anyway, we treasure our dark sky here in Scilly and long may our nights gazing at the Milky Way continue. But what is the Milky Way and what are we seeing when we look at it?
The Milky Way is the galaxy that our Sun, and therefore our solar system, belongs to. In fact, all the individual stars we can see in our night sky are part of the same galaxy, the same Milky Way.
A galaxy is a group of stars, gas, dust, remains of stars, and dark matter, bound together by gravity. There are several different types of galaxy, named by shape. The Milky Way is a spiral galaxy, which means it resembles…a spiral. Following so far? Our Milky Way is somewhere between 150,000 and 200,000 light years across. So, very big then. You might at this stage be wondering how on earth we know all this. And the answer is, very clever guess work, scientific estimations – based on other spiral galaxies in space and observations of patterns of behaviour of the stars we can see. If you’re still doubting, you’ll have to take my word for it.
We are inside the galaxy, and as such we’ll never be able to see ALL of the stars in it. What we can see is a disk of stars that forms the Milky Way from inside the disk, which tells us that our galaxy is basically flat… but not much more.
Several telescopes have taken detailed images of the bar of the Milky Way, from different directions, and all have found a concentration of stars in a band in the middle, which adds evidence that we’re a spiral galaxy. Put it this way, if we were an elliptical galaxy, we’d see stars of our galaxy spread around the sky, not just in a single band.
At the centre of our galaxy is a dense bar-shaped cluster of stars, a veritable bulge, where most of the activity happens. And all the stars in our galaxy revolve around this galactic centre. It takes our Sun about 250 million years to do one full orbit so in terms of whether we notice the difference in our position, I’d say the answer is no.
Even though all the stars we can see in the sky are part of the Milky Way, the galaxy gets its name – no, not from the chocolate bar, the stars came first – but from how it appears as a milky band of light in the sky. So what are we looking at?
In short, that bright, milky streak in the sky, is what I’ve talked about: the bright, star-packed centre of our galaxy. Are we alone in it? Who knows. Give it a wave next time we get a clear night, and most of all appreciate how lucky we are to be able to see this wonder at all.
A version of this piece was originally broadcast on Radio Scilly in August 2019.
We’ve had lots of lovely visitors to our observatory over the last couple of weeks, and thankfully the skies are getting just that little bit darker, so that now by 10pm you’ve got a good selection of stars and planets to ogle at. This week we enjoyed a great session looking at the first-quarter Moon through our two biggest telescopes and spotting Jupiter and Saturn along the ecliptic.
Remember that it’s the busiest time of year here on Scilly and our sessions have proven to be very popular, so we do recommend you booking in advance, particularly for evenings, if you’d like to visit us in person.
The star event this week is not a star but the Perseids. The annual Perseid meteor shower reaches its peak on the night of the 12th August this year. If the weather plays fair with us, you should be able to see up to 70 shooting stars per hour, streaking across our skies. However we will be subject to a bright Moon causing us some light pollution, which will drown out the fainter ones. Don’t let this put you off though – the Perseid meteor shower is one of the best and most loved meteor showers in the northern hemisphere, for good reason. These meteors can be spectacular.
You don’t have to wait until Monday night to spot Perseids. We tend to focus on the peak of activity, entirely reasonable, but actually Perseids have been streaking across our sky since about the 17th July, and activity has ramped up from the beginning of August. You might have even seen some already! The Perseids tend to take a while to build up to a peak before falling off sharply – though we’ll still see them up to 10 days after the peak of activity on the 12th.
So what do they look like and why are they so special?
Perseid meteors are particularly bright and fast with lovely long trails. It’s one of the most active meteor showers of the whole year. There’s a particularly high chance of seeing fireballs – very bright meteors – as well. While they can be seen streaking across any part of the sky, they seem to radiate – or come from – within the constellation of Perseus, or, to my mind and somewhat easier to spot, below the wonky W of Cassiopeia.
Meteors in these annual showers come from streams of debris left behind in space, by comets. In this case, that’s Comet Swift Tuttle. As our planet Earth crosses the orbital path of Comet Swift Tuttle, bits of the comet’s debris slam into our Earth’s upper atmosphere at an average speed of 36 miles per second, burning up on impact. This force of energy causes quite the night-time light show from these fast-moving meteors.
And how best to view the Perseids?
The good news is that you don’t need any special equipment or knowledge of the constellations! Get yourself to a spot where you’ve got dark, open sky. Open sky is essential because these meteors fly across the sky in many directions and in front of lots of different constellations. On Scilly, finding dark and open sky is an easy one, but you’ll still want to take yourself away from any outdoor lighting or glare from house lights. You might want to lie on the grass - or beach - or get yourself a nice reclining deck chair with a blanket!
The weather for the peak of the activity this year is looking variable, though we may be lucky enough to snatch some cloud-free moments. The best time to look is towards midnight and after, when the chances of seeing increase. However, meteors are part of nature and there’s no way to predict how many you’ll see during any given period. Be patient. In any case, to get the best of it, give yourself at least an hour of observing time – and remember your eyes can take up to 20 minutes to adjust to the dark. Perseids can come in fits and starts and good things come to those who wait. Find yourself a good spot and relax – you’ll see some.
Let us know how you get on – and remember you can share any photos on our COSMOS Facebook group or email them to me at email@example.com. Enjoy those shooting stars!
We’re past the summer solstice which means only one thing for us stargazers: the nights are getting longer! Slowly at first, but by August we should have some precious extra time – before we get to the wee small hours – to enjoy Scilly’s beautiful dark skies.
Summer might be a glorious time to visit Scilly during the day, but by night alas you’ll have to stay out pretty late to make the most of our unpolluted sky. That shouldn’t put you off visiting us at the observatory when we’re open – as you’ll still get a good look round and we’ll make sure you leave with some top tips for your stargazing, if, that is, you don’t manage to see anything for yourselves. However, if you’re really keen to use the telescopes for some deep sky viewing, Autumn’s where it’s at. September through to November here on Scilly offer tantalisingly dark skies at far more reasonable hours and there’s still residual warmth in our temperatures to boot.
We’ve been treated to far this summer to some stunning glimpses of king of the planets Jupiter, gracing our southern skies. From our vantage point on St Martin’s, it’s been hovering above the Eastern Isles. Even a modest telescope can make out its rings of cloud and if you’re lucky, spot the great red spot. I’m sharing a picture of Jupiter and its four Galilean moons, taken through our smaller night-time telescope.
August is a prime month for gazing upon many people’s favourite planet, Saturn – he of the majestic rings. Saturn’s best viewed low in the southern horizon from the middle of August. It’s wonderful to view through our telescopes as the feted rings become tangibly real.
Also look out for the peak of the spectacular Perseid meteor shower around 12/13 August, when we’re expecting in the up to 70 per hour, whizzing across the night sky! For best viewing, sneak out pre-dawn when there’s a short Moon-free window, before the twilight appears. If you can’t rouse yourself for that, the Perseids should still deliver you some ‘ooh’ moments if you’re lucky at any time after dark. Perseids are often bright and leave visible trails. Look to the north-eastern part of the sky – they radiate (appear to come from) the constellation of Perseus. Enjoy!
A version of this piece was originally broadcast on Radio Scilly in July 2019.
I hope you’ve enjoyed the recent coverage of the 50th anniversary of the Moon landing, by NASA’s Apollo 11 crew. There have been some excellent documentaries on the telly about the mission that have reminded us just how exciting ‘the future’ of space travel was 50 years ago. 50 years feels like a long time ago when you think that even 20 years ago WiFi wasn’t even a thing and even 10 years ago lots of us didn’t even have a smartphone let alone an iPad! For perspective, Apollo 11’s onboard computer had about the same computing power as the fitness tracker on my wrist! Now it’s 10,000 small steps a day for man…
And yet, for all their worth, the Apollo missions didn’t usher in a new era of space travel. After Armstrong and Aldrin, 10 more men walked on the Moon before 1972 when the Apollo programme was wound up. The space race with Russia was, in many ways, more a political victory more than a scientific one. Though the science is remarkable. But NASA ran out of money, and 'the public' had already lost interest (imagine!!) by Apollos 15 to 17. No one since has stepped on the Moon nor any other world, and that’s not looking particularly imminent. We might now look to new superpowers including China – the only country so far to have landed on the dark side of the Moon.
At the Observatory we had a lovely open afternoon to commemorate the events of 1969, however we weren’t able to gaze upon the Moon that night – due to pesky cloud stopping play. The beginning of August actually offers a much better opportunity to fix a telescope on the Apollo 11 landing site – not that you can see any flags or footprints, even with a whopping great telescope ten times the size of our whopper here on St Martin’s. Still – the first few days after the New Moon offer brilliant Moon-gazing opportunities, from being the first to spot the new crescent to exploring the textures along terminator (the edge between the moon and shadow) as the Moon grows.
We’re also entering the start of the annual summer Perseid meteor shower. One of the best and brightest spectacles of the night sky. Sadly this is where we get the Moon even if we don’t want it, the Moon providing the only light pollution we can expect here in Scilly for the Perseids this year! Still, you won’t have to be too lucky to catch a shooting star. The peak (which is around 12th August this year) sees about 75 Perseids an hour. These shooting stars are renowned for their brightness and long, lingering tails. From the 1st of August, you should be able to catch some – in fact we’ve seen a few at our stargazing sessions on St Martin’s already. They radiate – appear to come from – the constellation of Perseus. But the easiest way in my book is to find the distinctive wonky W of Cassiopeia and aim your gaze around there. You might want a deckchair for this to save your neck!
If that’s not enough for you and you’d like to stargaze at an actual star, see if you can find Altair, in Aquila the eagle. It’s the lowest of the 3 bright stars in the Summer triangle asterism, well placed in the Summer sky at the moment. Altair is a lovely bright giant, flanked by 2 dimmer stars, making almost a straight line of 3 – not to be mistaken for Orion’s belt, that’s for Winter. As if there’s not enough to be looking up at, see if you can find these three, the family of Aquila for yourself in the next couple of weeks.
This piece was originally broadcast on Radio Scilly in July 2019.
The last fortnight’s glorious calm weather has given us some fantastic nights for stargazing. Many visitors to the observatory in the last couple of weeks have told stories of unbelievable skies (I believe them) later on in the evenings. Campers especially seem to be the lucky ones with late night toilet trips. One perk to sleeping under canvas if ever you needed one!
I have also been asked on one memorable occasion this week if I can make the sky darker during the observatory’s open hours, to which the answer, sadly, is no. This might be high season for Scilly but it’s low season for astronomers.
In any case, the nights are drawing in – slowly! – so by 11pm you’ve got near complete darkness. Better than nothing.
Now if there’s one planet that you must view through a telescope once in your life it has to be Saturn. Even the most die-hard, seen-it-all astronomer will still get a kick from viewing Saturn at this time of year. It really is a beauty. And it has an exquisite ring system, unmatched by any other planet.
Saturn has reached opposition this week – which in short means it’s as close as it gets to Earth all year. We’re talking a few thousand kilometres closer, which in the grand scheme of things isn’t far, so to be honest, all month is good for viewing! The best time to view is around midnight, when it’s highest in the sky. Technically it rises above our horizon around 9pm, but because of the lightness then, good luck spotting it any time before half ten!
Saturn can be spotted relatively low in the Southern Sky, at the moment, below and to the left of the very bright Jupiter as you’re looking. We’re lucky here on Scilly because it’s southern position means we’ll largely be viewing it above the sea, as low a horizon as you could wish for. Saturn’s not as bright as giant Jupiter – bear in mind that not only is it smaller, it is also twice as far away. But Saturn IS brighter than any nearby stars. You can tell this because you’ll see it with the naked eye well before any other stars come out. If you need any more clues to its identity, you’ll see it’s got a noticeably yellowish hue. I looked at it last night through my modest binoculars and could just make out an oval shape, which includes the rings. Add in a small telescope and you’ll see the rings clearly. A 14 inch Meade such as we have at the Observatory might blow your mind!
Before we get dark however there’s a super atmospheric phenomenon that we can witness just after sunset, in the name of Noctilucent Clouds – aka NLCs. These are the highest clouds on Earth and occur in a narrow layer some 80km up in the atmosphere. Because they’re so high up, they even reflect the Sun’s light during the hours of darkness. Noctilucent means ‘night shining’. The ideal time to look for them is 1 and a half to 2 hours after sunset, and to the northwest horizon. Alternatively, if you’re an early riser, look Northeast an hour or so before sunrise. Noctilucent clouds may look electric blue against an otherwise darkening sky. They’re very pretty and you’ll be able to spot them from now up until the start of August.
So there you have it - Saturn and Noctilucent Clouds – beauties to marvel at when it’s dark….and getting dark.
This piece was originally broadcast on Radio Scilly in June 2019.
Hello from the Observatory on St Martin’s. I’ve been wowed by the Moon rising a glorious shade of orange this week – it’s rising late at the moment, just before and now just after midnight. If you’ve been awake to catch it, you might well be awestruck – as I was – by its vivid orange colour. This isn’t what we call a blood moon, but a result of the Earth’s atmosphere. The colour occurs when the Moon is low in the horizon, because you’re looking at it through more of the Earth’s atmosphere.
That atmosphere is filled with particles that absorb and scatter light. In short, the longer the lightwaves, the redder they appear. So when the light from the Moon travels through more atmosphere, the Moon appears redder in the sky. It’s the same reason – in principle – why sunsets appear red and orange.
To other glowing wonders in the sky. You can’t miss glorious Jupiter at the moment, fairly low in the Southern sky. It might be hard to spot in a built up city but not here on Scilly with our long, low horizons. You’ll be able to see it with the naked eye anytime from 10 o’clock – even when the sky isn’t fully dark. At magnitude -2.5 or thereabouts it’s the brightest thing in the sky after the sun sets. And well after that.
When you look at it with the naked eye, or at least when I do, it seems a little orangey and very bright! Remember it’s much, much closer to us than any of the stars we can see, so its light isn’t having to travel so far. And that’s even light reflected by the Sun – Jupiter doesn’t emit any of its own.
A telescope even of modest proportions will show the planet as a flattened disc, and you’ll be able to see two of its darker bands of clouds. The Southern band of cloud is home to the famous Great Red Spot. Bear in mind that you might not see it as Jupiter’s always on the move – spinning once on its axis every 9.8 hours.
Jupiter’s the undisputed king of the planets. It’s a whopper, weighing in at 318 times the mass of the Earth. It also has some 60 moons, compared to our 1. Its sheer mass and gravitational pull are also thought to have helped bring the planets into the positions we see today. Mentally it can be quite hard to visualise the sheer scale of our solar system. So I’ll very scientifically use St Martin’s single road to help us out.
Imagine this: If the Sun was the size of a beach ball, balanced on the end of Higher Town Quay, the Earth would be the size of a pea, roughly at the top of the quay. Walking on, we’ll pass Mars (outside Higher Town waiting room, and the size of a peppercorn). We’ll then keep walking up until we reach the top of Par Hill as the road turns a corner – and there we’ll find Jupiter, the size of an orange. (If you’re interested in going further, Saturn’s outside St Martin’s stores, the size of a lime…. But I’ll stop there)
However you do it, or choose to understand it, enjoy gazing at Jupiter – it’s currently at its best viewing all year. Now… to fix those clouds…
This piece was originally broadcast on Radio Scilly in June 2019.
Hello again from the Observatory on St Martin’s. June’s not the best month for stargazing as you have to stay up so late! But that’s not to say it’s not rewarding when you do. We’ve had a mixed bag of night skies in the last couple of weeks, and a good few of those have been relatively clear.
As we inch towards the summer solstice (the longest day and shortest night), on 21 June, it doesn’t currently get truly dark until about 11pm. Even at half past 10, on a clearer night you won’t need a torch if you venture out. Here in Scilly, that’s due to our flat horizons with so much sea around, so the last light of the sun lingers on...and on.
Come darkness and some summertime beauties are yours to behold. Look to the East and you’ll spot a distinctive triangle of three stars of near equal brightness. This is known as the summer triangle. Its stars are Vega, Deneb and Altair.
I’ve mentioned Vega before, as it’s one of the brightest stars we can currently see and one of the first to pop out as the sky darkens. Vega forms the vertex (the top point) of the summer triangle. It’s part of the constellation Lyra, the harp, or more technically, the lyre. But Vega’s so much, much brighter than Lyra’s other stars, so you’ll need a good clear night to pick them out. Lyra’s shaped – helpfully – a bit like a lyre, with 4 fainter stars forming the body of the instrument and Vega at its neck.
Altair is the star of the summer triangle closest to the horizon and its part of constellation Aquila, the eagle. At a mere 16.7 light years away from us, Altair’s one of the closest stars to us visible with the naked eye. But it’s only the 12th brightest in the night sky, so it’s not as dazzling as Vega.
Deneb – our last point on the summer triangle - is fantastic star to spot as it’s a great waymarker to finding Milky Way. Deneb is part of constellation Cygnus, the swan. It’s a lovely one, this. Looking like a flying swan with its wings spread. The brightest stars in Cygnus form what looks like a Christian cross, hence it also being known as the Northern Cross. The Northern Cross lies smack bang along the visible streak the Milky Way. If you’re lucky to have a clear and dark night, you can’t miss the Milky Way – it’s not ‘light cloud’ you’re seeing in that haze – it’s millions and billions of stars!
Hopefully that’s given you a few things to find for the next couple of weeks. As I say, these are visible from 11pm onwards, so you needn’t burn the midnight oil dry.
We’ve been enjoying the The Planets, on telly on BBC2 every Tuesday evening, presented by Brian Cox. The last instalment took a fascinating look at Mars – our nearest planet. Once a watery world, now a barren, rocky land devoid of life.
If you’re interested, you can currently catch a glimpse of Mars, here on Scilly, from about 10 o’clock onwards. Look West towards the last light of the Sun, below and to the right of the rising Moon, close to the Western horizon. You’ll see a light red dot. Mars is nowhere near its brightest, and the light background of the sky doesn’t help. But if you want to glimpse captivating red planet for yourself, there it will be.
This piece was originally broadcast on Radio Scilly in May 2019.
Hello again from the Observatory on St Martin’s! I’m sat here in our warm room, which is the astronomer’s way of saying 'posh shed'. In short, it’s the space here at the observatory where we keep all the computer equipment and our telescopes when we’re not using them in the domes. It’s also where we come together to plan what we’re going to look at in the night sky at our stargazing sessions. We’ve got wall charts with the moon phases, maps of the sky and a big calendar for major events coming up. If you’ve visited us already, you’ve certainly been in here; if you haven’t, what are you waiting for? We’re open Tuesday evenings and Friday afternoons.
Many people have asked why we’re open during the day. Well, it’s a myth that astronomy only happens at night. Fridays are dedicated to solar-gazing. The Sun – our nearest and most important star – is all too easily forgotten as an object of astronomical interest! It can offer some of the most visually rewarding observations in astronomy. It’s also never been more popular.
On St Martin’s, we have a powerful solar telescope, with which we can observe the sun in detail with our very own eyes.
Now, before you fear for your eyesight I should say that solar telescopes like ours are sophisticated bits of kit, with the crucial bit being a very strong hydrogen-alpha filter which blocks out harmful wavelengths of light. This means you can look at the Sun directly. (Something you should absolutely never, ever do with the naked eye!)
So what can you see? Looking through the solar scope on a clear sunny day, the Sun appears as a red disc in the eyepiece. You can make out a dynamic, shifting surface, almost whirling before your eyes. If you’re lucky and there’s a period of high solar activity, you could easily find a sun spot or a solar prominence – shards of gas, shooting from the edge of the sun’s disc. All this activity has the potential to impact life on earth, which is why it’s a growing area of interest. Whether you spot any or not, it’s pretty exciting to look at our Sun, up close and personal. Where would we be without it?
To the night sky. We’re approaching the longest day of the year, and it doesn’t get truly dark here on Scilly until gone 11pm. A little too late for many of us – myself included – on a school night. That said, anytime after 10pm, on a clear night, I do enjoy looking up at the twilight sky as the first stars pop out, like distant lights, twinkling on.
The first you’ll probably see will be Arcturus, biggest star in constellation Bootes ('Booties' is the wrong pronunciation by the way – it should be Boe-OH-teez, from the ancient Greek for ox herder, but I always feel a little silly saying it that way, so I’m happy to be wrong). Arcturus is an orange giant, appearing dazzlingly pinky-orange in the southern sky. It’s about 170 times brighter than our little Sun and more than 36 light years away.
Look further East and you’ll spot Vega, in constellation Lyra, the harp. This one’s a mere 25 light years away. In 10,000 years, Vega will replace Polaris as the pole star! In the meantime, enjoy it where it is as part of our lovely – if not completely dark – Summer sky.