The Leonids

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The radiant of the Leonids is in the constellation Leo, but you don’t need to look in that directions to see shooting stars.

The annual Leonids meteor shower is due to peak over the weekend between 17 and 18th November 2018.  Although the waxing gibbous Moon will diminish conditions somewhat it will still be more than worthwhile heading out somewhere dark to observe them.  Over the peak as many as 10-15 meteors per hour may be visible.  Occasionally meteor showers will erupt into storms, as was the case with the Leonids in November 1833, when 100,000 meteors per hour rained down over an entire evening!

The shower is caused by the Earth colliding with the debris left behind by comet Temple-Tuttle, a short period comet with a period of 33 years.  Temple-Tuttle is due to swing past the Sun again in May 2031, when it will once again deposit fine dust trails behind it, seeding future generations of meteor showers.

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The tail of a Comet always points away from the Sun.  Debris from the Comet’s tail produce most meteor showers, as the Earth intersects the fine dust trails in its annual orbit around the Sun.

Observing the Leonids

You don’t need any special equipment to view a meteor shower, in fact binoculars or telescopes will just narrow your field of view. Grab a deck chair or a warm blanket, prepare a hot drink, wrap up warm and lay out under the darkest conditions you can find. It’s an excellent activity to do alone or if you have children they’ll love an excuse to get outside for some after dark play.

Put away any lights or bright mobile phones and simply look up and wait. Remember it takes up to 30 minutes for your eyes to fully dark adapt and any exposure to bright lights will start the process all over again. If you need a light red touches are best for preserving you night vision.

For optimal viewing, head out after the Moon sets, or in the darkness of the pre dawn sky.

Approximate Moon set times at Highland latitudes this weekend:

Friday night 12.30am
Saturday night 1.30am

You can still see meteors with the moon up but generally only the brightest ones. Early morning viewing will be optimal as Leo (the radiant) is high in the sky then.

Good luck and clear skies!

Meteor_falling_courtesy_NASA

World Class Darkness at The Torridon

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The Plough facing north from the grounds of the Torridon Resort

I had a great time with hotel guests at the Torridon Resort this weekend, stargazing under Bortle 1 class dark skies. We were clouded out on Friday evening but had spectacular skies on the Saturday, with galaxies in particular brighter than I’ve seen them before.

The Torridon Resort was the base of operations for this luxury astronomy break.  It’s situated in one of the most remote extremities of the Western Highlands, well within the Bortle 1 and 2 classifications for darkness.

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Stars appear at twilight, facing south from the grounds of the Torridon Resort

Our main excursions took us high above the hotel on the slopes overlooking loch Torridon, near Balgy.  On a previous scouting mission to find good observing locations I bumped into a nice chap called Nigel who owns self catering cottages in the vicinity, at ‘Baden Mhugaidh’.  He had kindly invited me to take the stargazing party onto his land over the weekend, and as we pulled the van up he joined us for some dark sky observing.

Although there were some thin clouds in the north and on the eastern horizon, overall sky quality and seeing was spectacular with the bright band of the Milky way on display overhead and vivid depth evident in the Cygnus region of the galaxy near Deneb and Vega.

Galaxies were popping with brilliant vibrancy in binocular views, with Andromeda showing bright lane detail and Bodes galaxy in Ursa Major clearer than I’ve ever seen it in field glasses.

We took in a tour of the main constellations, including the beautiful clusters in Perseus, the Pleiades and even some double stars, including Alberio which was easily split in the larger set of binoculars.

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M82 and M83 in Ursa Major were the brightest I’ve seen them in binoculars.  They popped into view when scanning the star fields, like two nebulous lanterns

Good views were also possible back at the hotel grounds, and the staff kindly accommodated my request to kill the driveway lights a few times.  The hotel also let us commandeer the library for our meals, allowing me to present some power point talks during dinner on Friday and Saturday evening.  My guests were very friendly and interesting company, with questions and conversation flowing easily.

Unfortunately, I neglected to take my camera into the field, so only took a few snaps from the hotel grounds at sundown. Look out for more Torridon dates in the future.

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The Torridon is situated under some of the darkest skies on earth.

Sky Watching in Turkey

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The waxing crescent Moon sits low on the western horizon over Bodrum, Turkey

On holiday in Turkey, and supposed to be taking a break, but couldn’t resist snapping the waxing crescent Moon over the clear but very light polluted skies above Bodrum.

What’s very apparent sky watching from this latitude, compared to Scotland, is the much steeper angle the ecliptic makes with the horizon, resulting is quicker sunsets and a much more pronounced ‘bowl’ orientation to the Moon near the horizon.

It’s also interesting to consider the religious significance of the Moon in Muslim countries like Turkey, where a lunar phase calendar is still in active use for religious ceremonies (marked by the crescent Moon and stars in many Muslim national flags).

Because 12 synodic months is 11 days shorter than the solar year, festivals like Ramadan end up drifting through the seasons.

This is in contrast to the West where the link with the Moon and the month was severed by the introduction of the Julian calendar around 40BC. Since then our civil and religious calendars have been entirely solar, with the Gregorian correction making our current calendar accurate to 1 day in every 3236 years.

Meteoric Start to New Star Stories

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The Milky Way glows overhead between thin tendrils of cloud.  Deneb and Vega shine brightly next to the bright and dark lanes of the Cygnus Rift.  By photographer Claire Rehr

The new Star Stories astronomy programme for the 2018/2019 season got off to a great start up at Abriachan Forest Trust last Friday, with plenty of clear breaks in skies for Milky Way observing and binocular stargazing. This was despite very unsettled weather predicted by the MET office as storm Callum blew in from the west.

This first event was in collaboration with the Highland Archaeology Festival, and pitched on a loose Neolithic stargazing theme which I had worked into a backup talk in the event of cloudy skies.  As it happened we had enough clear conditions to stargaze all evening and the talk was parked for another occasion.

Due to the healthy turnout we split the night into two streams, with one group joining Abriachan’s Clelland for Celtic tales around an open fire, while the other group joined me under darkness for a laser pointer and binocular tour of visible constellations.  We then swapped over at half time.

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Some broken clouds looking East with the Pleiades rising next to Perseus.  By photographer Claire Rehr.

Both stargazing groups saw plenty of open sky despite fast moving cloud, and we were able to field test the new hand held binoculars funded by our STFC grant.  The Milky Way and summer triangle were on fine display in the south with bright lanes of glowing star fields high overhead.  We also saw most of the northern circumpolar constellations, including Ursa Major, and discussed Polaris at some length before sighting the Pleiades in the East and the rich clusters within Perseus and Cassiopeia.

But the most dramatic event was gifted to the first group of stargazers, when a spectacular burning meteor soared overhead towards the north, briefly lighting up the whole sky.  A subsequent discussion on social media prompted another observer in Lairg – Chris Cogan – to post a picture of a very bright meteor he also saw streaking north and lighting up an entire hillside.

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The tail end of a bright meteor lighting up Lairg’s skies.  Photo by Chris Cogan.

This generated a lively discussion and some investigation into how far away two observers can be situated and still see the same bright meteor.  It turns out pretty far!

Due to the high altitude meteors burn up in the atmosphere, about 40 – 60 miles overhead, it’s very possible for two observers hundreds of miles apart to see the same meteor.  The only requirement is they lie along the same approximate vector as the burning space rock.  In this specific case, Abriachan and Lairg are both in a rough line travelling north.  The time recorded on Chris’s picture also checks out with our observing time at Abriachan.  So, all told, reasonably convincing evidence we witnessed the same fireball, seventy miles apart.

Overall feedback on the night has been great so far and I’m already looking forward to the Leonids Special in November, when we will be joined by guest speaker Dr Anthony Luke of UHI, talking about the chemistry of stars and meteors.

Clear skies!

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The Milky Way against the backdrop of the wooded hills at Abriachan.  Brilliant Altair and the constellation Aquila sit middle left.  By photographer Claire Rehr.

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Clelland spinning more starry tales around the open fire.  Photo courtesy Abriachan Forest Trust

The night sky photographs for this piece were kindly donated by Claire Rehr .  Please visit her Instagram account ‘rehr_images’ to see more of her stunning pictures.

 

 

Waning Gibbous Moon

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A waning gibbous Moon, photographed near Abriachan

I’m always snapping the waxing crescent Moon so here’s the waning gibbous Moon for a change. I took this on the trails above Abriachan around midnight on Friday, after a very wet and stormy evening in the camper van.

The word ‘wane’ is associated with weakness or sickness, and describes the diminishing aspect of the Moon after full. There’s a clear analogy of birth and death in the phases of the Moon that no doubt fascinated our forebears.

Astronomers often give the Moon a rough time due to its habit of spoiling dark skies, but it’s undoubtably one of the most mesmerising objects to look at. A complete world with the most incredible impact scars, recording the chaotic and violent formation of our solar system.

Observing the Moon each night is a dynamic experience as the terminator – the band where light meets dark – drifts back and forth across the lunar surface, revealing new features to contemplate.  In a telescope the terminator itself is a wonderful region to view, revealing kilometre long shadows from mountains and crater rims.  I like to imagine myself standing on the Moon in these regions, watching the Sun setting low on the lunar horizon.

Galaxy NGC 2841

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Galaxy NGC 2841. Imaged by Hubble nearly 50 million light years away in the constellation Ursa Major. This is an example of a spiral galaxy with no central bar, just a beautiful continuum of overlapping circular dust lanes.

It contains between 400 billion to 1 trillion stars, and like most galaxies outside our local group its receeding away from us, in this case at nearly 500 miles per second.