The SPA have held an autumn weekend course about practical astronomy at Preston Montford near Shewsbury almost every year since 1977, and the 2017 event, held in November, was as popular as ever. Some 40 participants gathered on the Friday evening to hear welcoming talks from Prof Ian Morison, Robin Scagell and Pete Williamson, making his first visit to Preston Montford. Read more
We are putting the finishing touches to our wonderful new website, which is due to go live on 20 January 2018. Read more
News is coming in that a bright fireball was seen across much of the UK at about 5.35 pm on 31 December. Read more
The Leonid meteors over the weekend have produced some spectacular fireballs, though as expected rates were fairly low and there was no ‘meteor storm’. Read more
A Leonid storm in 2017? Simple answer: No. Longer answer: probably not. Read more
This is a particularly good time to look for Iris, as at the end of October it reaches its maximum possible brightness of 6.9. That is below naked-eye visibility, but easily reachable with even small binoculars. But you have to know exactly where to look.
Fortunately it is passing through the constellation of Aries, which is currently well placed looking quite high in the sky in the south-east during the late evening as seen from the UK. While not a bright constellation, itâ€™s easily found by anyone with a basic knowledge of the sky. Its three brightest stars make an easily recognisable group. Use the map below first to find Aries itself. With binoculars, first identify the three main stars of Aries, then use our map to â€˜star-hopâ€™ through the patterns of fainter stars to Iris.
Although Iris is about 130 million miles away, it moves noticeably against the starry background from night to night, so if you want to pick it out you need to know its position when you are looking. Bear in mind that the tick marks on the map are for midnight at the start of each day, so if you are observing before midnight, the asteroid will be close to the next dayâ€™s mark.
With exposures longer than a few seconds, and telephoto lens settings, the stars will start to trail after more than about four secondsâ€™ exposure as the sky moves (or, more accurately, the Earth turns). So to keep the images as points of light, use a short exposure time and a high ISO setting.
The photograph at top was made using a 125 mm lens setting on a Canon 70D camera, with a 75-second exposure. The camera was driven to follow the stars. The image is cropped.
Nebula IC 63 in Cassiopeia. The bright star is Gamma Cassiopeiae
The sky is full of mysteries, but we’ve picked out a few that look particularly spooky for Halloween. All the pictures were taken by Nick Hart from his observatory in light-polluted Newport, South Wales.
A ghostly apparition in Cepheus â€“ the nebula IC 1396
Among the stars at centre of NGC 1977 in Orion is a figure covered with a sheet to scare us
A witches’ cauldron? No, the nebula IC 5070 in Cygnus.
All photos copyright Nick Hart
An Orionid meteor in Gemini photographed on the early morning of 22 October by Paul Sutherland from Walmer, Kent
After the scare the other week in the media about a non-existent meteor shower, now for the real October meteors â€“ the Orionids.
These appear in good numbers between 20 and 23 October, and official rates are given as 20â€“25 an hour. But that’s the number that could be seen under ideal conditions, which never apply in the UK, so actual rates are likely to be somewhat lower. In practice you might see one every ten minutes or so on average, if you are a good, dark location and can see all the sky with clear conditions. And that applies in the early morning hours, so be patient!
These meteors appear to come from the direction of Orion, which rises in the east at about 10 pm BST, so any meteors you see before that time won’t be Orionids. Once the radiant (the source point) rises, numbers will increase throughout the early hours. This year, the Moon is just after new, so won’t interfere with observations, and even better, the peak occurs at a weekend. The weather is a bit unsettled in the UK, but there’s still the chance of good clear skies.
Orionid meteors are typically swift-moving, with long and persistent trains. While there is no particular direction where they will appear, it’s best to avoid looking directly at or near Orion itself, as the meteors will appear foreshortened in that direction and won’t be as easy to spot. The diagram on the right shows the position of the radiant and how it moves against the starry background during the shower appearance.
Get more information on the Orionids and how to observe them at the SPA Meteor Section site. If you want to contribute, please count the numbers of Orionid and other meteors that you see in an exact period, and send them to the Meteor Section director.
Meteors and comets
The Orionid meteors arive from dust left by Halley’s Comet. Does the appearance of these meteors mean that we might see Halley’s Comet as well? Sadly, no. What happens is that the dust from the comet has spread all along the comet’s orbit around the Solar System. Halley’s Comet is now almost as far away from Earth as it can get, beyond the orbit of Neptune. It has also spread over a wider area than the comet’s orbit itself, which is why we see these particles coming through our atmosphere even though Halley’s Comet itself can’t come very close to the Earth.
Imagine the comet to be an aerobatic plane doing loops and giving out a smoke trail. You could see the whole loop as a large trail in the sky, wherever the plane happens to be, and spreading out all the time.
Every October, Earth passes through the edge of this trail, and ploughs through the particles, which dash into our atmosphere and burn up, creating the brief flash of light we call a meteor or shooting star.
Hurricane Ophelia has stirred up a lot of dust from the Sahara Desert, and ash-particles from wild fires in Spain and Portugal, and lifted them high into the atmosphere. Yesterday, there were wide-spread reports of the sky turning orange from many parts of the UK. By mid-afternoon the Sun showed up distinctly orange-red even though it was not near the horizon. SPA member, Michael Fullerton captured the image below from Norfolk.
Orange Sun seen from Buckinghamshire this lunchtime. Photo: Robin Scagell
People across Britain have seen the Sun turn bright orange or even red. The daylight is also a strongly orange colour. We have even heard of one person fearing that the Apocalypse was upon us!
It is also reminiscent of the cover of astronomer Fred Hoyle’s 1957 novel The Black Cloud. In that case, the darkening of the Sun was due to an alien life-form resident within an interstellar cloud that took up residence around the Sun, causing widespread panic and destruction.
But it’s actually due to the strong southerly winds caused by storm Ophelia. These are bringing air laden with dust from Portuguese forest fires over the whole UK.
As soon as the wind changes direction, the Sun will return to its normal colour.
Photographing the colour
Some people have said that their photos of the strange lighting effects don’t show the colours they can see. This is because most cameras and phones now use ‘auto white balance’ which takes into account any changes in the overall colour of the light. So they take equally good pictures indoors as outdoors, even though the lighting is completely different. However, this isn’t what you want when the scene contains a predominant lighting colour, such as today.
The solution is to use a Daylight colour setting if your camera has manual settings. It’s also possible that using the flash will set the camera to its daylight colour setting even when it’s on Auto.