North Essex Astronomical Society

May 2013 Stargazing Evening

David W — Mon, 13 May 2013 19:24:46 +0000

Our next public stargazing evening takes place this Saturday 18th May, from 6pm until 9pm.

NEAS astronomers will be at the Great Notley Country Park in Braintree with a range of telescopes set up for you to look through.

As the sun now sets quite late, we may be able to some solar observing before turning out attention to the night sky and the first quarter Moon high in the southern sky.

As always our volunteers will try to answer any questions you might have, and give advice about how to start out with astronomy.

This is our last stargazing evening until the Autumn. Over the summer months, we will run midday solar observing sessions.

Everyone is welcome to come along and view through our telescopes. Attendance is free of charge. Please park in the site’s public car park (there may be a site car parking fee) which is just a short walk away and will remain open until 9pm. Details of how to find the site are on our Stargazing page here.

We will be set up behind the Discovery Centre building, so just following the walkway round to find us.

Please be aware that we are dependent on clear weather. If it is cloudy you obviously may not get to see anything! And if it’s really raining we will likely call off the event – so please use common sense before setting out. We will still have a couple of members on site in case you have any questions.

May Meeting – “Astronomical Spectroscopy”

David W — Tue, 07 May 2013 21:59:56 +0000

Our speaker this month is Jack Martin, who will be talking about “Astronomical Spectroscopy”.

Spectroscopy is a method used to analyse light by spreading it into its component colour wavelengths and studying the resulting pattern (as spectrum). Astronomical spectroscopy is the study of the spectrum of light from astronomical objects like stars, nebulae and galaxies. Use of spectroscopy has proven vital to our understanding of the universe and has enabled astronomers to infer many physical and chemical properties of objects.

Spectroscopy can be used to derive many properties of distant stars and galaxies, such as: chemical composition, temperature, mass, distance and relative motion (you’ve likely heard of the term “redshift”).

With modern cameras, a simple filter and computer software, spectroscopy can now be carried out fairly simply and inexpensively by amateur astronomers.

Jack Martin, author of the book “A Spectroscopic Atlas of Bright Stars”, will give an introduction to the concepts of spectroscopy and show examples of stellar spectra and what they mean.

The public meeting takes place at the Henry Dixon Hall, Rivenhall End on Wednesday 15th May at 7:30pm. For further information, see the Events page.

Sky Notes for May 2013 with James Abbott #stargazing

David W — Wed, 01 May 2013 20:19:32 +0000

May opens with Saturn near opposition, the point in its orbit where the Earth lies between the gas giant planet and the Sun. This means Saturn is also as its closest to us and is at its brightest. Even at this closest point for the year, Saturn is still over 800 million miles from Earth.

Seen with the unaided eye it appears as a yellowish bright object some 13 degrees to the left of Spica, the brightest star in Virgo. By mid-month Saturn is due South at 11.30pm BST and about 30 degrees in altitude. (Note: As a guide – If you hold your arm out, your fist will cover roughly 10 degrees of the sky.)

The famous rings of Saturn are now well presented to us and can be seen even with a good pair of binoculars. When the rings are “open” as they currently are, the planet’s brightness increases as the rings act like a mirror reflecting more of the Sun’s light back towards Earth. Unlike a real mirror though, the rings are actually made up of icy particles and ice boulders, orbiting the planet in a multitude of streams, all in a thin plane. As well as the rings there are over 60 Moons identified to date. These range from small bodies interacting with the ring system, up to Titan, which is slightly larger than Mercury, has a substantial atmosphere and would be classed as a planet if it was orbiting the Sun alone.

Saturn presents more Moons readily observable in typical amateur-sized telescopes than any other planet – five or perhaps six depending on aperture and conditions. Further information can be found in this article by Sky & Telescope.

Saturn: Image by Rachel Eaton

Full Moon is in the early hours of the 25th when the Moon will slink just 18 degrees above the Southern horizon after local midnight.

On May 12th there is one last chance this year to see a close pass of Jupiter by the Moon in the evening sky. At around 9.30pm BST the thin new crescent Moon will be just 4 degrees from Jupiter low down in the Western twilight.

The waxing Moon from mid-month coincides with the onset of summer twilight and so the best opportunity to observe in a dark sky will be the first half of the month, after which astronomical twilight will persist until the last week of July as the Sun remains at 18 degrees or less below the Northern horizon.

On 10th May it is just about dark by 11pm BST and the last of the winter constellations are bowing out in the North West. Last to slip towards the horizon is Gemini, the 2 bright twin stars almost parallel to the horizon. Gemini is a constellation that has a shape in the sky that resembles its name and when in the West, with a bit of imagination you can see two figures standing side by side. Turning around and looking to the North East the summer constellations are rising with Cygnus, The Swan, becoming prominent. Cygnus really does look like a swan in flight with its wings outstretched.

James Abbott is an astronomer, NEAS member and CfDS Regional Information Officer.

You can download a free map of the evening sky here:

April 2013 Stargazing Evening

David W — Thu, 18 Apr 2013 16:51:36 +0000

Our next public stargazing evening takes place this Saturday 20th April, from 6pm until 9pm.

NEAS astronomers will be at the Great Notley Country Park in Braintree with a range of telescopes set up for you to look through.

If the skies are clear, we’ll be hoping to do some solar observing to begin with – as the sun now sets quite late. As it gets darker, we’ll also be able to look at the Moon and maybe a couple of planets.

We’ll also try to answer any questions you might have, and give advice about how to start out with astronomy.

Everyone is welcome to come along and view through our telescopes. The night is free of charge. Please park in the site’s public car park (there may be a site car parking fee) which will remain open until 9pm. Details of how to find the site are on our Stargazing page here.

We will be set up behind the Discovery Centre building, so just following the walkway round to find us.

April Meeting – “Exploring the Solar System by Satellite” with Dr Stuart Eves

David W — Sun, 14 Apr 2013 15:59:26 +0000

This month for our public lecture, we welcome Dr Stuart Eves as our guest speaker, who will be talking about “Exploring the Solar System by Satellite”.

Stuart Eves is a principal engineer at Surrey Satellite Technology Ltd (SSTL), a company which designs and constructs small satellites. He spent over a decade with the Ministry Of Defence in several space-related positions before joining SSTL.

Amongst the spacecraft SSTL and Stuart has been involved with include the UK-DMC 2 disaster monitoring satellite and the award-winning high-resolution Earth imaging TopSat.

The public meeting takes place at the Henry Dixon Hall, Rivenhall End on Wednesday 17th April at 7:30pm. For further information, see the Events page.

ISS Over Essex (and the UK) – April 2013

David W — Sat, 06 Apr 2013 12:51:42 +0000

The International Space Station (ISS) will be passing over southern England during the evenings in April, and you can see it from Essex as it orbits the Earth above you.

Image: David Warrington

The ISS is a noticeably bright moving object and is fairly easy to spot, you just need to know when and where to look up!

You can find the viewing times of ISS flybys over Essex here, or you can click the “ISS Flyby Information” link in the right-hand menu.

It appears as a bright point object moving across the sky, usually taking 2 or 3 minutes to pass over. The space station isn’t emitting light – you are seeing it reflect sunlight from orbit as it passes over your location.

If you have a camera and tripod which can take a long exposure, you can also try taking a photograph.

Heavens Above is another website which allows you input your location details and find out about the ISS and other satellites passing over your skies. There are also various Android and Iphone apps that will alert you to ISS passes.

Sky Notes for April 2013 #stargazing

David W — Thu, 04 Apr 2013 21:05:04 +0000

In astronomical terms, Spring advances rapidly during April, but so far in 2013 meteorological Spring has been struggling to make any ground against a prolonged winter chill from the East. By the end of April daylight hours are essentially those of summer – with full daylight plus twilight lasting from 5am to 9pm BST. The Sun is still far enough below the Northern horizon during the night for there to be some hours of full darkness to view the stars.

Those hours of darkness may yet be an opportunity to see the Northern Lights from Essex. So far this solar cycle, the Sun has been relatively quiet, despite being near the maximum of its 11 year cycle. However, the time around the Spring Equinox is well known for producing active auroral displays. Moonlight and streetlights are major obstacles to seeing the aurora and so the best window of opportunity will be the first half of the month as the Moon is Full on the 25th – and of course a dark site. If the Earth is in the firing line of a major flare, with the many solar observatories on Earth and in space, not only can we see the flare event, we can predict the timing of the impact with the Earth’s magnetic field that can lead to bright aurora. A good source on this is Spaceweather.com

The waxing gibbous Moon will interfere with observations of the Lyrid meteors which are expected to peak on the night of the 21st/22nd but a few brighter meteors may still be seen in the late evening emanating from near Vega.

Jupiter finally starts to slip away into the evening twilight as April progresses, but before it is lost behind the Sun’s glare there is a fine conjunction on the evening of April 14th with the young crescent Moon passing just 2 degrees below the planet. The only other major planet readily observable is Saturn which by late April is about 20 degrees up in the South East in the late evening. The Full Moon passes 4 degrees – about 8 Moon widths – below Saturn on the evening of the 25th.

Despite the worst efforts of the weather, Comet C/2011 L4 (Pan-STARRS) was seen from Essex, from the evening of March 12th onwards, low in the Western twilight. In binoculars it showed a bright coma of mag +1 and a slightly curving tail of up to 1 degree in length.

This image, taken on the 13th March is similar to the visual appearance through binoculars at the time:

Image by David Warrington

The comet is now fading as it moves away from both the Sun and the Earth but is still worth chasing in binoculars or a wide field telescope as it is displaying a very broad dust tail. In the first week of April it glides past the Great Andromeda Galaxy M31 before crossing into Cassiopeia on the 9th. On the 20th – 22nd it passes less then 2 degrees to the East (left) of beta Cas, the top right star in the W of Cassiopeia. The comet becomes circumpolar in April and so can potentially be followed all night – and at last can be seen against a dark sky, albeit still fairly low in the North.

James Abbott is an astronomer, NEAS member and CfDS Regional Information Officer.

You can download a free map of the evening sky here:

March Meeting – Nik Szymanek: “Beginners Guide to Astrophotography”

David W — Fri, 15 Mar 2013 16:27:08 +0000

Nik is widely acknowledged around the world for his deep sky astrophotography, as well as his image processing abilities, and his pictures are frequently published in the leading astronomy magazines and publications.

Although carrying out most of his imaging from his home in Essex, he also travels to more remote locations in order to take advantage of some of the best observing sites – producing some of the best CCD images and widefield night sky photographs you will see.

Nik will give us an introduction to all the modern forms of astro imaging, how to get started and what techniques to try out.

And, almost as importantly, he’ll showcase a selection of his amazing photography!

The public meeting takes place at the Henry Dixon Hall, Rivenhall End on Wednesday 20th March at 7:30pm. For further information, see the Events page.

March 2013 Stargazing Night

David W — Tue, 12 Mar 2013 13:22:33 +0000

UPDATE: Tonight’s event has now been cancelled, not only due to the poor weather but also due to the current waterlogged nature of the site. Sorry – we’ll try again next month!

On the evening of Saturday 16th March, NEAS astronomers will be at the Great Notley Country Park in Braintree for a night of astronomy from 6pm to 9pm.

If the skies are clear, there’ll be a range of telescopes set up through which you’ll be able to observe the night sky.

The planet Jupiter will be high in the sky, along with a crescent Moon, and the constellations of Taurus, Orion and Canis Major.

We will also be trying to find Comet Pan-STARRS, which should be low in the west just after sunset – but we can’t guarantee it!

If you own a telescope and you need some assistance setting it up, and we’ll also try to answer any astronomy questions you might have.

Everyone is welcome to come along and view through our telescopes. The night is free of charge. Please park in the site’s public carp park (there may be a site car parking fee) which will remain open until 9pm. Details of how to find the site are on our Stargazing page here.

We will be set up behind the Discovery Centre building, so just following the walkway round to find us.

Please be aware that we are dependent on clear weather. If it is cloudy you obviously may not get to see anything! And if it’s really raining/snowing down we will likely call off the event – so please use common sense before setting out. We will still have a couple of members on site in case you have any questions.

Comet C/2011 L4 PanSTARRS

David W — Mon, 11 Mar 2013 19:39:57 +0000

Image: Terry Lovejoy

As long as you have clear skies and a good view of the western horizon, this week could be a good opportunity to try to find and observe Comet PanSTARRS.

Discovered in 2011 by the PanSTARRS telescope in Hawaii, the comet has since increased in brightness as it’s made its way through the solar system toward the Sun and has also developed a noticable tail.

To be in with a chance, you’ll need to observe the western sky approximately 30 minutes after the sun has set.

However, you should bear in mind that it perhaps won’t be the easiest thing in the sky to find.

Low on the western horizon and so soon after sunset, it will be difficult to spot. Anyone who has ever tried to observe the planet Mercury close to sunset will know just how tricky it can be.

Also comets are quite tenuous objects and not just points of light in the sky. So even a “bright” comet will not appear quite the same as an equal magnitude planet or star.

Image: Spaceweather.com

To make matter worse, some of the sky chart graphics currently being used can be somewhat misleading to those with less experience. It’s can be hard to judge just how high or low up in the sky this comet will be from your location.

This is probably a more realistic view of the comet:

But if it is clear and you do have a clear western horizon, give it a go. All you should need to do is grab a pair of binoculars. If you’re lucky you may see get to see the comet. If you’ve got a camera, you could even try photographing that region of the sky.