JULY NEWSLETTER 2007
INDEX: MEETINGS, OTHER NEWS, CONTACTS
COMMITTEE
MEETING
Members
of the Society's Committee are respectfully reminded that the next Committee
Meeting is to be held at the Abergaveny Arms in Frant on Monday the 9th of July
beginning at 1930.
JUNE MEETING
As
the June meeting was held on the shortest night of the year the Society held an
open evening when members were invited to bring telescopes, photographs, books
and other aids to astronomy, giving members the chance to talk about their
experiences and projects in an informal way.
It turned out to be a very full and varied evening.
There
were six telescopes altogether including:
The
Ian Reeves Konus 120 mm refracting telescope
A
5-inch Schmidt reflecting computer controlled telescope
A
66 mm and an 80 mm refracting telescope both with Williams Optics
An
11-inch Celestron Schmidt-Cassegrain Catadoioptric telescope with German
Equatorial driven mount
A
40 mm hydrogen-alpha Coronado PST (Personal Solar Telescope).
It
may be worth mentioning at this point that the Ian Reeves telescope belongs to
the Society and is available for any member to borrow.
A
visitor to the meeting said that he was visiting the town and had seen our
meeting announced on the Wadhurst Town notice board.
He was from Hertfordshire but had with him a series of photographs
showing how he had constructed an 18-inch reflecting telescope on a specially
made fork mount. It had taken him a
total of fourteen years to complete but was a very impressive instrument mounted
in a specially constructed observatory.
Astrophotography
The
highlight of the evening was Phil Berry's illustrated talk about
astrophotography. He began by saying that after some of our recent excellent
talks, some members felt that they needed a Faulkes telescope to enter the field
of astrophotography but Phil explained that this was quite wrong and anyone with
little equipment could produce very satisfying results.
An
interesting observation is that atmospheric turbulence can be more degrading on
telescopes greater than 8-inches!
One
of the biggest advantages amateurs have is time. They can afford to take many
short exposures and with available computer software, - often free, can
reassemble many faint images in quite remarkable detail, even though very small
CCD cameras are used.
For
Phil's presentation he said he had borrowed some images from Ian King, another
of our members, and began by showing us NGC 4631, an edge-on spiral galaxy taken
with an 8-inch reflector. The
galaxy is in the constellation of Canes Venatici and has an apparent magnitude
of +9.3. The image also revealed a
gaseous cloud, which had a temperature of well over a million degrees Celsius.
NGC
6888 is a Super Nova remnant, 20 minutes across.
The shape clearly showed the advance of the material thrown off during a
gigantic explosion that took place about 400,000 years ago.
Phil
had with him his Coronado 40 mm Personal Solar Telescope (PST) and explained
that he had been able to make some remarkable observations of the Sun in
hydrogen alpha light. He used an
image that Mathias Bopp in Germany had achieved using a web cam on an identical
telescope to illustrate what could be achieved with affordable equipment.
Images
of more familiar sights were illustrated by an image Phil had obtained with his
80 mm reflector of the Pleiades, M45. The cluster is 110 minutes wide with a
magnitude of +1.2. Seen with the
naked eye, usually only the "Seven Sisters" can be seen but there are
many hundreds of stars within the cluster.
In Phil's image the dust and gas around the cluster showed up clearly as
a sweeping blur of the brighter stars.
Phil
talked of one effect he had discovered when using his 5-inch Schmidt telescope,
which had exhibited itself as very small corrections both in the RA direction
and the Dec direction causing the corrections during a timed exposure to zig-zag.
He cured this effect by setting the telescope's wedge to the latitude of
the telescope so that only tracking in one direction was achieved.
We
were shown an incredible image of M31, the Andromeda Galaxy, taken by Ian King
for which he had been awarded the Astronomy Now magazine award of the year a few
years ago (massive £25!)
To
show what was possible we were able to compare an image of M51, a spiral galaxy
close to Alkaid, the last bright star in the handle of the Plough taken by the
Hubble Space Telescope, and then we were shown the same galaxy taken using an
8-inch reflector. With use of
computer software to reduce the contrast, the image taken with the 8-inch
appeared clearest which showed what the amateur with very modest equipment could
achieve.
Finally,
Phil showed a picture of himself next to the Hubble Space Telescope!
Then he explained that two Hubbles had been built in case one failed and
now the second one is exhibited at the Smithsonian Space Museum in Washington.
Phil was absolutely dwarfed by the 13.2 metre high space satellite!
In
conclusion, Phil said we have the time to produce great images even with small
resources.
Digital
SLR Cameras and Astronomy
At
the meeting Bob Seaney asked if any one had had any results using digital SLR
cameras on the night sky. He has
a camera with a 6 x zoom and was interested in hearing other people's experiences.
JULY MEETING
Wednesday
18th July 2007 George
Satterthwaite will be giving a talk about "George Airy and His Contribution
to Positional Astronomy".
FUTURE MEETINGS & EVENTS
Monday
9th July 2007 Meeting of the
Committee 1930 at the Abergaveny Arms, Frant
August
There is no meeting of the Society in August, but once again, we have
been kindly invited to an Astro Barbecue hosted by Michael Harte and his wife at
Greenman Farm on Saturday 25th August 2007.
Greenman
Farm, Wadhurst, is on the south side of the B2099 immediately to the west of the
railway over-bridge. All Society
members are invited and Michael suggests that members aim to arrive at about
7.00 pm.
You
will only need to bring your own food and drink, as everything else will be
provided.
In
previous years this has been a very enjoyable event and gives members a chance
to meet others in a relaxed and enjoyable atmosphere.
Members
are invited to bring telescopes, binoculars and anything else of interest, but
mainly themselves.
Adding
a note of caution. It is late
August and can be a bit cold as the evening progresses, so it might be worth
bringing some warm clothing.
Saturday
22nd September 2007 A visit to
see the largest private collection of clocks in the UK at Belmont House near
Faversham in Kent. Details later in
the Newsletter.
Wednesday
17th October 2007 Keith
Brackenborough will be giving a talk with the intriguing title "The
Calendar - A 5,000 year struggle to
Align the Clock to the Heavens".
Wednesday
21st November 2007 John
Vale-Taylor is presenting "The Tim Bance Interview".
Tim is a long-standing member of the Society and has a wealth of
practical experience in the field of amateur astronomy.
VISIT
TO BELMONT HOUSE
On
Saturday the 22nd of September, The Society is visiting one of the finest
collections of clocks in Britain. Members
going have already given their names to Phil Berry but anyone else wishing to go
should contact Phil by the July meeting so that he has the number of members
going. His telephone number is in the Contacts list at the end of
the Newsletter.
We
will need to find our own way there in our own transport.
The house is in its own grounds and directions to get there are as
follows:
From
Ashford / M20, exit junction 9
Take
A251, heading North in the direction of Faversham. Pass through the village of Boughton Aluph (2 miles),
straight across the Challock roundabout (4 miles) and continue North until
Badlesmere. Turn left and follow the brown Tourist signs for Belmont; a further
1.5 miles.
From
Faversham / M2 exit junction 6
TELESCOPE
FOR SALE
Bob
Seaney is selling an eight-inch LX 10 reflecting telescope.
This is an ideal telescope for the more serious amateur and would provide
the opportunity to get involved in more fundamental observing.
The
telescope, which is in excellent condition, has its own travelling box.
It has an equatorial battery driven mount with hand controls.
The instrument takes standard one-and-a-quarter-inch eyepieces and comes
with a 40 mm eyepiece.
The
telescope has a heavy metal tripod for good stability.
Bob is asking £450, which is very reasonable and he can be contacted on telephone number 01580 752350.
REQUEST
FOR A SPEAKER FROM THE NATIONAL TRUST
Our
Chairman has received a request from the National Trust at Bateman's asking for
someone to give them a talk about astronomy.
The talk would need to be about 60 to 90 minutes and would be scheduled
for sometime next year.
The
idea came from one of the gardeners whilst gazing up at their unpolluted night
sky.
Further
information may be obtained from John Vale-Taylor.
SAGAS
SAGAS,
the Southern Area Group of Astronomical Societies, is holding their Summer Event
on Saturday the 14th of July and members of our Society are invited to attend.
The meeting is being hosted by the Vectis Astronomical Society on the
Isle of Wight.
The
event will take place at the Isle of Wight Observatory, Watery Lane, Newchurch
Near Sandown, I.O.W. Grid ref: SZ554843.
The cost is £5, which covers all costs, refreshments and a light lunch.
The
provisional timetable is:
1100
Delegates arrive at observatory
1300
Lunch
1430
Meeting
1730
approximately, - end
Speakers
will be:
John
Mason (Chichester Planetarium) "Mars Exploration Update"
Ninian
Boyle (Venturescope)
- "Solarscopes"
Peter
Burgess (Vectis AS)
- "Beyond the Eyepiece"
Graham
Bryant (Hampshire AG/CfDS) - "Measuring
Sky Quality by Light Meter"
The
Vectis Astronomical Society would need names a week before the event to enable
them to organise appropriate catering.
Please
phone Richard Flux on his home number 01983 883063, or email the Vectis
Secretary - John Smith on Johnwsmith.iow@tiscali.co.uk
Further
information can be obtained from the Vectis AS website on:
JULY NIGHT SKY
Planets
Mercury
becomes a morning object in July and may be seen around the 24th/25th/26th. It
will be difficult to find in twilight as it rises only around an hour before the
sun.
Venus
at magnitude -4.0 is moving towards inferior conjunction and by the end of the
month sets less than an hour after the sun. During July its phase becomes a
thinner crescent whilst its apparent diameter increases.
Mars
at magnitude 0.5 lies on the borders between Aries (the ram) and Taurus (the
bull). It is still a morning object but by the end of the month it rises a
little after midnight (BST) with its apparent diameter steadily increasing.
Jupiter
Still lies in the constellation of Ophiuchus (the serpent bearer) at magnitude
-2.5. Sadly it is never more than 17º above the horizon and by mid July sets
around 02.00 BST. Binoculars or a very modest telescope will easily show the
four brightest moons - Io, Europa Ganymede and Callisto.
Saturn in Leo (the lion) at magnitude 0.6 is difficult to observe and by the end of July will be lost in the glare of the sun. On July 1st Saturn and Venus are less than a degree apart in the sky.
Lunar
Occultations
This is a lean month for lunar occultations with only two that fall within our normal criteria of being brighter than magnitude 7 and occurring before midnight (BST). As a result I've included a few that are slightly fainter or occur a little later. Times are all BST.
| Date | Time | Star (SAO Catalogue) | Constellation | Magnitude | Phase |
| Fri 20th July | 22.25 | SAO 138905 | Virgo | 7.3 | DD |
| Sun 22nd July | 22.16 | SAO 158384 | Virgo | 7.7 | DD |
| Tue 24th July | 22.30 | SAO 183794 | Libra | 7.0 | DD |
| Thur 26th July | 00.49 | SAO 184602 | Ophiucus | 6.0 | DD |
| Fri 27th July | 22.06 | SA0 187048 | Sagittarius | 6.8 | DD |
Meteors
Possibly
the most watched meteor shower of the year is the Perseids which begin on July
23rd. Although there will be few meteors about so early in the shower, it is
still worth keeping a watch if you have the time. I usually try to observe on
every available clear night up until August 20th, which is generally considered
to be the end, and in the past have been rewarded with a spectacular exploding
Perseid.
In
order to be comfortable it is best to lie on something like a sun lounger (foot
end pointing a little east of north) with the head end slightly raised so that
you can see as much sky as possible. Only a few meteors are seen very close to
the radiant so a wide vista is important. I can remember watching the shower
from Cornwall in 1999 (after the ill-fated eclipse) and some of the meteors
almost reached the southern horizon behind us.
However,
my own favourite way of observing the Perseids is to lie on the gently sloping
roof of my bungalow on a platform that I made especially for the purpose. It
consists of a long board that fixes around the chimney with a footrest to stop
me sliding down the roof.
ISS
Unfortunately,
there are no passes of the ISS in July that occur before midnight. For more
details log on to the web-site: www.heavens-above.com
NASA
SPACE PLACE
Chew
on This
By
Diane K. Fisher
The
Mars robotic rovers, Spirit and Opportunity, are equipped with RATs, or Rock
Abrasion Tools. Their purpose is to
abrade the surface patina off the Mars rocks so that the alpha x-ray
spectrometer can analyze the minerals inside the rocks, rather than just on the
surface.
But
future robotic missions to Mars will be asked to go even further below the
surface. Scrapers and corers will
gather rock samples of substantial size, that, in order to be analyzed by a
spectrometer, will need to be crushed into a fine powder.
Crushing
rocks on Mars? Now there's a
problem that brings to mind a multitude of
possible approaches: Whack
them with a large hammer? Squeeze
them until they explode? How about
just chewing them up? It was with
this latter metaphor that the planetary instrument engineers struck pay dirt-so
to speak.
Thanks
to NASA's Planetary Instrument Definition and Development Program, a small group
of NASA engineers came up with the Mars Rock Crusher.
Only six inches tall, it can chew the hardest rocks into a powder.
The
Mars Rock Crusher has two metal plates that work sort of like our jaws. One
plate stays still, while the other plate moves. Rocks are dropped into the jaw
between the two plates. As one
plate moves in and out (like a lower jaw), rocks are crushed between the two
plates. The jaw opening is larger toward the top and smaller towards the bottom.
So when larger rocks are crushed near the top, the pieces fall down into the
narrower part of the jaw, where they are crushed again. This process repeats
until the rock particles are small enough to fall through a slit where the two
plates are closest.
Engineers
have tested the Mars Rock Crusher with Earth rocks similar to those expected to
be found on Mars. One kind of rock is hematite. The rusted iron in hematite and
other rocks help give Mars its nickname "The Red Planet." Another kind
of rock is magnetite, so-called because it is magnetic. Rocks made by volcanoes
are called basalts. Some of the volcanoes on Mars may have produced basalts with
a lot of a mineral called olivine. We call those olivine basalts, and the Rock
Crusher chews them up nicely too.
Visit:
Chairman John Vale-Taylor pjvalet@tiscali.co.uk
Phil Berry 01892 783544 phil.berry@tiscali.co.uk
Treasurer
Mike Wyles 01892 542863
Publicity &
Website Michael Harte 01892 783292
Newsletter Editor Geoff Rathbone
01959 524727
Any material for inclusion in the August Newsletter should be with the Editor by July 28th 2007