Graham Hodson outlines details of the MAS new website, and plans for a new Astronomy forum; Nigel Longshaw takes us to the moon to examine enigmatic craterlets; the MAS mirror making team give an account of their trials and tribulations and outline 'the story so far...'; Tony Cross provides some useful tips for astrophotography under those summer skies and an amusing story about the Bevis atlas; Guy Duckworth identifies some interesting targets for Spring sky observers and tells us how we can tackle the dreaded 'dew' problem in observational astronomy; and gives a Presidential view on the Renold Lectures. We also have an account of observing and photographing Egyptian night skies and details of Comet C/2002 C1 Ikeya-Zhang from Rob Philburn. There's even a crossword and an example of astro-humour to keep you amused and occupied during those not infrequent occasions when the infamous Mancunian cloud pays a visit, plus the results of the Annual Photographic Competition 2001.

Rob Philburn
Editor.

CURRENT
NOTES

Spring 2002

Graham Hodson

About 9 months ago, the web pages for the 'MAS Members Page' and associated images were transferred from the web space of Mike Oates to my web space.

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FOUNDATION WORKS IN ASTRONOMY - Literally

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17TH JAN 2002. Dr Andy Hollis. presents his lecture THE OUTER PLANETS. Supported by all the latest electronic devices (digital projector etc.) everything was set up and ready for action. Well nearly. No support could be found for the projector: tables were too short or too far away from the screen; books were brought but to thin. But in the audience, en route to the library in Cambridge, was the ATLAS CELESTE by JOHN BEVIS (1695-1771). It was suggested that it should be brought down and given a try. Low and behold it was perfect. The evening went well, the speaker was thanked, and all went home .
Never before had a present day speaker dreamed that he would be helped out by the most expensive support in the business - to the tune of an estimated £40,000.

WELL DONE JOHN BEVIS, STILL MAKING AN IMPACT ON THE ASTRONOMICAL WORLD !

TONY.W.CROSS.

I have recently become aware of a number of features of Plato itself and its surroundings which has given me renewed interest in the formation.

Firstly everyone I am sure is familiar with the appearance of the interior of Plato , consisting as it does of a dark flooded floor peppered with tiny craters of varying sizes. I have never had much success observing these craterlets even though there are approximately nineteen , of varying sizes, marked in The Times Atlas of the Moon. I have always assumed that the best time to observe these tiny features is around the eight to nine day old Moon , when the terminator crosses Plato . However according to Brian Tung in "letters" to 'Sky and Telescope' (September 2001), he found the main craters easily visible around full Moon . It certainly seems worth observing Plato around full Moon to try and confirm if this is the best time to capture these illusive features , if nothing else at least it means your 'scope will not be idle when the Moon is full .

The second feature of interest in the area of Plato lies immediately South of the crater on the Mare Imbrium and has attracted some debate recently in the B.A.A. Lunar Section Circulars and quarterly publication The New Moon. This concerns a feature named Newton by Schroter in the 1790's . It appears that this region gives the impression of a "buried" crater under favourable illumination , the evidence for such a feature was enough to convince Schroter that this was worthy of a separate name.
In their later map and atlas Beer and Madler sought fit to transfer the name Newton to the now familiar feature towards the Southern pole , and Schroter's "Ancient Newton" disappeared into obscurity .
The evidence for "Ancient Newton" can be observed about one day after first quarter Moon and is made up of a collection of different features which appear to be "related". Firstly a wrinkle ridge runs from the Eastern tip of Plato in a South Western curve and appears to join the isolated mountain peak Pico. The effect of an "enclosure" is completed by the Tenerife mountains as they sweep Northwards towards the Western tip of Plato. The alignment of these features creates the illusion of a much degraded crater approximately the same size as Plato itself . There is still some debate as to whether these features represent separate geological formations, or whether they were once part of a large crater which has become flooded by Mare Lavas . Have a look yourself around first quarter Moon , and come to your own conclusions.

Lastly an interesting observation was made by a member of the S.P.A. recently using only a forty five millimetre diameter gun sight telescope giving a magnification of times five. At just after full Moon he observed "two Plato's" , or more precisely two dark spots in the area of Plato. One was of course Plato itself , the other was an area of darker Mare floor bounded by the Tenerife mountains and the Straight Range. The full Moon photograph in Hatfield's Photographic Lunar Atlas shows something of this effect . On plates 6a and 6b in the same book there is evidence of a "darker" region in this area which I am sure is enhanced at low powers by the mountain ranges at its boundaries. I am sure this effect would be lost to larger higher powered instruments and should be an ideal target for binoculars.

I have yet to attempt any of the above mentioned observations , but I will certainly do so when conditions permit , it's nice to know that even such a well known region can still hold secrets for the willing observer.

I have included a chart of the area, noting the location of the features described in this article.

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Tony Cross

V E R N A L   E Q U I N O X

SO WHAT SHOULD WE DO? Here is a short checklist of things to remember for both beginner and experienced astrophotographers:

(1) Give camera good overall use BLOWER BRUSH to get bits of dust off.

(2) Check LENS for any finger marks and make sure that the F.STOPS are closing and opening.

(3) If the camera operates on BATTERIES, give the CONTACTS a good clean.

(4) Make sure you look at the INSIDE of the CAMERA BODY, especially the TAKE UP SPOOL; this is always a trouble spot. When you wind on a new film, as the TAKE UP SPOOL grips the LEADER, small BITS of FILM can shave off. If one of these gets caught you will have a ruined film as well as an expensive repair bill!

(5) As astronomers, we always use a CABLE RELEASE. Then why do we always forget them, or find that they do not operate when we come to use them? To be on the safe side always have a spare CABLE RELEASE in your CAMERA BAG.

(6) For good ASTRO SHOTS you need a good STEADY TRIPOD, so check out that your TRIPOD is in good condition. Why not put some REFLECTIVE TAPE round the bottom of the LEGS (I am sure you must have tripped over them at sometime).

(7) Whatever DRIVE SYSTEM you are using , now is the time to give it the works. Check out the POWER SUPPLY, IF IT IS OF THE MODERN DAY TYPE. If its of the wind up type ,WIND it up and leave for a few days and check if the SHAFT is rotating.

(8) When it comes to FILM, you know what you want to achieve so the choice is yours, but remember when you purchase the FILM keep it COOL; the bottom of the FRIDGE will be quite safe as long as you SEAL THE film up in a good WATER TIGHT WRAPPING.

(9) You have to get the CAMERA and DRIVE SYSTEM plus TRIPOD to the location for your nights astro session, So put everything in one bag.

(10) YOU ARRIVE AT YOUR SITE , START TO UNPACK: CAMERA , DRIVE MOUNT, TRIPOD , CABLE RELEASE, LENS, OH "NRFVIUHTGHCI RGV UV VUVVBXXXXXX IT!", OR WORDS TO THAT EFFECT, YES YOU HAVE FORGOT TO PACK THE FILM

PLEASE DO MAKE A CHECK LIST , OF ALL THE THINGS THAT YOU NEED.
PUT IT ON A CARD AND HAVE IT WITH YOU AND WHEN YOU START TO PACK. CHECK OFF ALL THAT YOU PUT IN YOUR BAG. THIS IS THE ONLY WAY YOU CAN BE SURE THAT YOU WILL FORGET NOTHING.

I HOPE THAT YOU WILL FIND THE ABOVE INFORMATION HELPFUL, AND WISH YOU ALL CLEAR NIGHTS AHEAD

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Nights over Egypt: A note on photographing the night sky in the land of the Pharaohs

The night sky
Although crystal clear and cloudless during the daytime, the sky was surprisingly 'murky' at night. The central bulge of the milky way could be made out around the 'spout' of the Sagittarius 'teapot', and traced up to and beyond Cygnus. This was however not the glittering spectacle that I had expected, considering our considerable distance away from the nearest large city. Another society member (Colin Henshaw) with substantial experience of this part of the world had in the past spoken of similar seeing conditions in Saudi Arabia, where the sky was effectively permanently polluted with dust and sand due to the extreme heat and absence of rain. These features seem to extend to the Egyptian side of the Red Sea.

The Deep Sky in the Coming Months (Spring 2002)

Many of our members live under light polluted skies and may not always be able to escape to the country for an observing session, a necessary prerequisite for proper views of the numerous galaxies within the Virgo supercluster during spring. However, planetary nebulae afford a good alternative to galaxies; their centres are often bright and they stand magnification well, even amidst light pollution. Suitable targets would be NGC 2392, the Clown Face (Eskimo) nebula near Delta Geminorum; NGC 3242, the Ghost of Jupiter below Mu Hydrae; NGC 40 in Cepheus: M76, the Cork nebula in Perseus; NGC 1514 in Taurus (which gave planetary nebuale their name, this one resembling the disc of Uranus); NGC 2438 amidst the open cluster M46 in Puppis; NGC 4361 in the middle of Corvus; IC 2149 near Beta Aurigae and NGC 6543, the Cat's Eye nebula near Zeta Draconis.
If binocular observers can only locate the brighter examples, they may find solace in observing the numerous coloured K, M & C type stars in Leo and Hydra.

Guy Duckworth

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Astronomy Crossword

Here's an Astronomical crossword puzzle that everybody should be able to have a fair crack at. The answers will be posted on the MAS noticeboard and in the next 'Current Notes'.

Have a go at some more Astronomy puzzles at:
http://users.efni.com/~brentt/astropuzzles/menu_astropuzzles.htm

RP

Reprinted here with the permission of the author

Across
8 Falling star (6)
9 Crab Nebula caused by a ____ I supernova (4)
10 Most things in space are travelling at _________ speeds (10)
11 The red planet (4)
12 Sky measured in degrees, ___ minutes and ___ seconds (3)
14 Used in balloons (6)
15 ____ sky (4)
17 Abbr of second element (2)
18 Star _______ (7)
21 Aircraft sometimes used in astronomy (3)
22 Cast during an eclipse (6)
24 Energized molecules high in the atmosphere (4)
25 Receives radio signals from outer space (4)
28 Time left on a journey, abbr (3)
30 Mars ______; group of people (6) 31 A white dwarf or neutron star is extremely this (7)

Down
1 Huge patch of lit dust in space (6)
2 Observing tool (9)
3 Asteroid recently visited by spacecraft (4)
4 After a rainfall, hopefully (7)
5 Not even light can escape these, pl.(10)
6 A molecule is made of these (4)
7 Controls the amount of light going into telescope (8)
13 If you lived on another world you are an? (10)
16 What you look through on a telescope (8)
19 Ball of nuclear fusion (4)
20 Permanent massive greenhouse effect (5)
23 The better these are, the better the view, pl.(6)
26 Comet ____/Bopp (4)
27 Just a second away for light to travel (4)
29 Military ___ satellites (3)

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MAS Annual Photo Competition

In December of last year, the society held its regular Astrophotography competition. As usual, the entrants provided a wide variety of high quality images, ranging from planetary nebulae to shadow transits of Ganymede. An audience vote resulted in the following 3 winning images:

1st. Occultation of Saturn by Rob Philburn
2nd. Aurora Borialis by Mark Adamson
3rd. Lunar Halo by Graham Hodson

Congratulations to all entrants.
RP

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M.A.S. Online Forum

During the summer of 2001, a group of members who were discussing the merits of the MAS website, suggested that should we be able to have a "question and answer" section about astronomy on the Internet, it would be very helpful to our novice members and probably generate a great deal of interest in our website.

As I investigated the possibility of introducing such a "forum", it became obvious that the many "free" offerings of "hosting" forum pages that are available on the Internet, most, if not all, wanted to include advertising banners and links on the hosted pages. This is a practice that the MAS has always steered clear of, as the Council feels that being an internationally recognised amateur astronomical society, the MAS should not be seen to be recommending a particular product or service on it's web pages. This effectively meant that the MAS would have to program and host it's own forum, on it's own web space. The only way to run a forum type page is by using a special kind of program called a "CGI script". (CGI = Common Gateway Interface)

With both the MAS main pages and the MAS Members pages being hosted by the ISP (Internet Service Provider) 'U-net' and U-net normally not permitting the running of CGI scripts on their Internet servers without 'penalty' charges, the project appeared doomed, and was shelved in August 2001.
In October 2001, with Mike Oates having an increased personal workload due to taking a university course, I was asked if I would be willing to assume control of the North West Group of Astronomical Societies (NWGAS) website. This I did, and the NWGAS site was transferred to my web space in November 2001.

At the next meeting of the NWGAS, held in January 2002, the future direction of the NWGAS web site was discussed, and it was proposed that a "bulletin board" service be introduced, whereby the individual societies could publish items advertising any forthcoming events, without the need for me to be directly involved in creating the messages on the website. Unfortunately, this again requires the use of CGI scripting programs, and so, not wishing to pay any penalty charges to U-net, I began the search for another ISP that would be willing to run CGI scripts free of charge. This was found, and so the MAS and NWGAS sites were transferred at the beginning of February 2002. More details of this transfer can be found on page 2 of this issue of 'Current Notes'.

What will the forum look like and how will it work?

It is very hard to describe the format of a web page using words only, so I have included here an image of a "Forum" page from another web site, and the MAS page is likely to look very similar.
The system operates by requiring a user to "log in" to the site before they can "post" a question or reply with an answer or suggestion. This log in procedure will initially request the user enter an e-mail address, user name, and password. This information is used to track the user inputs and monitor usage and/or abuse.

Should a visitor merely wish to "view" the entries on the Forum, no login is required.
As can be seen from the image, it is possible to divide the forum into various topics and have those topics only contain entries relevant to that topic. This aids navigation around the forum, and avoids having to trawl your way through hundreds of irrelevant items to find the one that is of interest to you.

When is this going to happen?

Unfortunately, this type of web page is not something that one can sit down, write, and have up and running tomorrow. There is much work to be done to ensure that it operates correctly, and can be effectively monitored for abuse. I would anticipate (at present) that this forum would not be available for at least 3 months, possibly longer.

The NWGAS bulletin board system, being much easier to program as only "selected" people will be able to post items to it, is likely to be up and running much sooner.

Graham Hodson

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A New Comet on the Horizon

A new comet is set to grace our Spring skies...Comet Ikeya-Zhang. At the moment this is heading north through Pisces, but each day it will rise higher and higher away from the glow of the horizon.
The BAA comet section (see below) estimates that it will peak at around mag 3.3 at the end of March, before slowly dimming over April and May. If predicitions come to fruition, this will be the best chance to observe a comet since Hale Bopp back in 1997. The comet should be easily visible in any pair of binoculars, and may even become a naked eye object for observers away from the city.
More information (inc. extended RA / DEC co-ordinates) can be found at BAA Comet Section at:

http://www.ast.cam.ac.uk/~jds/

Another useful website with up to date images and useful findercharts is:

http://encke.jpl.nasa.gov/

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THE PROBLEM OF DEW IN OBSERVATIONAL ASTRONOMY

The only equipment really needed is a thermometer and access to radio, TV, internet or newspaper forecasts.

Making the calculation:

Let Td = dew point in °C: that is, the temperature at which dew will form during the evening/night in question. This is the value we want to calculate.

Tmax = maximum daytime temperature that occurred at the proposed observing site: this can be obtained with your thermometer or from broadcasts. If the observing site is at a different altitude from the place where Tmax was recorded, use the formula that the temperature decreases by about 3°C every 1000 feet and adjust. The site should also be within the same air mass as the recording place (within ~50 miles).

Tmin = forecasted minimum night temperature for the observing site: make any adjustment for altitude. You must assume that the forecast has taken into account the passage of any frontal systems in the meantime.

K = a constant which will be needed and is obtained from the following table:

1 knot @1.15 mph: this can be estimated.

An okta is a measure of cloud cover: 8 oktas = 8/8 cover = total cloud cover; 4 oktas = 4/8 cover = half the sky is covered etc.

Example: If wind speed is 3 knots and cloud cover 2 oktas, K = 5.5 from the table.
Tmax = 17°C (measured/reported) and Tmin = 5°C (forecasted).
First calculate Tmax / 2 = 8.5 Subtract this value from Tmin & K:
5 - 8.5 + 5.5 = 2 Now x 2 = 4. This is the predicted dew point, i.e. 4°C,
1 degree lower than Tmin.

As the predicted minimum would not be reached until just before dawn, one would not expect dew to form in this case, though no account has been made of errors. The greatest source of error would be the passage of a front. If a warm front, it is unlikely that any observing would be possible anyway. If a cold front, it would be better to read a value for Tmax shortly after the front's passage: clearing skies often follow behind a cold front. Occluded fronts are too complicated to predict a dew point value with this method, which assumes a relatively constant dew point over the period.

Once dew is expected, there are various ways to combat it. The provision of dew caps affixed to the front of the instrument helps by keeping a volume of slightly warmer air around the objective. Grass is more conducive to dew formation than bare earth, as are clay-loam-sand formations. A light wind helps stave off dew formation sometimes. A portable hair drier working off the car battery will clear away dew quickly. The eyepiece end can be a bigger problem as moisture from the eyes is always trying to saturate the air. I find that I just have to keep wiping it with a suitable cloth.

With camera lenses, one cannot start rectifying dew formation halfway through an exposure. I have found that wiring 6 x 30W resistors in series around the outside of the lens and within the lens hood and powered by a 6V DC battery does the trick nicely, acting as a low current heater without spoiling the photograph with rising currents. If the hood is rubber, it is best to staple the resistors wire sections to the hood, placing the connectors to the battery on the outside of the hood. This system has never let me down.

There is however, no substitute for a proper enclosed observatory for eliminating the dew problem.

If we were in the USA, I suspect that a value for the dew point could be freely given over the phone. Not so in this country. The meteorological office seem to have forgotten that they are public servants and are unlikely to give you the information unless you first gave them your credit card details. This is a deplorable state of affairs and it gives me great pleasure to have obtained the information and published it FREELY in Current Notes.

GUY DUCKWORTH

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Editor's extra

Astro-humour!

It is not conclusive yet, but the NASA believes the Mars Pathfinder has found proof of life on Mars.
The cd player was stolen.
---
A neutron goes into a bar and asks the bartender,
"How much for a beer?"
The bartender replies,
"For you, no charge."
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Q. How many Vulcans does it take to screw in a light bulb?
A. Approximately 1.00000000000000001
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Scientists Decode the First Message From an Alien Civilization...
SIMPLY SEND 6 TIMES 10 TO THE 50 ATOMS OF HYDROGEN TO THE STAR SYSTEM AT THE TOP OF THE LIST, CROSS OFF THAT STAR SYSTEM, THEN PUT YOUR STAR SYSTEM AT THE BOTTOM OF THE LIST AND SEND IT TO 100 OTHER STAR SYSTEMS. WITHIN ONE TENTH OF A GALACTIC ROTATION YOU WILL RECEIVE ENOUGH HYDROGEN TO POWER YOUR CIVILIZATION UNTIL ENTROPY REACHES ITS MAXIMUM! IT REALLY WORKS!
---

Where do astronauts leave their spaceships ?
At parking meteors !

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I would like to take this opportunity to thank all those members of the MAS who have sent messages of comfort and support to my dear wife Anne, during her recent illness. She continues to make steady progress and sends her love to you all.

You are in our thoughts and prayers.

Tony and Anne Cross.

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...Attendance at the October lecture by Dr Allan Chapman was not encouraged by our failure to extract a title from the lecturer until the eleventh hour; nevertheless, considering the fame of the speaker in the astronomy world, an audience of 29, including members of the public, was disappointing.
If members are finding the titles of the lectures uninspiring, then let council know. On a more positive note, our Secretary is always delighted to receive suggestions for both speaker and topic and will strive to accomodate these in future plans. This is necessarily sometimes limited by the availability of Society funds.
Members must act as their consciences dictate as far as attendance goes. However, as President, I appeal for greater effort in supporting the formal lectures. This is Your Society. It has been going for nearly one hundred years. We have hosted talks by some of the most famous names in astronomy. We intend continuing to do so. Many thanks to those who do support the lectures. A list of remaining events for this season - including our final Renold lecture - is provided below.

Guy Duckworth. President.

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1. Talks in the Godlee Observatory
Talks Start About 8.00pm

21 Mar Formal Lecture in room E7 Renold Building
28 Mar April Skies: Guy Duckworth
04 Apr Janet Maresh: Southern Constellations
11 Apr AGM Preparations
18 Apr Annual General Meeting 7:30 in the Godlee
25 Apr Society meets new council

2. Lectures in the Renold Building:

March 21st 2002at 7.30pm
Geoff Butt
(Marine Associates Ltd, Birkenhead)
"Astro-navigation"

These lectures are free of charge and membership of the society is not required. Free parking is usually available, with permission from the UMIST security staff who can also provide directions to the respective venues, upon request at the Sackville Street. security lodge.

What do you think?

As a society, by definition, we have a considerable number of members, each with their own experiences, expectations, and aspirations in their pursuit of Astronomy. As a result, the society strives to provide as wide a range of support and encouragement as possible to meet these varied needs, hoping to cater for everyone, from the occasional observer to the more advanced enthusiast. As acting editor, I have in this issue of Current Notes attempted to reflect this general ethos. However, if there are any suggestions for improvement for future issues, comments from all members of the society would be most welcome. Remember, these are your Current Notes and are meant to reflect your varied needs and interests.

RP.

MANY THANKS to those members who contributed to this issue of Current Notes. Apologies to those who for one reason or another might not be included in this issue. Contributions are welcomed from all members of the society, and can cover any aspect of Astronomy, from beginners initial experiences to more advanced aspects that members may be involved in. Remember, this is your forum for letting other members know who you are and what you're up to.

Guidelines for submissions: Please submit a copy on floppy disc or as e-mail attachment (to currentnotes "at" manastro.co.uk), in either MS Word format, or as plain text file. If possible, please also submit a hard (printed) copy. Handwritten or typed contributions alone are also welcome although, to limit the editorial workload, these should ideally be kept short in length. Finally, any data submissions (e.g. statistics from observations / measurements) should come either in a suitable digitised format (e.g. Excel spreadsheet / graphs) or with clear instructions as to how the data should be presented in the Current Notes. If in doubt, please contact the editor.

RP

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