OVER 2 YOU, 095 (27/08/02)

ADDED IMPACT

I’m a little concerned about recent reports of asteroids and comets striking the earth. Where can I find out more about the trajectories, threat assessments and hopefully some advance warning of these dangerous sounding objects?

Les Jacobs, via email

You will find all the information you need at the US and Italian-based websites Sentry (http://neo.jpl.nasa.gov/) and NeoDys (http://newton.dm.unipi.it/neodys/), as well as the International Astronomical Union Minor Planet site http://cfa-www.harvard.edu/iau/mpc.html.

UK sites, such as those maintained at the Armagh Observatory (http://star.arm.ac.uk/impact-hazard/), the NEO Information Centre (http://www.nearearthobjects.co.uk/) and Spaceguard UK (http://www.spaceguarduk.com/) provide a variety of detailed information about the impact hazard and links to other sites worldwide.
Professor Mark E. Bailey, Armagh Observatory

You don't need to worry about the trajectories of meteors heading for the Earth for three simple reasons.

1. Thousands of meteors hit the Earth every day and have done since the Earth was formed.  As they fall through the atmosphere the burn up due to friction and so nothing happens. If you have ever seen a "shooting star", that is what it is.  Pollution actually protects us!

2. We have searched such a small area of the sky for asteroids that would collide with the Earth that any data found would be meaningless. 

3. If a large asteroid was found to be heading for the Earth that would cause serious damage, then forget Hollywood there is not a single thing that anyone could do to stop it.

So relax put up your feet and forget about it.  However if you are still concerned got to http://impact.arc.nasa.gov/ 

Peter Nisbet

KIRLIAN EFFECT

Does anyone know if the Kirlian effect, whereby using a special camera the ‘aura’ generated by living things can be photographed, can be captured on a digital camera, and if so how?

S. Woodward, via email

At last a query in Connected I know the answer to! The answer is no. In fact - it can't be captured on any type of camera. Like fairies it doesn’t exist!

Peter Eyre, via email

COUNTDOWN CONUNDRUM

How can I get Excel 2000 to do a countdown specified in days, hours and minutes from the current date and time to a future specified date and time? I have been able to get either days with a decimal for hours or hours and minutes but not as I would like.
I. C. Blaik, vie email

This illustrates the fickle nature of Excel's time & date formats. However, his difficulties can be resolved thus: Suppose the 'future specified date and time' are entered in cell A1 (format appropriately to show the time as well as the date). In another cell, say C5, enter the formula (without inverted commas) "=A1-NOW()". This cell will show the number of days to go (eliminate the decimal places using 'Format,Cells, Number' or the Decrease Decimal button). In two further cells, enter "=HOUR(C5)" and "=MINUTE(C5)" to give the remaining hours and minutes respectively. The spreadsheet will update when opened and thereafter when F9 is pressed. If Mr Blaik wants the spreadsheet to update continuously and automatically, I would suggest an appropriate macro is created.
Vivian Dunn

If the future date/time is in the cell A1, enter the following formula into
another cell:
=TEXT(INT(A1-NOW()),"0")&"."&TEXT(MOD

(A1-NOW(),1),"hh:mm:ss")

This gives the time to the future date/time as decimal days followed by the
time in the format: d.hh:mm:ss. Hold down F9, and the spreadsheet will "tick".
A J Etheridge

BRAIN WAVES

Is there any device or adaptor that I can connect to my computer to monitor the various electrical signals running around inside my body, i.e. brain waves, heart beat, nerve impulses etc?

Margaret Stevens, via email

While the equipment suggested in the earlier replies (Over2you, August 6th), may enable her to display electrophysiological potentials the chances of displaying one's own brain waves, the electroencephalogram (EEG), are remote.

This is because, first, there are other voltages around the head, e.g. from muscles and the eyes, that are up to 1000 times larger than the brain potentials at the scalp surface, which are of the order of 20 to 50 microvolts. Second, correctly fixing appropriate electrodes to the scalp is not an easy job. Professional electroencephalographers have to learn how to do this and avoid unwanted artefacts from voltages generated by the electrolytic cell formed by the electrode skin interface. For this reason, DIY brain wave feedback devices are more likely to involve muscle activity than brain waves.
John Shaw

BOOK PROGRAM

Does anyone know of a reasonably priced program, which will do the necessary imposition for printing say a 12 page x A5 newsletter or a 40 page x A5 booklet from a PDF file? These are printed on A4 paper and saddle-stitched. The commercial printers have their expensive software for this, which will also do all sorts of clever tricks, but it would be useful to be able to run off a few copies as mock-ups and/or drafts for the sorts of documents we put together for our local U3A.

Don Perham, via email

I use a program called Clickbook by Bluesquirrel to create just such booklets. It works by intercepting the normal print command then providing a whole host of layouts to choose from. Once set up printing booklets is a cinch. Two passes through the printer and they are ready for stapling. Although I use it to overcome the shortcomings of MS Publisher it will work with PDF files too and is neither printer nor program dependant. The website is http://www.bluesquirrel.com/clickbook/ There is even a fully functional demo to download.
Baron P

Your correspondent should invest in an HP LaserJet - the 1100 and 1200 models come with printer driver software which will take printer output from a program - including pdf files - and print it in various forms, including booklet, which is automatically printed on A5 in landscape, and the pagination calculated so the pages form a booklet. I use this feature regularly to print A4 originals into A5 pages in a booklet (It's ideal for printing the PDF format handbooks on software supplied on CD-ROM).

Bob Bowker

I use two excellent programs for "painless printing", namely Fineprint 2000 and pdfFactoryPro available from www.fineprint.com. Fineprint 2000 acts as a printer driver so will accept output from any program that prints.  You can then view and arrange the output to suit before printing in a wide range of formats, including A5 double-sided booklet.

pdfFactory and pdfFactoryPro enable the output from Fineprint 2000 to be generated into a pdf file.  The Pro version adding security and bookmark generation. For the particular problem of a previously generated pdf file just open the file in Adobe Acrobat Reader, print to Fineprint 2000, adjust the format to your liking and print.  You could even use pdfFactory to regenerate the output in your required format, although there may be a loss of resolution.
T.N. Billson

PC MICROSCOPE

Having taken up geology in my retirement, I want to branch out into petrology, which involves using a polarizing microscope to examine thin sections of rock. However, failing eyesight (AMD) is an increasing handicap, albeit a slowly growing one.  Has anyone experience of using an optical microscope with a PC? I have Windows 95 PC with a 21-inch monitor, what other hardware would I need, apart from the microscope?  Being able to show the angular direction of the polarizer on screen with the magnified section is the dream, but not the expectation! If the idea is technically/financially beyond reach of anyone outside a well-endowed laboratory, is there a program simulating a range of rock sections?

Douglas Hague, via email

The DigiScope digital microscope has all the features he requires. It is available from Warwick Test Supplies, 69a Warwick Road, Kenilworth Warwickshire CV8 1HN, telephone 01926 851007. 

Don Wilkinson, exsell@dial.pipex.com

Douglas Hague should visit the Postal Microscopical Society web page http://www.thurlo.force9.co.uk where he will find addresses of members that will help him with his problem or redirect him. Another site worth looking at is the Quekett Microscopical Club http://www.nhm.ac.uk/hosted_sites/quekett/. Better yet join one or both clubs, he'll enjoy them. I know I do.

Tom Moore

As a first step Mr Hague might find it helpful to link his microscope to a TV.  Remove the eyepiece to set the microscope in projection mode and form an image on a 50mm diameter F/1 aspheric magnifier acting as a field lens. With careful adjustment this lens will direct the imaging forming rays through the small aperture of a digital camera the output of which can be viewed on a TV. Interesting images can be recorded and loaded into the PC where, with suitable software, they can be manipulated and quantified.  Further information on this technique, which was developed as a low cost method for quantifying laser damage and other surface imperfections can be found in the reference: L R Baker, Opt. Eng. 40(10) 2059-2060 (October
2001)
Lionel Baker

CAN YOU HELP

Since retiring I have taken up the Internet, model aircraft and model boats. Can anyone recommend a CAD program for general drawings and any specialist design programs for model aircraft and boats.

Dale Broad, via email

I have three analogue cell phones, all in reasonably good condition. The networks have long since stopped operating so is there anything I can do with them, apart from waiting fifty years for them to become collector’s items?

William Temple, via email

Does anyone know where I might obtain plans to build a ‘valve’ amplifier or radio, and also a source of valves? I remember building one as a young lad and I’m sure I would enjoy reviving the memory.

Peter Knowles, via email

Can anyone tell us (a small charity) how to print off emails showing who was sent the blind copies to? Either Outlook or Outlook Express?

Jim Hammett, via email