How to make inclinometer

Using a compass

SETI range calculator

VSAT information

Design and draw your own satellite beam coverage

Orbit injection calculator

The biggest lightning flash ever

Mega-Lightning flash
I use this image, from time to time, on the home page, instead of the advertisements, to give people a fright.

My impression of a 50 mile high lightning flash.

This is a real megaflash of lightning, some 50 miles long.

Safety notice:  Stand well clear, wear non-conducting rubber gloves, dry clothes and shoes, keep clear of trees, keep away from electrical fittings, do not operate machinery, do not play golf, sail a boat or climb mountains holding metal climbing sticks in the air, do not hold gamma ray sources.   Do not stand with your feet apart.  Do not jump up and down chanting "Volts jolt, amps kills" - people will think you are loopy.  Do not stand underneath the cloud - your hair might stand on end.   Hide indoors under the table and listen to your music player using its internal lithium polymer rechargeable battery !.   If you are a very long way from the storm and can see over the top of the clouds of the storm many miles away in the distance then you can peek out the window and try and photograph upper flash.  It does not last long and is not that bright so you need to do it at night with a time exposure. Some people call them "sprites".

If you can edit your own web page or web site, you are welcome to put a link to this particular page or to put a link on your web site to the image on the left.

I was in Sardinia the week of, 15th Sept 2004,  climbing at around 1800m and we got caught in two thunderstorms, which were not quite as bad as above. The guide had electric feelings in her jaw, someone else felt warm feelings and I heard hissing noises when the lightning hit nearby.  We survived all OK.   We were not listening to the music at the time and had put all metal objects down as we crouched between the heather and rocks in the rain and hail.  It was really hot and sunny down on the beaches.

Does anyone know if lightning like this causes sporadic E ionisation ?

► Page created 1st Sept 2004      Eric Johnston
Amended 13 Dec 2014

Back to large banner, rocket and satellite images