If you have any additional tips please EMAIL them to ToV@CroydonAstro.org.uk

 

More information on the transit itself is on our main Transit of Venus page.

The Most Important Tip – Safety

Observing the transit can lead to serious eye damage or blindness if you do not take the appropriate safety precautions.

o       Ensure you have a safe filter – lots of advice is available elsewhere on the web

o       If you are using a telescope make sure the filter is secure – tape it on if there is any doubt – and check the tape is still OK after a few hours in the Sun.

o       If you are using projection make sure a responsible person is there to guard the telescope at all times – children can quite easily get there head between the eyepiece and the projection card

o       Ensure any other telescopes on your mount are securely covered

o       Do NOT use eyepiece Solar Filters even if they were supplied with your telescope  - the heating from the Sun is so strong they frequently shatter exposing your eye to the concentrated power of the Sun.

o       If using binoculars ensure that the solar filters are securely held in place

o       If you are using binoculars with a solar filter it can be very difficult to find the Sun – the only safe way with both telescopes & binoculars is to move the instrument so the shadow is at it’s smallest – the instrument should then be pointing at the Sun. This means you will need a tripod or other mount for your binoculars.

o       You may well be out in the Sun for 6 Hours – you will need strong Sun block Cream & Sun block for your Lips. A Sunhat & Cool drink may also prove useful.

Remember Murphy’s laws

1: Anything that can go wrong will go wrong

2: The more important the occasion the more likely things are to go wrong

For more information have a look at these web sites here & here

Here are two examples of Murphy’s law in action from the web site – Chasing Venus

 

The Perils of Chasing Venus

Travelling across the world could be gruelling in the 1700s. Most of the transit expeditions suffered hardships, but two French astronomers were particularly unfortunate.

Guillaume Le Gentil de la Galaisière travelled to India to observe the 1761 transit from the French colony of Pondicherry. Before he arrived, the British captured the colony, forcing Le Gentil to return to the French island of Mauritius. He did not get there in time to observe the transit. Rather than return home, he studied the Indian Ocean cultures, planning to watch the 1769 transit from Manila in the Philippines. But he was ordered back to Pondicherry, again under French control. While Manila had beautiful weather during the transit, it rained in Pondicherry. Le Gentil missed both transits. When he returned home in 1771, he learned that he had been declared dead. After many expensive legal battles, Le Gentil managed to prove he was actually alive.

For the 1769 transit, Jean Chappe d'Auteroche led a party to the southern tip of Baja California. They observed the transit under ideal conditions, but a few days later an epidemic struck the area, killing three-fourths of the local population and everyone in the expedition except for Chappe and Pauly, his engineer. Chappe lingered for a short while but died before leaving Baja. Pauly managed to get back to France with all of the observation records.

We are not expecting any epidemics at Kenley – despite the transport to Kenley I don’t think you will be gone for 10 years !

Observing Tips

í     The FOV will be quite small if you are using high magnifications to get Venus a decent size - with the reversals due to both the telescope & the diagonal it is difficult to work out which way the image is up & thus which quadrant of the Sun you are looking at - Venus will not be visible before it touches the edge of the Sun. One way of testing your setup is to try it on the moon beforehand.

í     Take notes as you go - a ‘dictaphone’ will help

í     It’s almost impossible to see a TV in Sunlight - work out how you are going to shelter from the light. Here are a couple of pictures of my work of cardboard engineering – a general view and a close-up of the ‘head end’

í     It’s almost impossible to see most computer displays in sunlight – you will need a sun shelter

í     Can you focus your telescope / camera prior to Venus crossing the Sun – there may be no sunspots to help !

í     Don’t depend on Focusing on Venus before it crosses the Sun – it will be at 0 phase and be totally black

í     Can you realign your telescope in daylight if it gets knocked or the power supply fails ?

í     Have spares of everything - it’s a once in a lifetime event !

í     Put new batteries in your equipment before the start – will they last 6 hours ? If not can you change them without problems ?

í     Practice on Sunspots - if you can film these you are likely to get good results for the ToV

í     Practice - Practice - Practice

í     Record how you set up everything - photographs help !

í     Share your practice experience with others on our electronic newsgroup Altair_B

í     The transit lasts for over 5 hours so Venus will move around 90 degrees (to the right in the Northern Hemisphere) – do you have a clear field of view from where you are planning to set your equipment up ?

í     Don’t send all your valuable film off together – they may all get lost – send them to different processors at different times

í     If you are recording the pictures on a computer disc back the images up as soon as the transit has finished.

í     If you are trying to time the transit accurately beware of using the time from one of the ‘Radio Controlled’ clocks – most of them only reset their time to the radio signal once a day – in between they can drift by several seconds.

í     If you have a ‘GOTO’ telescope will the software allow you to point to Venus when it is near the Sun. Some telescopes do not have the Sun in their Database due to the risk of accidentally viewing it. The manufacturers could have added a blanket restriction on going to ban on anything close to the Sun. Just because it worked before there is still the possibility that this could have been introduced if you upgraded the telescope firmware / software.

í     Remember that your telescope / camera / projection arrangements may invert, reverse or invert and reverse the image. If you are using a high magnification check which way your image is round so that you can observe the correct area at first contact.

í     You can check the orientation of your setup on the moon – even in daylight, just beware of viewing the Sun.

í     You can use an up to date image of Sunspots on the Sun as a final check on viewing the correct quadrant. Daily Images of the Sun are available on SpaceWeather.Com, The SOHO web site and The Big Bear Solar Observatory.

í     When you are working out where 1^st contact is don’t forget to allow for the angle of the ecliptic – a lot of the diagrams show the ecliptic as horizontal.

Location:

í     Turbulence from hot ground is your Enemy – observe over water, snow or a forest

í     Avoid Bare Soil, Rock, Concrete, Tarmac, Buildings or Vehicles

í     Take precautions in case it is windy – is your tripod rigid enough?

í     Have a plan B (and a plan C) in case the weather forecast is bad

 

General:

í     Pray for good weather !