Laser Lights

[Sharnbrook]

We hear a great deal about how dangerous hand held laser lights are for pilots flying aircraft, and how they can temporarily dazzle air crew. Fine, but we are talking about 1 person with a relatively small, single beam unit. If that can cause a serious risk, why isn't there any risk when a laser light show of this (http://liquidmail.liquidinteractive.com.au/ch/24734/2cnjvxc/1431361/fdebbznrz.aspx) magnitude is conducted in the city centre? (Brisbane Festival next September.) This is a serious question, and I'ld be interested in knowing why there is no danger under these circumstances.

[AstralTraveller]

I suppose the short answer is that they aren't shining the laser at aircraft. :) I imagine that such a show has to assess and address any dangers or hazards involved in the show. Those lasers don't look like toys and a flash in the wrong place could be very dangerous. Fortunately I suspect they are operated by professionals and not a few dropkicks looking for quick thrills.

For the sake of our Qld colleges I just hope the show is on at full moon.

[gary]

Hi Mike,

If you did not see it, this related thread about the three week long Brisbane Festival
laser light show might be of interest -
http://www.iceinspace.com.au/forum/showthread.php?t=7602

An informal online poll by the Brisbane Times, asking respondents whether they
would like to see this become "a regular weekend event in Brisbane in order to
entertain locals and attract tourists", received 813 responses of which 80% selected
'Yes'.

See
http://www.brisbanetimes.com.au/queensland/trip-the-laser-lights-fantastic-20110523-1ezff.html#ixzz1NtDGSJ5l

With a display that is being heralded that will be seen across the city,
clearly this would be bad news for Brisbane observing enthusiasts.

As it is partly sponsored by the State Government, one course of action open
for Brisbane astronomy enthusiasts would be to scribe a letter or two to their
appropriate government representatives to voice their concerns. If nobody writes,
then as a parliamentarian said to me once, then nobody knows.

[OneOfOne]

A few years ago we celebrated New Years in the city in Melbourne. As we were walking around I could see there were a number of laser light displays shining onto the ground. It would have been very easy for a person, especially a small child, to look back at the laser. I am still dumbfounded how something like this could be allowed in a public display with many young children, but had I pulled out my trusty light sabre I would probably have been pounced on by the local constabulary!

[bartman]

In the case of lasers from a show like that hitting aircraft, I believe that the operators have to seek approval from the CAA ( ?). Checking flight paths and times. I remember when working in Broome at a nightclub we had a few high powered (normal) lights that criss crossed the sky. They were turned off before any aircraft were landing or taking off cause the flight path was very very close to the location of the club.
Cheers
Bartman

[mithrandir]

Macquarie Uni's last astronomy night had a multi-Watt (20 if I remember correctly) laser pointed at the zenith all evening.

They had arranged for all traffic to and from Sydney airport to be diverted away from North Ryde for several hours.