British Astronomical Association
Supporting amateur astronomers since 1890

Secondary menu

Main menu

Home Forums General Discussion
Terms of use

NASA Survey

5 posts / 0 new
Last post
dawson's picture
Offline
Last seen: 4 days 2 hours ago
Joined: 15/03/2014 - 11:08
NASA Survey

NASA are conducting a survey of amateur astronomers to see what kind of kit we are observing with and what time of the day we use it.

It seems they are "making an assessment of the hazard potentially present to the general public as a result of NASA's satellite-based climate science lidar measurements"; this is the wording used in an email sent out by the Royal Astronomical Society.

The survey seems fairly straight forwards:

https://docs.google.com/forms/d/e/1FAIpQLSclyyQRipQ_14LPSUsaJz51SpYIwzE5p3yftkXzWkwx8oDnnw/viewform?c=0&w=1

I know nothing more about it, sorry, but I'm happy to help NASA.

James

Tony Angel's picture
Offline
Last seen: 5 months 2 weeks ago
Joined: 04/03/2014 - 23:03
Survey

I received the request too. I will fill it in, but I think that they got the tea lady/man to design it. :)

Grant Privett's picture
Offline
Last seen: 2 days 12 hours ago
Joined: 28/12/2014 - 18:30
Lidar?

I assume they are worried that a visual observer who happened to be looking down the barrel of a space based LIDAR laser beam might suffer eye damage if looking directly at it through a large telescope using the naked eye. CCDers would not be under threat.

Afterall, even if you were using a laser of a wavelength generally deemed "eye safe" then the light grasp of a 12" could massively increase the number of photons reaching your eye.

EDIT: Should have read the very end of the survey. They are indeed trying to model the risk to ground observers.

Tony Angel's picture
Offline
Last seen: 5 months 2 weeks ago
Joined: 04/03/2014 - 23:03
Damage to eyes and ccds

I must admit to telling them that I observe the Zenith quite often, both visually with the 24" and also with the CCDs.

My understanding is that lasers can damage CCDs as well as eyes.  I just did some searches on the internet to double check on this and found some confirmation of this. http://www.laserist.org/camera-sensor-damage-thesis.htm is one example.

Grant Privett's picture
Offline
Last seen: 2 days 12 hours ago
Joined: 28/12/2014 - 18:30
Damage

Yes, lasers can mess up CCDs - if you dump enough coherent energy into a device it is no big surprise they can fail.

I'm not sure what the energy density required is though.