Astronomy and laser pointers

[AstroLaser]

I'm an amateur backyard astronomer and thought it would be neat to see what articles I could find related to astronomy and lasers.

Here is some of what I found, some relate to laser pointers and some to the use of other lasers in astronomy.

(I know there are other astronomers on the forum and they should especially enjoy these articles

(quote)
"Green laser pointers are the best way we have found to point out objects in the night sky to the public," says Monty Robson, a commercial airline pilot and avid amateur astronomer. He regularly conducts observing sessions for high-school students and their families at the John J. McCarthy Observatory in Connecticut. "I would be very disappointed," Robson adds, "if these useful educational tools became restricted by law." Amateur astronomers can help minimize the risk of such an outcome by using common sense, following the safe practices outlined above, and educating others about the safe use of laser pointers.
(end quote)

source of the above quote: SkyandTelescope.com - Observing - Some Pointers on the Use of Laser Pointers


(yea ! - I'd really like one of these chairs in the next article ! - see photo in article at link below)
(quote)
The joystick also controls a built-in green laser pointer that helps you aim at specific sky locations or shows you where you're looking when you happen upon an interesting object while randomly sweeping the sky.
(end quote)

source for the above quote: SkyandTelescope.com - Equipment - Laid-Back Astronomy

(quote)
Like many of you, I never head off to a star party without my trusty green laser pointer close at hand. These great and increasingly inexpensive gadgets have really revolutionized how we point out sights in the night sky to newbies and veteran skywatchers alike.
(end quote)

source of the above quote: SkyandTelescope.com - Observing Blog - Green Lasers: A Hidden Danger

(hey, maybe some of you can aim for the reflector on the moon mentioned in the next article
(quote)
Since Apollo deployed laser retroreflectors, astronomers have routinely used them to track how the Moon is slowly moving away from Earth. This helps scientists develop a better understanding of the processes that are causing this motion, including what's occurring inside the Moon's core and the tidal motions on Earth.
(end quote)

source of above quote: Astronomy.com - Lunokhod 1 retroreflector found

(quote)
From their observatory on Mount Hopkins south of Tucson, Arizona, Hart and his group point a bundle of green laser beams into the night sky. Some of the laser light bounces off oxygen and nitrogen molecules high up in the atmosphere, creating five artificial stars spread across the field of view.
(end quote)

source of above quote: http://www.astronomy.com/asy/default.aspx?c=a&id=10113

(quote)
The instrument is designed to detect dust, clouds and fog by emitting rapid pulses of green laser-like light into the atmosphere. The light bounces off particles and is reflected back to a telescope.

"One of the main challenges we faced was to deliver the lidar from the test lab in Ottawa, Canada, to Mars while maintaining its alignment within one one-hundredth of a degree," says Whiteway. "That's like aiming a laser pointer at a baseball at a distance from home plate to the center field wall, holding that aim steady after launch for a year in space, then landing," he adds.
(end quote)

source of above quote: Astronomy.com - Mars lander gets instruments ready for operation

(quote)
The group plans on purchasing a 6-inch reflecting telescope; a solar telescope for viewing features on the Sun; four binoculars, two 10x50 and two 8x42; two eyepieces with Moon filters; 75 star and planet locators; and a green laser pointer.
(end quote)

source of above quote: Astronomy.com - Astronomy names 2007 "Out-of-this-world" Award winner

(quote) (this one is past dated, but perhaps they'll have more such events again)
Dates
December 26, 2009 - December 31, 2009
Time
11:00 AM- 4:00 PM
Event
HOLIDAY PLANETARIUM PROGRAMS
Location
New Jersey, USA
Description
The Newark Museum will present holiday planetarium programs and laser shows on the hour from 11:00 a.m. to 4:00 p.m. December 26 through 31. Explore the seasons, the winter solstice, as well as holiday music illustrated with wonderful laser imagery.
(end quote)

source of the above quote: SkyandTelescope.com - Event Calendar - HOLIDAY PLANETARIUM PROGRAMS

 

[Petacat]

Hi Astrolaser:wave: Man it will take me a while to work through all these resourses. Thanks for the links. I used lasers to aim my scopes and point out things in the sky many years ago while living in Alaska, but don't anymore. They were great for these purposes. But, since I moved down here to the lower 48 states I have gotten complaints at Star Partys about them.
I will never point a laser at the sky again , not even a 5mW, because of the bad press about them and fear of the goverment. They won't care that I was pointing out a planet to someone if I accidentally hit a aircraft flying through the beam. No, lasers in astronomy has been ruined for me. you can take your chances if you want, but now me. Never Again.

 

[AstroLaser]

Hi Astrolaser:wave: Man it will take me a while to work through all these resourses. Thanks for the links. I used lasers to aim my scopes and point out things in the sky many years ago while living in Alaska, but don't anymore. They were great for these purposes. But, since I moved down here to the lower 48 states I have gotten complaints at Star Partys about them.
I will never point a laser at the sky again , not even a 5mW, because of the bad press about them and fear of the goverment. They won't care that I was pointing out a planet to someone if I accidentally hit a aircraft flying through the beam. No, lasers in astronomy has been ruined for me. you can take your chances if you want, but now me. Never Again.

Hey Petacat !!!

I have heard that some star parties frown upon their use (more likely ones where many people are taking long exposure astrophotos and don't want a beam in their photo

but there are star parties that do use them, one article I read suggested limiting the time frame they are used to the first part of the evening (to show newbies where some things are).

Anyhow, I believe that used with caution they are legitimate tools for astronomy.

The one article I posted even quotes a commercial airline pilot (who is also an amateur astromoner) defending their use (with caution of course) so what better supporter can we have than that !

(quote)
"Green laser pointers are the best way we have found to point out objects in the night sky to the public," says Monty Robson, a commercial airline pilot and avid amateur astronomer. He regularly conducts observing sessions for high-school students and their families at the John J. McCarthy Observatory in Connecticut. "I would be very disappointed," Robson adds, "if these useful educational tools became restricted by law." Amateur astronomers can help minimize the risk of such an outcome by using common sense, following the safe practices outlined above, and educating others about the safe use of laser pointers.
(end quote)

source of the above quote: SkyandTelescope.com - Observing - Some Pointers on the Use of Laser Pointers

I have an idea that I will post in a seperate post.

 

[Tech_Junkie]

In the US anything 5mWs and under is OK to point in the sky. Obviously not at a helicopter, but planes fly so high the power, and beam spread out so much that its more than likely the pilot wont even notice it.

 

[AstroLaser]

Here is a really neat idea to help educate non-laser folks who question your use of green laser pointers outside at night -

There are sincere folk who simply don't know that green laser pointers are indeed legitimate tools for amateur astromoners and might question your use of them, if this happens, be polite and show them a copy of the article at the link below (print it out and highlight the paragraph that quotes the commercial airline pilot defending their use).

Tell them you carry a copy of the article because you realize the average person might not realize they are legitimate tools of amateur astromoners.

What better supporter of green laser pointers can you have than a commercial airline pilot defending their (responsible) use !

(highlight this part of the article after you print it out)
(quote)
"Green laser pointers are the best way we have found to point out objects in the night sky to the public," says Monty Robson, a commercial airline pilot and avid amateur astronomer. He regularly conducts observing sessions for high-school students and their families at the John J. McCarthy Observatory in Connecticut. "I would be very disappointed," Robson adds, "if these useful educational tools became restricted by law." Amateur astronomers can help minimize the risk of such an outcome by using common sense, following the safe practices outlined above, and educating others about the safe use of laser pointers.
(end quote)

source of the above quote: SkyandTelescope.com - Observing - Some Pointers on the Use of Laser Pointers

Again, even though green laser pointers are legitimate tools for amateur astromoners we must remember to be very careful to watch for planes, scan the sky first before pointing somewhere)

 

[AstroLaser]

In the US anything 5mWs and under is OK to point in the sky. Obviously not at a helicopter, but planes fly so high the power, and beam spread out so much that its more than likely the pilot wont even notice it.

Thanks Tech_Junkie !

That helps answer a question I had been planning on asking.

As far as 5mw green lasers, how low would a plane have to be before there might be concern of it affecting a pilot ?

....if you can make out the wings of the plane, (see the distinct red and green lights of the wings at night) ?

If the plane is so high as to appear as a large star moving across the sky you are saying it probally would not notice ?

(of course it might still be best to err on the side of caution and wait for any plane to pass no matter how high)

 

[Tech_Junkie]

Obviously you should never point it at anything flying in the sky.

I was talking about the airliners that are up past the clouds that are not easily seen.

 

[AstroLaser]

Obviously you should never point it at anything flying in the sky.

I was talking about the airliners that are up past the clouds that are not easily seen.

Agreed !

A side question you response made me think of -

On a cloudy night is a 5mw green laser capable of reflecting off the clouds, or do most clouds never usually get low enough for a 5mw to relect off of them ?

(I just recently got my first green laser pointer - 5mw)

 

[Tech_Junkie]

On a cloudy night is a 5mw green laser capable of reflecting off the clouds, or do most clouds never usually get low enough for a 5mw to relect off of them ?

I highly doubt it. 5mW is not that bright. I had a 200mW Blu-Ray and could just barley see it on the low clouds going by on the sea cost. It was not green, but it was 40X the power of a 5mW.

 

[AstroLaser]

Side note:

For those of you who might only be casual night sky observers try looking at Jupiter or Saturn with even a small telescope, I remember how neat it was the first time I saw the rings around Saturn "live" and also 4 of the moons around Jupiter.

Even a pair of 10x50 binoculars can give you a "wow" view of things like the Pleiades (looks almost like a handful of diamonds !)

.....you just might add amateur astronomy as another hobby !

(a hobby where you can use your green laser pointer !)

 

[AstroLaser]

On the topic of light being projected in the sky - I don't think they are used as often now, but I remember occasionally stores, car lots, ect. would use giant search lights sweeping around the sky in a circular motion to attract attention to a big sale or grand opening and you could see those beams from miles away.

Anyone remember those and have you seen any stores use them recently ?

 

[AstroLaser]

Also reminded me of all the unnecessary "light pollution" from improperly constructed street lights that don't shield light from going upwards where it's not needed.

The night sky is getting so light polluted that many people in urban and even suburban areas can not enjoy the beauty of a dark night sky where you can actually see a lot of stars.

There is even an organization trying to preserve the night time view of the stars -
(International Dark Sky Association)

IDAHome

(besides, if the night sky gets too light polluted from improperly shielded street lights, there won't be many stars visible for a lot of people to point out using their green laser pointers)

 

[Tech_Junkie]

Astro use the 'edit' button to combine/add posts. Double, and triple posting is frowned upon.

 

[AstroLaser]

Astro use the 'edit' button to combine/add posts. Double, and triple posting is frowned upon.

sorry, I guess I could have edited the previous post to include what I wrote in the next post since it was related.

(bear with me, I'm still fairly new here - but learning

 

[Petacat]

Having come from alaska to the east cost the lack of a night sky is astonishing, and depressing. The people here don't even know what has been taken from them. Even the richness of a laser beam after sunset has been deminished due to light pollution.:scowl:

 

[AstroLaser]

Having come from alaska to the east cost the lack of a night sky is astonishing, and depressing. The people here don't even know what has been taken from them. Even the richness of a laser beam after sunset has been deminished due to light pollution.:scowl:

That is indeed sad, I have heard of people visiting dark sky areas away from light pollution for the very first time and being so amazed at all the stars they could see.

Probally relatively few people have ever seen the Milky Way because of all the light pollution in most areas.

Wow, you mean there is now that big of a difference between West Virginia and Alaska ?

Do you live in or close to a large city ?

I remember roughly about 20 years ago my wife and I drove a friend to the mountains of West Virginia so they could check out some land they were seeing about buying, it must have been really far from any artifical lighting because when we got there at night it was so dark you could even see the Milky Way really good (and that takes a pretty dark sky). (when the lightning bugs lit up it was almost like someone shining an led bulb because of the contrast to the darkness, it was really dark !)

(and those twisting turning roads thru the mountains was almost being on a roller coaster

I just wonder how brilliant my green laser pointer would have looked if I had one way back then when we went there to the mountains of West Virginia !

Here are some light pollution related links I found doing a Google search:

Light Pollution

http://darkskyinstitute.org/light.html

The World Atlas of the Artificial Night Sky Brightness

Growing light pollution washing out South Shore's night sky - The Boston Globe

Light Pollution