March 5, 2012
A Flashing Success
Flashing space station with beams of light as it passes overhead had never been successfully done—until yesterday.
It sounds deceptively easy. In an earlier post I wrote about the technical requirements. But like so many other tasks, it becomes much more involved in the execution than in the planning.
Early Sunday morning, at 01:27 our time, the San Antonio Astronomical Association, an amateur astronomy group, succeeded in flashing the space station with a one-watt blue laser and a white spotlight as we passed overhead. This took a number of engineering calculations. Projected beam diameters (assuming the propagation of a Gaussian wave for the laser) and intensity at the target had to be calculated. Tracking space station’s path as it streaked across the sky was another challenge. I used email to communicate with Robert Reeves, one of the association’s members. Considering that it takes a day, maybe more, for a simple exchange of messages (on space station we receive email drops two to three times a day), the whole event took weeks to plan.
I was ready with cameras for the early morning San Antonio pass and can report that it was a flashing success. Here’s one of the pictures to prove it:
Light (top center) flashed from the Lozano Observatory, about 40 miles north of San Antonio, was easily visible from orbit. Click on the image to see it full-sized.
I want to say I am very gratefull to Don Pettit for participating in this “flash the station” project. Members of the San Antonio Astronomical Association, working in conjunction with the Austin Astronomical Society, Sky-View Searchlights, Cooper Equipment, and the Lozano Observatory are thrilled beyond words to have achieved success with Don in this interesting experiment. We are amazed at how bright our light (1.6 billion lumens with a 1.5 degree-wide beam) appeared from space. Don was able to spot us easily from a distance of 1400 kilometers. It was an amazing experiment.
Robert Reeves
Comment by Robert Reeves — March 5, 2012 @ 1:31 pm
Would a 500mw green laser be able to be seen?
Comment by Ken Prentice — March 5, 2012 @ 4:05 pm
Don,
Many thanks for taking the time to write your blog. I enjoy reading your blog immensely. That bit “Jelly on both sides”, was priceless and just highlights how such a simple thing is so fundamentally different in the absence of gravity.
Please keep these up. I wish other astronauts had done these in the past (and if they did, my apologies and loss on missing something great).
Thanks again!
Jim.
Comment by Jim Dettman — March 5, 2012 @ 4:37 pm
That’s very, very cool.
I dropped the image into ArcGIS Explorer and, aligning the lights from the highways, plotted the laser source in the Spring Branch area, somewhere near US Hwy 381 and FM 306, where Blanco, Kendall and Comal Counties come together. Close?
Comment by Andy Hall — March 5, 2012 @ 11:02 pm
Just awesome!
Comment by Spaceport Terra — March 5, 2012 @ 11:46 pm
That’s amazing!!
I’m going to share this with my students tomorrow.
Comment by Matthew Petersen — March 6, 2012 @ 12:32 am
[...] love space. Because they’ll always have that picture you see up there, which was snapped by astronaut Don Pettit, to prove that they touched space, at least with some [...]
Pingback by Amateur Astronomers from San Antonio Flash the Space Station With a Blue Laser » Meslema — March 6, 2012 @ 3:02 am
Faildari need to fire a railgun next
Comment by Justin — March 6, 2012 @ 4:19 am
This is amazing! Its hard to believe this is the first documented successful atttempt. Huge congrats to the team.
Comment by apjb83 — March 6, 2012 @ 5:04 am
That is incredibly cool.
Comment by Bob Jones — March 6, 2012 @ 9:53 am
Is the photo of the 1-watt blue laser, or the white spotlight? I am guessing the laser due to its color, but I have also been in spotlight light at altitude and it looks blue as well. Can you confirm which is in the photo? Also, can you comment on the difference in appearance between the 1-watt blue laser and the spotlight (if you could tell one from the other)? Finally, do you know if the astronomy group used any special optics on the laser to make the beam tighter than normal (e.g., tighter than about 1 to 1.5 milliradians)? Thanks for an awesome photo and experiment!
Comment by Patrick Murphy — March 6, 2012 @ 11:34 am
[...] To see photo evidence and the full story click here. Filed Under: international space station, iss, laser pointer, nasa, san antonion Category: Science and Technology Share on facebook!Share on twitter!Send to a friend! Like More from Voice of Amarillo [...]
Pingback by San Antonio Hits International Space Station With Laser Pointer - Voice of Amarillo 940 — March 6, 2012 @ 12:50 pm
This is just awesome! I thought working ISS via ham radio would be challenging. Aligning a laser would be amazingly difficult! DE W5UGD
Comment by John M. Hoyt — March 6, 2012 @ 4:13 pm
Wicked ! Baby steps, someday it will pay off, be careful. Silly humans.
Comment by Spencer — March 6, 2012 @ 6:23 pm
[...] Air & Space via Boing [...]
Pingback by Photo From Orbit Shows Astronomers Flashing Light at Space Station — March 7, 2012 @ 6:04 pm
“one of” … So, here are more pictures, then? Will you be sharing those?
Comment by Brandon — March 9, 2012 @ 5:51 pm
[...] What a View! – http://blogs.airspacemag.com/pettit/2012/03/05/a-flashing-success/ [...]
Pingback by March 10, 2012 – Blue Light Special : What a Week! — March 11, 2012 @ 12:01 am
[...] more to that recent Space Station flash by an amateur astronomy group than may have met the eye, so here are a few more [...]
Pingback by More About That Flash | Letters to Earth — April 6, 2012 @ 10:01 am
THIS is astonishing and really thrills me…how exciting for for Don and the San Antonio group! I watch the ISS ALL the time-an addict here…he he! Happy Easter ISS and Don, when you you get this.
Comment by Kate McCue — April 6, 2012 @ 11:42 am
[...] A Flashing Success | Letters to Earth. Share this:TwitterFacebookLinkedInLike this:LikeBe the first to like this post. [...]
Pingback by A Flashing Success | Letters to Earth | Author Jolea M. Harrison — April 6, 2012 @ 6:58 pm
Hey Don – Any idea what distance the ISS was from earth when the laser was spotted??
Thanks
Comment by Michael Bamford — April 11, 2012 @ 5:53 pm
how high was the space station when that happened
Comment by john smith — April 12, 2012 @ 7:30 am
Don, Great blog, it is really fascinating that this has been successfully accomplished. Now I wonder what size would a mirror have to be in order to flash the sunlight to the ISS and be visible from orbit? I have heard of windows of greenhouses being visible on satellite images.
Comment by Wim Holwerda — April 26, 2012 @ 5:02 pm
How large or powerful of a light source would you need to have to make it visible by the naked eye from space?…
Due to the phrasing, I can see two possible questions that might be intended here. 1) Because of the mention of the saying “It can be seen from space” the question might be about the smallest object in orbit that we could see from the ground, with th…
Trackback by Quora — September 24, 2012 @ 4:56 pm
Hello Don,
I first saw a story about plan to flash ISS, and then this picture. My first reaction was, omg what are they plan to do.
Now, i see that you guys have everything planed, and also to take a flashed photo.
I thought that even on that huge distance, the beam will be less than 1Km wide. Viewed from Earth, you have feeling that the beam will be no more than 100m wide, even if you know about spreading angle and distance.
Keep with your blog, we are enjoying reading it.
Also, say hello to you ISS fellows
Comment by lol — October 14, 2012 @ 9:41 pm