During LightSail’s brief 25-day test mission, we encouraged space enthusiasts worldwide to train their radios, cameras and telescopes on the sky to help track our solar sail spacecraft. The response was incredible, and we’re already thinking about ways we can better support your efforts for next year's flight.
Early on, I started making a conscious effort to drop the word “amateur” when describing the public radio and astronomy communities. When groups like SatObs.org started providing orbital predictions that were good enough to use in our own ground tracking efforts, the “amateur” tag felt like a disservice to your skill and dedication.
During the mission, my inbox overflowed with beacon packets, screenshots and photographs. I still have a backlog of general inquiries I need to work through, so I sincerely apologize to those of you that wrote in and didn’t get a timely answer. The level of interest was overwhelming and humbling.
This is an attempt to recognize everyone in the radio and astronomical community that helped track LightSail. If you sent us something but don’t see your name listed, please chime in on the comments and I'll try to add you to the list. Also let me know if you want your radio call sign to be added to your entry.
Ted Molczan, Cees Bassa and Scott Tilley contributed dozens of observations over the course of the mission. Ted created a special SatObs.org page dedicated to LightSail that was updated continually with new orbital predictions, and the team's orbital plots were an invaluable supplement to those provided by the Joint Space Operations Command.
Thanks, Ted, Cees and Scott, for often knowing our spacecraft's position better then we knew it ourselves.
Here's just one sample of Scott's Doppler plots:
LightSail doppler data
Cees created videos of a few of his observations:
LightSail 1 from the Netherlands, June 8
This post-sail deployment LightSail 1 flyover was captured by Cees Bassa in the Netherlands on June 8 at 01:45:20 UTC.
LightSail 1 from the Netherlands, June 11
This post-sail deployment LightSail 1 flyover was captured by Cees Bassa in the Netherlands on June 11 at 0:35:20 UTC.
The SatObs team credited their success to some of the following individuals that also sent in observations:
Ron Dantowitz, Clay Center Observatory
Andriy Makeyev in Crimea sent in videos of two laser ranging attempts. Here is one of them:
LightSail laser ranging attempt, June 7 (CubeSat form)
This video, captured by Andriy Makeyev in Crimea, shows LightSail 1 crossing the sky on June 7, 2015 at 00:20:32 UTC prior to solar sail deployment. The bright beam was used for laser ranging (no echoes were returned from LightSail). Details: EVS VNC-753-H2 CCD camera, 12cm refractor (FOV is 36'x27'). SLR station Katzively-1893, 44.3932°N, 33.9701°E, 68.7 m.
Nikolay Koshkin of the Astronomical Observatory of Odessa University sent in multiple light curves showing LightSail's brightness changes as it tumbled. Here is his last observation, where the rotational rate had increased:
Nikolay Koshkin / Astronomical Observatory of Odessa University
LightSail magnitude plot
Aaron Kingery, Bill Cooke and Robert Suggs, NASA Marshall Spaceflight Center:
LightSail sails across the sky
This video, captured by observers at NASA's Marshall Space Flight Center, tracks LightSail as it flies across the sky on June 8 following solar sail deployment.
Observers: Aaron Kingery, Bill Cooke and Rob Suggs
Bill Cooke / NASA Marshall Space Flight Center
LightSail from Spain, June 8, 3:16 UTC
This four-minute exposure of LightSail was captured June 8, 2015, starting 3:16:52 UTC from a telescope located at the AstroCamp Observatory near Nerpio, Spain. LightSail is the almost vertical line down the left side of the image, which has a 1.2 x 1.9 degree field of view (North is at top). The other satellite track is Kosmos 2360, a Tselina electronic signals intelligence satellite launched by Russia on July 28, 1998.
Equipment: iTelescope 6” (150 mm) Takahashi TOA-150 refractor equipped with a SBIG STL-11000M CCD. The telescope was pointed at the maximum height of the pass (321.3 degree azimuth, 45.6 degree elevation.
Observer credit: Bill Cooke, Meteoroid Environments Office, EV44, NASA Marshall Space Flight Center
LightSail light curve
Observers at NASA's Marshall Space Flight Center plotted LightSail's observed magnitude during a June 8 overflight following solar sail deployment. The spike from 10 to 20 seconds is believed to be a result of sun glint.
Brad Young (visual)
Alberto Rango (visual)
Leo Barhorst (camera)
Kevin Fetter (camera)
Bram Dorreman (visual, photometry)
Elena Katkova of Kazan State University used a wide-field survey telescope called the MMT in Russia:
Elena Katkova / MMT system / Kazan State University
LightSail magnitudes by MMT system, Russia
June 12 and 13
MMT System, Kazan State University
MMT System, Kazan State University, Russia
The MMT system was used to track LightSail. Vitaly Mechinsky writes the "satellite section works only due to three enthusiasts." More info: http://astroguard.ru/en/index.html
The following people recorded and submitted LightSail beacon packets. These are the automated telemetry chirps that contain health and status information from the spacecraft:
Mark Rutten, Ben Jamali and Iain Cartwright, Australia Defence Science and Technology Organisation (radio and optical tracking)
Ken Swaggart, Lincoln City, OR, W7KKE (first decoded community packet)
Mario Fazio, Argentina, LU4EOU
Eric Oosterbaan, Netherlands, PA2EON
Tetsurou Satou, Japan, JA0CAW. Tetsurou also tweeted many passes:
Finally, Cal Poly's Justin Foley gets credit for tracking LightSail from two hemispheres. Justin was in Australia during launch, but came home and worked the LightSail graveyard shift with Dr. John Bellardo for many nights after orbital operations intensified. (We could write a whole blog post dedicated to Justin, John and the rest of the team.) Justin also wins the best accompanying hashtag.
Saturday June 13th, "3:06AM-ish" local, reports Justin.
LightSail from Santa Cruz, June 9, 10:52 UTC
This image of LightSail was captured from Santa Cruz, California on June 9 at 3:52 a.m. PDT (10:52 UTC). The photo was analyzed by two additional amateur trackers for verification. Photo details: f/1.4, exposure 20 seconds, ISO 800, 30mm.
LightSail from Tahoe National Forest, California (1 of 2)
Taken from Packer Lake saddle, near Sierra Buttes, in the Tahoe National Forest, California, June 13.
LightSail from Tahoe National Forest, California (2 of 2)
A continuation of photo 1 by Kirk Bender, taken from Packer Lake saddle, near Sierra Buttes, in the Tahoe National Forest, California, June 13. LightSail is in the lower right; an airplane created the upper right streak.
LightSail from Germany
Imaged on June 14. Said Fischer: "Visually it was spectacular, at times as bright as the brightest stars, then practically invisible, and racing through the sky really fast on its low, decaying orbit. Much more impressive than any ISS pass - and the first time I saw a spacecraft less than 24 hours before reentry."
Here are some more folks that heard LightSail's signals:
Nico Janssen, PA0DLO, was one of the first trackers to identify which of the ten CubeSats launched May 20 was LightSail. He correctly identified us as ULTRASat 7, using detailed Doppler data.
Imagery master James Canvin created a fantastic top-down selfie projection using images from our day-in-the-life tests. He used the technique again to flatten LightSail's orbital sails-out image, but we ultimately learned that the booms are likely flexing a bit in space, skewing the reprojection results. Thanks, James!
LightSail DITL selfie
This LightSail "selfie" using reprojected images from the spacecraft's day-in-the-life tests was created by James Canvin.