For anyone following this... Digging into the NASA site regarding the eclipse, it appears that the circle of partial eclipse covers a good portion of the entire NA Continent. So, while the "bulls eye" of totality is fairly small (and therefore hard to hit), the size of the partial eclipse zone is very wide. It takes about 2 hrs to go from the first hint of the eclipse to when the last is gone, and any satellite crossing through that zone during those 2 hrs will experience some of the eclipse dimming. Given this, I expect that AO-73 is not the only OSCAR satellite that will experience being hit by the eclipse to some degree.
See: https://eclipse.gsfc.nasa.gov/SEplot/SEplot2001/SE2017Aug21T.GIF
So, now I wonder... Given that the zone of partiality takes 2 hrs to cross any particular location, and a satellite's full orbit is quicker than that, are any satellites going to experience the effect twice?
Greg KO6TH
Graham Shirville wrote:
Hi All,
To follow on from David's email, I can confirm that EO73 has already experienced an eclipse - this was back in March 2015. The solar panel WOD results are detailed here https://funcube.org.uk/2015/03/20/solar-eclipse-update/ and we have the records for all the available telemetry stored in the Warehouse if anyone would like more detail of what happened.
We are fortunate to have Whole Orbit Data available in addition to the Real Time channels so it should be possible to gather lots of information next month. Of course the EO-88 and UKube-1 CubeSats also carry similar FUNcube payloads so these spacecraft could also be checked to see if their orbits will "see" the eclipse.
73
Graham G3VZV
-----Original Message----- From: David G0MRF via AMSAT-BB Sent: Friday, July 14, 2017 8:18 PM To: [email protected] Subject: [amsat-bb] Long shot: August eclipse intersecting any Oscars?
Hi Greg
Sorry, only just seen your post.
I believe the answer is yes. I'll have a look at the exact pass times over the weekend.
AO-73 will fly through the path of the eclipse on the 21st August and the effects should be seen on its real time telemetry.
AO-73 has temperature and light sensors on its solar panels and this data is collected and sent every 5 seconds. You should easily see the change in light levels and perhaps, a change in external temperature as heat energy is lost as IR radiation. - Although this will depend on the degree of coverage of the sun during the satellite pass.
You may also see the total panel current ( The sum of the current supplied by the solar panels) drop dramatically. Fortunately most LEO sats are designed to handle 'eclipses' of 35 minutes, so this minor glitch in power collect should not adversly affect operation.
All of these will be displayed as graphs if you are collecting data on the Funcube dashboard. - Free windows download.
In the case of AO-73, it usually switches to transponder mode in eclipse. Will it do that on the 21st ??
Good luck. If you give it a try, let us know how you get on.
David
Hi folks,
I was asked this on our club's weekly net last week. I expect the answer is no, but thought I should check...
Will any of the ham satellites be affected by next month's solar eclipse across the USA? To be affected, the satellite's track (at some 18,000 mph) would need to intersect some portion of the eclipse (not necessarily the path of totality), which I understand is moving at some 1,500 mph. Given the speeds involved, that's unlikely. But we've got a number of satellites in sun synchronous orbits, so it's not impossible.
Any way to predict this?
If there are any, the telemetry from the event would be an awesome bit of data for students' analysis.
Greg KO6TH
p.s. I remember being at work (I think in the 1990's) during an eclipse. As I recall, the spot of totality was out in the Pacific Ocean, off the coast of Mexico. The real-time satellite weather background on my Unix workstation looked like someone had burned a hole in it with a cigarette.
Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb _______________________________________________ Sent via [email protected]. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://www.amsat.org/mailman/listinfo/amsat-bb