Solar Eclipse 2024

[Graeme]

Sounds like an interesting experiment.

6th, 7th, 9th and 10th will probably all produce the same image. 7th, 8th and 9th would be good.

Also, https://photoxprt.com/best-light-meter-apps/

Graeme

[HansV]

Chris, solar eclipses on Jupiter are caused by Jupiter's moons. The four Galilean moons of Jupiter are quite large, while the sun is much smaller, seen from Jupiter. Io causes an eclipse every orbit around its mother planet.

[Graeme]

Also, other than total number of moons, ratios of planet size to moon size, surface area and orbital period, there's moon orbital inclination. Uranus orbits the Sun with almost 90° inclination so for 42 years its north pole is towards the Sun and for 42 years its south pole is towards the Sun. Its moons share that inclination so their shadows only fall on the surface of the planet around the time of the Uranium equinoxes. And its moon are named after Shakespeare and Pope characters rather than Roman gods. So that's nice too.

Graeme

[BobH]

I'm in the path of totality. The eclipse will begin ~ 12:19 hours and end ~ 14:59 hours with 3 minutes 45 seconds of totality at our location (according to this web page)

That page also reports, ominously: "Cloud Coverage (Apr 8)
In the past, this day was cloudy 55% of the time (since 2000)"

I have a reflector telescope and an iPhone and iPad. The telescope has its own mount; I have tripods and mounting brackets for the iOS devices. Anyone care to suggest strategies for capturing the event?

[Graeme]

Bob, without a solar filter any attempt at imaging the Sun, even during an eclipse is very hazardous. If you look through the telescope at the Sun you will go blind.

I would suggest putting an approved solar filter on the front of the telescope and attach your phone to the eyepiece. During totality you remove the solar filter and capture a few images. Put the solar filter filter back on before sunlight returns.

Don't forget to watch the event too!

Good luck.

Graeme

[BobH]

Thanks, Graeme.

I'll see if I can find a solar filter for my old telescope.

I was thinking of setting my iPhone on the telescope view port in time lapse mode and recording for a 10 minute period before, during and after totality while watching the eclipse with proper eyewear. I don't think the phone's camera will be affected as the human eye would be.

Your opinion, please?

[stuck]

You probably wouldn't damage the sensor on your camera but you'll probably be disappointed with the result. The sun is so bright that without a filter over the lens of your camera all you will get is a very overexposed photo, i.e a white blob. Your best bet of capturing a video of the eclipse would be to use an indirect method of viewing it. The simplest way to do that is to use a pinhole projector, like this:
    https://www.timeanddate.com/eclipse/mak ... ector.html

I made one when there was a partial eclipse in my part of the world a few years ago. If you make one a couple of days before the big event then you can practise at lining it up.

Have fun!

Ken

[Graeme]

Your opinion, please?

Here's my good friend Joe's opinion:

https://theskysearchers.com/viewtopic.php?t=33546

Graeme

[ChrisGreaves]

Also, https://photoxprt.com/best-light-meter-apps/

Thank you Graeme.
I have installed "LightMeter" and "Photometer Pro"
And there are 49 days left in which I can experiment to see which of the many readings seem to tell me the "brightness" of the light outside around 5pm, to serve as benchmarks.
I will probably start testing on April 7th
Cheers, Chris

[ChrisGreaves]

Chris, solar eclipses on Jupiter are caused by Jupiter's moons. The four Galilean moons of Jupiter are quite large, while the sun is much smaller, seen from Jupiter. Io causes an eclipse every orbit around its mother planet.

So the relative size (ratio of diameters) renders a solar eclipse on Jupiter once per moon in its orbit. That brings in the orbital periods of Jupiter's moons.
"Orbital periods range from seven hours (taking less time than Jupiter does to rotate around its axis), to almost three Earth years.", which is more mathematics than i want to get into while the driveway awaits shoveling
Basically I am not yet ready to compare Three Earth years for one moon to be mapped to the orbital periods of the other three, as well as consider which eclipse paths might overlap, to yield the probability of an eclipse on any one spot.

(signed) "getting out of my depth" of Bonavista
P.S. This is obviously a problem that needs to be well-defined before a solution is proposed, and well before one sits down at a spreadsheet processor! C

[ChrisGreaves]

Also, other than total number of moons, ratios of planet size to moon size, surface area and orbital period, there's moon orbital inclination.

Graeme, thank you for this encouraging reply Please see also my response to Hans above.

The mathematics of all this, for all the trials of the three-body problem, must have entertained mathematicians for centuries. And I suspect that high-powered parallel processing doesn't help much until the model has been defined and the model has been checked by Devil's Advocates.
Let me suppose that 25% of all post-graduate papers touch on this type of problem.
Cheers, Chris

[ChrisGreaves]

Here's my good friend Joe's opinion:

Excellent article. I enjoyed the videos.
As well I endorse the comments of "enjoy the event" rather than focusing on the technical apparatus.
I remember well the phenomena of horses, cattle, and birds wheeling in dis-array as the shadow descended so suddenly in Mount Gambier South Australia (September 26–27, 1977?).
I now know how much primitive mankind must have been alarmed when the witch-doctor threatened to "turn off the Sun".
Cheers, Chris

[HansV]

The moons with a long orbital period are very small and orbit at a large distance from Jupiter, so they won't cause a solar eclipse. The only satellites capable of eclipsing the sun as seen from Jupiter are the large Galilean moons Io, Europa, Ganymede and Callisto, plus Amalthea which is small but quite near the planet. They orbit Jupiter in 12 hours (Amalthea) to 17 days (Callisto)

[Graeme]

Every six years, during Jupiter's equinoxes the orbital plane of the four Galilean moons is edge-on with the Sun and Earth and we get what's called the season of mutual phenomena, when the four Galilean moons occult and eclipse one another!

https://earthsky.org/astronomy-essentia ... moon-2021/

If nothing else, the season of mutual phenomena is a great phrase!

Graeme

[HansV]

Great name for an indie album!

[Graeme]

Great name for an indie album!

[stuck]

Great name for an indie album!

Or perhaps a free improvised jazz ensemble?

[HansV]

[ChrisGreaves]

Another simulation: Flyover North America for the Total Solar Eclipse of April 8, 2024

BobH looms large at the 1m11s mark with the shadow strolling along at a mere 1,646 mph, but by the time yours truly hops onto the scene at 3m23s the shadow flashes by at 4,671 mph.

I suppose that the ground-speed picks up as the shadow slips tangentially off the edge of The Earth.
Cheers, Chris

[PJ_in_FL]

I'll be staying on the edge of the path at 1m21s, but plan to move to the center for viewing that day. Waxahachie, TX, would-be home of the Superconducting Supercollider that was cancelled during an era of American ignorance toward science, will have excellent viewing, weather permitting.