Showing posts with label sunspots. Show all posts
Showing posts with label sunspots. Show all posts

Saturday, April 13, 2024

April 8th 2024 Total Solar Eclipse: Sun Funnel in Use


As described in a previous post, I assembled a Sun Funnel to use on our Parks 60mm refractor with the tracking motor running to keep the Sun in the field of view as it across the sky during the April 8th total solar eclipse. 

Our family members who gathered to watch the eclipse enjoyed having an alternative to staring at the Sun through eclipse glasses. It worked great! 

In this clip, you can see the partially eclipsed Sun, a sunspot and even clouds drifting by.

Monday, March 18, 2024

Countdown to April 8th: Sun Funnel Project

As I mentioned in my last post, I have a lot of irons in the fire for the April 8th 2024 total solar eclipse! One of those is all about viewing the overall eclipse: building a "Solar Funnel" or "Sun Funnel". 

Our old telescope,  a Parks 60mm refractor we bought about 30 years ago, happens to be on an equatorial mount and has a sidereal motor. All that means is that I can point it at something in the sky and the motor ensures that the object remains in the eyepiece (with only an occasional need to adjust the direction the telescope is aimed). 

Normally, we would never point a telescope at the Sun without a solar filter but in this case it is OK: we won't be looking directly into the eyepiece. Instead what would appear in the eyepiece is projected onto a piece of rear-projection screen material, allowing us to see it safely. Better yet, more than one person can watch at the same time!

We have used a similar approach in the past, projecting the Sun onto a white piece of poster board to check out sunspots but that was kind of cumbersome. This Sun Funnel design is much easier to use. 

Ironically, while the Sun Funnel does a great job of showing the solar disk including sunspots and the Moon taking a bigger and bigger "bite" out of the Sun during the partial phase of an eclipse, it won't be something we'll pay any attention to during the "Big Show"; it will be useless during totality since the Sun will have disappeared behind the Moon!

Still, the partial phase of the eclipse lasts hours compared to totality which only lasts minutes so the Sun Funnel will get a lot of use on the 8th. 

If you have a small telescope (even if it doesn't have a motorized mount) and you'd like to build your own Sun Funnel, they are pretty simple to make and don't cost much, either. One of the most commonly referenced sets of instructions is this one from American Astronomical Society, Nightwise.org and NASA:


It has full instructions on building it, how to use it and details like the calculations for how to determine the right size eyepiece for using a Sun Funnel on your telescope. 

I finished ours the other day but today was the first time the Sun was out long enough for me to test it. If you look closely at the second picture (click on it to see enlarged), you'll see that the bright circle in the middle is the Sun, pretty much filling the entire field of view. You'll also see a number of sunspots, several just above center and another one down at the bottom.

Whether you build your own Sun Funnel or not, I hope you will be someplace in the path of the eclipse on April 8th and wish us all "clear skies"!




Sunday, October 15, 2023

October 14th Annular Eclipse as Viewed From Dallas

Did you get a chance to see the eclipse yesterday? Even though it was only a partial eclipse for us here in Dallas, Texas, it was still spectacular!

As lots of folks at the State Fair of Texas found, it's pretty amazing how easy it is to see what's going on (watching with appropriate eye protection, of course). Given that it isn't safe to look directly at the Sun and we may only even try during an eclipse, it's easy to forget that the Sun is about the same size in the sky as the Moon. That, of course, is why a total solar eclipse like the one next April is even possible. But it also means that putting on a pair of eclipse glasses and looking up yesterday during the eclipse, the piece of the Sun blocked out by the Moon was clearly obvious even without magnification. What about the view through a telescope? 

Here is a view from about an hour into the eclipse taken with my equipment which has an effective focal length of 714mm, resulting in a 12.38X view. At this level of magnification, besides the impact of the Moon being in the way you can also make out some of the many active sunspots. Click on the image to see full-size.


Seeing a point in time view of the eclipse is great but to show the changes over the course of the full eclipse, I put together this view containing a subset of all the images I shot to create the eclipse timelapse of my earlier post. These are each about a half-hour apart. 

When you click on this image to see it full-size, you'll also see another version labeled with the times throughout the eclipse when these were taken. 


Tuesday, August 29, 2017

Partial Phase Eclipse with Sunspots

With the adrenaline rush of racing 11 miles south at the last minute with Beau Hartweg to see totality through relatively clear skies, after we returned to Camp Drake, base of operations for Project Stratoclipse, I almost didn't have the presence of mind to take advantage of the fact that the clouds had finally cleared and take any shots of the partial phase of the eclipse. I guess it felt like since I'd missed the first half and totality to clouds, shooting any close-up shots was anti-climatic.

And then I remembered the sunspots. The show was almost over by the time I was set up again but I did manage to get a few decent shots before the end. The first shot is from about 6 minutes before the end of the eclipse and the second one is from less than a minute before the end (4th contact or C4). Note that in the second one there is another group of sunspots visible that were covered by the moon in the first one.

Pretty cool! Can't wait for 2024!

For anyone interested, these were shot with a Nikon D7000 and a Nikon 80-400mm lens on a (roughly) polar-aligned equatorial mount. The shots were taken through a home-made Baader film solar filter.

About 6 minutes before end of eclipse (C4), one sunspot group. 

Less than a minute left before C4, second set of sunspots now visible.