Late April Sun

Sunspots, Filaments, and Prominences

The first clear day after more than a month of clouds dawned on April 28th. During my solar observing session winds were light, and temperature ranged between 66 and 68 degrees. Conditions were nearly ideal.

A mysterious glitch initially made my laptop unable to connect to the telescope mount. The normal USB mount-to-computer communication port had somehow been changed. Who knows why annoying stuff like this happens? After 20 minutes reading equipment manuals I was able to establish a connection and proceed with setup.

This time of year clover mites abound. These tiny red bugs swarm over my backyard patio and garden walls. Inevitably, they end up crawling all over equipment cases. It's a mistake to squash them because they leave a red stain for every kill. I ended up sweeping them off with a Swiffer duster before bringing equipment back inside.

Giant impressive sunspots were missing on April 28th. Only one major dark umbra is visible in the slightly imperfect 12-panel disk mosaic shown next. Some nice filaments appear, including two just rotating into view on the left solar limb.

All visible sunspots can be seen in the cropped center portion of the previous mosaic. The next image can be enlarged to full size by clicking on it. The enlarged image shows nice detail because seeing was good. Biggest sunspot 4076 is above and left of center. Tiny sunspot 4077 is left of center. Sunspot 4072, featuring extremely dim twin umbras, is below center. Sunspot pair 4070 is in the lower right corner.

The next close view of sunspot 4076 with spectacular sinuous filament on the right also shows great detail when enlarged to full size.

Now let's look at some prominences. Image processing reveals prominence locations on the imperfect disk mosaic previously shown above. There are two on the right limb and one on the upper left limb. Once again, enlarging the image shows these features better.

The largest arch-shaped prominence was impressive!

A spiked-shaped prominence and neighboring limb activity showed emissions above giant emerging sunspot 4079 on the upper left limb.

A small spike prominence shot off the lower right limb.

More than a week of upcoming cloudy weather will prevent solar observing in the near future.

Mosaic/Framing Mode

Seestar Wide Fields

I'm enjoying Seestar's mosaic/framing mode lately. It's fun to roam the sky looking for opportunities to capture more than one celestial target in a single image frame. For example, galaxy M108 and colorful planetary nebula M97 appear together in the first image below. These two are separated by 48.25 arc minutes in Ursa Major. M97, a member of our own Milky Way, is in the foreground 1,700 light years away. M108 is 32 million light years distant, well beyond the Milky Way. This image, made on March 18th, is the result of 60 minutes of accumulated exposure time.

It takes much longer than 60 minutes for Seestar to actually collect 360 acceptable individual 10-second frames needed to produce the eventual 60-minute exposure. Many individual frames are rejected due to poor tracking during image capture. While using mosaic/framing mode I can usually make only one image before Seestar's battery is drained. It might take 3 to 4 hours to produce an acceptable final image, so I settle for one target per night. The beautiful thing about Seestar is how it runs successfully for 3 to 4 hours without need for personal attention. I can watch TV or read a book while interesting images accumulate.

On March 26th another entire evening was devoted to capturing (from top to bottom) galaxies M82, M81, and NGC3077. The angular separation between M82 at top and NGC3077 on bottom is 1.15 degrees. In this 90-minute exposure I should have centered the image better and moved M81 further from the edge.

On March 22nd I made another attempt to capture Markarian's Chain in Virgo. This time I made a larger field of view than a previous attempt in order to include more galaxies. The field width here is about 1.7 degrees. The next 76-minute exposure includes 23 galaxies! Some are tiny and dim. (Enlarge the image by clicking on it to see them more clearly). 23 galaxies are identified in the labeled image below. The Hubble Deep Field this is not, but it's pretty amazing for a tiny 50mm telescope in my back yard!

Leo was my next target on March 27th. Five galaxies appear in the following 60-minute exposure. On top, from left to right, are galaxies NGC3389, NGC3384, and M105 in a tight triangle. Below, from top to bottom, are galaxies M96 and M95. The angular separation between the uppermost galaxy and M95 on the bottom is about 1.3 degrees.

I was disappointed by the relatively bright sky background in the previous image, so I made a second attempt on April 16th. This time I chose a smaller field of view and tried a 90-minute exposure. In the next image M95 is not included, and the angular distance between the uppermost galaxy and M96 is about 48.3 arc minutes. The sky background does look slightly darker, but I wonder if 30 minutes extra exposure time really made a huge difference.

I'll continue to look for other wide field targets in the future.
 

Breezy March Sun

Afternoon Session

Good opportunities for solar observing are rare. I have to take advantage of each one, even if conditions aren't ideal. Such was the case on March 18th when gusty wind threatened to blow my laptop light shield box off the observing table. Wind speed diminished a bit in the afternoon, so I risked poor seeing and began imaging at 3:15 pm, EDT.

Several sunspots and filaments were distributed across the solar disc as you can see in the 11-panel mosaic below.

Significant prominences were located only in the lower right quadrant displayed in the next 7-panel mosaic.

Individual sunspot groups show well in the next two close views. First, single umbra sunspot 4030 appears near center. Curious, dim, triple umbra sunspot 4028 is to the lower right. (Click on images for a larger view.) The enlarged image shows a complex of magnetic arches to the upper left of sunspot 4030. The triple umbra in 4028 resembles a dog face!

The second close view shows a diagonal string of complicated sunspot structure above center. Running from upper left to lower right along the diagonal line are sunspots 4031, 4025, and 4022. Solitary umbra 4021 is below center. 

These images look unexpectedly decent in spite of episodic periods of bad seeing.

Galaxies in Virgo

Plus Extras

Three relatively dark moonless nights happened in late February and early March. Annoying neighbor lights were mostly off during this time, so it was a good opportunity to fire up Seestar and gather more galaxies for my Messier collection. I ended up adding eight Messier galaxies in Virgo to the other 94 Messier objects I've previously captured. Virgo contains a rich distribution of galaxies. Images below show six Messier galaxies together with companions sharing the same field of view.

First is giant elliptical galaxy M87, the brightest galaxy in Virgo. Unlike prettier spiral galaxies, M87 looks like a fuzzy ball. Elliptical galaxies have less overall angular momentum (rotation) than spiral galaxies and thus don't flatten into a disk shape. A massive black hole exists in M87's center. An incredible picture of this black hole can be viewed at this link: https://science.nasa.gov/resource/first-image-of-a-black-hole/ . 

In all the following images I'm disappointed that background sky isn't very black. Light pollution is probably the cause. I can't darken the background without also losing faint galaxy details. The following M87 image is a 25-minute exposure.

The next picture identifies three other galaxies near M87.

Two more elliptical galaxies, M59 and M60, are shown in the next picture along with six other galaxies in the same frame! See them all labeled in the second image below.

Very nice face-on spiral galaxy M61 and three companions appear next. These galaxies are labeled in the lower image.

Tilted spiral galaxy M90 with two dim companions is next. Once again, labels follow. 

The previous three galaxy portraits are 30-minute exposures. The next image is a 60-minute exposure using Seestar's mosaic mode to capture 13 galaxies in one frame! This particular group is named Markarian's Chain after the astronomer who discovered their common movement. Labels identify the galaxies. Unfortunately, I should have centered this field of view more carefully. One remaining member of the chain is missing off the upper left edge. Perhaps I'll try again soon.

Finally, I include one extra image of edge-on galaxies in Canes Ventatici. The largest galaxy is NGC4631 with small companion NGC4627 nearby. The oddly shaped galaxy near bottom is NGC4656 which appears to have a hook-like feature on its left end. The hook is actually another galaxy, NGC4657. See labels below.

At this point I've imaged 102 of the 110 Messier objects. The remaining eight are located in Ophiuchus and Sagittarius. It may be a few months before these constellations rise high enough for convenient imaging.

Galaxies in Coma Berenices

Plus One Nebula

The clear evening of February 21st was a good opportunity to try Seestar's new mosaic mode on the Seagull Nebula in Canis Major. The following 60-minute exposure barely captures the relatively faint elongated Seagull Nebula running vertically down the image's left side. The brighter circular nebula on the right is NGC2327 which features a dark lane cutting into the center that ends on the bright blue star that powers NGC2327. It took much longer than 60 minutes to obtain this image because so many individual constituent frames were rejected due to poor tracking.

As temperature dropped to 27 degrees, I pointed Seestar to galaxy M85 in Coma Berenices. (All galaxy images below are the result of 30-minute exposures.) M85 is the brightest uppermost galaxy in the next image. The bright star just left of M85's nucleus is a foreground star within our own galaxy. Below and left of M85 is galaxy NGC4394.

On February 25th skies were clear and moonless again. I set out to capture the remaining five Messier galaxies in Coma Berenices. Galaxy M88, shown in the next image, is a tilted spiral. A pair of foreground stars appear on M88's lower edge. Three other dim galaxies are arrayed on a diagonal line beginning near the left center edge and stretching down to the lower right. In order, from upper left to lower right, they are NGC4516, IC3478, and IC3476.

The next image below shows face-on barred spiral galaxy M91. Near image bottom is another galaxy, NGC4571. 

Nearly edge-on spiral galaxy M98 is centered in the next image.

One spiral arm appears less tightly bound in face-on galaxy M99 shown next.

Finally, another face-on spiral galaxy, M100, shares the field of view with at least five other galaxies. Near the right edge is edge-on galaxy NGC4312. Near the left bottom edge is galaxy NGC4379. Just left of M100 are two dim galaxies: NGC4322 above slightly brighter NGC4328. The last dim galaxy is NGC783, well separated from M100 to the upper right. Enlarge the image by clicking on it to better see these faint galactic neighbors. 

It was fun to see face-on spirals emerge as exposures continued! Coma Berenices is home to many galaxies! After these two February observing sessions my Messier collection now includes 94 members with only 16 more needed to complete the collection. Galaxies in Virgo are the next obvious targets. These should add eight more to my collection.

New Seestar Features

New Level and Mosaic Mode

Late January clear nights gave me a chance to try two new Seestar features. One was the Apertura Easy Leveler whose red adjusting screws are shown in the first image below installed between Seestar's tripod and base. Seestar must be leveled before every observing session. Accomplishing this by adjusting tripod legs was difficult and time consuming. The new device made leveling quick and easy with a few screw turns. It worked perfectly!

The second new feature was Seestar's mosaic/framing mode. This software upgrade allows users to capture objects too large to fit in the standard field of view. (Seestar's standard rectangular field of view has a fixed N-S orientation with angular dimensions 0.72 X 1.28 degrees, or 43 X 77 arc minutes.) For example, the famous Rosette Nebula, NGC2244, in the constellation Monoceros is too big for the standard field of view. You can see this in the next standard field image where only part of the full circular nebula shows up in a 60-minue exposure taken on February 3rd, 2024.

Mosaic/framing mode works by allowing the observer to expand and rotate the desired field of view on Seestar's included sky atlas before initiating an exposure. As the actual exposure proceeds in 10-second steps, Seestar moves slightly between each step, sweeping out a kind of rectangular spiral of individual overlapping exposures until it has covered the larger field of view. All these separate exposures are automatically combined and stacked to present the final larger image. On January 20th, with light pollution filter engaged, I made my first attempt using mosaic/framing mode and obtained the following 90-minute exposure of the Rosette Nebula.

As you can see, the entire nebula was nicely captured in one mosaic field of view. I have to confess being pleasantly surprised by the result! I must also honestly confess that it took more than four hours of repeated exposures to get 90 minutes of actual stacked images in the final picture! A LOT of 10-second exposures were discarded during four hours because they contained tiny tracking errors. Also, I think the nebula is dimmer than it would appear in a 90-minute standard field exposure because all parts of the nebula were not exposed for the full 90 minutes. This initial experience taught me that I may need to devote an entire night to a single mosaic image in order to get good exposure.

The Rosette Nebula image above was cleaned to remove a satellite track and possible meteor trail. In the original uncleaned image (shown below) the satellite track is in the upper right, and the meteor trail is an interrupted streak below center. Enlarge the image to see the trails more clearly. If you look closely at the enlarged image, you can see a faint extension of the meteor trail before the trail brightens in an apparent meteor disintegration.

On other nights during this late January clear spell I used Seestar in regular mode to capture five more Messier objects for my collection. Two of the five are galaxies shown below. First is a 31-minute exposure of galaxy M63 in Canes Venatici. Two other dim galaxies share the field of view. The smudge above M63 is galaxy UGC8313, and the smudge below M63 is UGC8365.

Next is a 40-minute exposure of galaxy M96 in Leo.

Finally, on January 29th, I tried a 45-minute exposure of NGC2359, also known as "Thor's Helmet". This is a bubble-shaped nebula formed by strong emissions from a powerful Wolf-Rayet star at its center. The image shows green nebulosity, but not the red fringe on the lower left edge which appears in longer exposures with bigger telescopes. I didn't know what to expect when I began capturing this. Then I was astounded to watch the image gradually emerge over 45 minutes!

After these January observation sessions I need to capture only 21 more objects to complete my Messier collection.

January Sunspots

Glorious Sunspot Display

The Sun's activity cycle has now reached a maximum. Sadly, I haven't done any solar imaging for the past three months. Most days have been cloudy. There have been a few frigid clear days, but almost every one was accompanied by strong winds of 12 miles per hour with stronger gusts. Gusts shake my telescope and blow my light-shielded laptop off the observing table. Finally, on January 17th, clear sky arrived with no wind. The temperature was about 42 degrees, much better than recent temperatures near freezing. Five sunspot groups were spread across the Sun.

The following 12-panel mosaic shows the sunspot distribution.

The next image is a cropped section from the mosaic above. From left to right across the top are sunspots 3965, 3962, and the large umbra of spot 3959. From left to right across the bottom are complex sunspot groups 3961 and 3964. This image can be viewed at 100 percent size with no loss of detail.

After capturing videos for the large mosaic above, I captured two more to construct the next 2-panel mosaic of the northeast quadrant containing four of the five sunspot groups. Click on the image to see  good detail in the full size image at 100 percent. The complicated, multi-umbra structure of lower sunspot 3961 is remarkable.

Now inspect individual sunspot portraits. The split umbra of sunspot 3959 below is interesting. Click on the image to enlarge and notice the strange fork-like dark filament whose "tines" point toward the umbra.

Again, click to enlarge complicated sunspot 3961 shown below. I can see seven individual umbras with possibly more not fully dark ones among the magnetic arches reaching across the white active areas beneath. A dramatic dark filament arch on the left adds to the scene.

In the lower right below sunspot 3964 shows a structure somewhat similar to 3961 above, but not quite as dramatic. Notice the white active area penetrating the right umbra like a piercing arrow. 

Finally, some prominences were visible around the solar limb. I processed the 12-panel mosaic above to show a few.

Although seeing wasn't particularly good for this session, I was pleased by the amount of detail available in the images above.