Summer's Greatest Hits

Well, it's Labor Day. Summer is officially over and the fall semester has begun. I got in a lot of telescope time over the summer, so I thought I would post a few of my favorite images taken during my break.

Comet 3I/ATLAS, the third ever interstellar object known to pass through our Solar System was discovered in early July. It is faint, but the Unistellar / SETI Institute citizen science program was interested in seeing if people could detect it with their telescopes. 

 

The image above shows 3I/ATLAS (circled). The individual frames were aligned on the comet, which means that the stars in the image appear as streaks. At that time the comet was about 17th magnitude, (translation: very faint!) but detectable. I am happy to be contributing to the science being collected on this mysterious visitor which, despite some claims, is indeed just a comet.

Of course, I continue to image some celestial objects just because they look pretty. Probably my favorite of the summer was this beautiful mix of stars, gas and dust known as the Elephant Trunk Nebula. 

It is located some 2,400 light years away in the direction of the constellation of Cepheus, the King. Like many nebulae, it is a region of space where new stars are forming. This was a 2-hour exposure taken with my Celestron Origin telescope. I honestly never imagined that I would someday be able to take images like this one and the others below, but I am happy to be living in the age of the smart telescope.

Much farther afield is the spiral galaxy known as Messier 33.

This is a 2-hour exposure of M33 which, at a distance of 2.7 million light years, is the second closest spiral galaxy to our Milky Way Galaxy. It is a galaxy that always challenged me when I tried to see it visually with a traditional telescope, so being able to capture it this way is wonderful.

Earlier in the summer I posted images of other nebulae, one of which was the fabulous Lagoon Nebula in Sagittarius. After further review, I thought that maybe the image I posted there, which was a 1-hour exposure, was perhaps overexposed. So, I decided to try something much shorter and I am even happier with the result. 

This image was just a 2-minute exposure! Even with this short exposure the nebula still reveals brilliant color, dark globules of dust and the young star cluster that has formed from the nebula.  

Just last night I pointed my Origin telescope at NGC 6729, a target that was new to me. It is located so far south that it never gets even 20-degrees above my horizon. Still, I managed to get a 70-minute exposure and am happy with how it came out. 

What you are seeing here are some stars that are embedded within opaque clouds of gas and just. A pair of bright, young stars are shining forth just above center while other fainter ones struggle to be seen at all. The nebula very much reminds me of the much more famous Messier 78.

At practically the other end of the sky is the more famous Bubble Nebula (NGC 7635):

The bubble at the center of the image is not a thin film of soapy water but rather of gas that has been blown off a massive supergiant star located thousands of light years away in the direction of the constellation of Cassiopeia, the Queen. Some day this star will explode forming a supernova.

Ten to twenty thousand of years ago there was a supernova explosion in the constellation of Cygnus, the Swan. It produced the Veil Nebula (a part of which is in my nebula post linked above), which is just a piece of the much larger supernova remnant known as the Cygnus Loop. 

The Cygnus Loop is about five full moons across, which means it is much, much larger than the field of view in my Origin telescope. Yet, I decided I wanted to capture it all. To do so I had to make a mosaic of 15 images. Here it is:

To me, it resembles a bubble that has just burst, but it is an expanding cloud of 'star guts' from the supernova explosion. 

I mentioned the size of the nebula above, but wanted to illustrate that with a correctly scaled image of the full Moon, so here it is: 

These were just a few of the many objects observed this summer. There's a whole lot of sky still to observe and I'll be back later with more.

A Supernova and Two Comets

We've had a wet and rainy winter and early spring. That gave way to an intense "May Gray" and a solid "June Gloom" during the first half of this month, so there hasn't been much time for astronomy this year. 

Thankfully, I had a short and fortuitous break in the clouds early in the evening of May 20th. Just one day earlier a new supernova had been discovered in M101, the Pinwheel Galaxy. I had imaged the Pinwheel last year, so I had an appropriate image to blink with the new one to show the appearance of the supernova.

That's the supernova blinking on and off on the right side of the galaxy. It is a Type II supernova, which marks the collapse and explosion of a massive star. M101 is located 21 million light years from our Milky Way Galaxy, meaning that the star exploded 21 million years ago and its light has only now just reached us. 

The rest of May remained cloudy and I wasn't able to see it again until June 15th. It's still visible. This type of supernova stays bright for many weeks, so it will be quite some time before it fades completely away.

Two faint comets have captured my attention recently. One of this is known as C/2023 E1 (ATLAS).

E1 ATLAS is a short period comet, with an orbit of 85 years. It is currently in the inner Solar System and crossing the orbit of Venus, but if you look at its orbit from the side (below) you can see that it is highly inclined (tipped) relative to the orbits of the planets.

It is a relatively faint comet, but has had an outburst recently which has made it an interesting target to observe. Below I have animated two images of the comet to show its motion against the background of the stars:

I captured the all  of images here with my Unistellar eVscope, which nicely reveals the comet's blue-green color. 

I recently targeted an even fainter comet, that *may*, in the fall of 2024, become one that will be very bright. It is known as Comet C/2023 A3 (Tsuchinshan–ATLAS). 

Here's where it currently is:

Yes, it is out past the orbit of Jupiter. Usually comets aren't observed until they get much closer to the Sun. Since A3 is at a much greater distance from the Sun than where comets can normally be observed that means that is it brighter than normal, which might mean that is will become a spectacular, dare I say, Great Comet --but not until it gets closer to both the Sun and Earth and that will not happen until the fall of 2024. 

However, it is faintly observable with a telescope right now. It's small and faint so I cropped and annotated the image so that it could be seen here:

That little dot is chunk of ice that is coming in from the Oort cloud and in about 16 months it will make a pass through the inner Solar System. As it gets closer to the Sun heating will vaporize parts of the comet which likely will give the comet a temporary atmosphere (known as a coma) and a tail or two. If it follows expectations the comet will become brighter than Venus and be easily seen without any optical aide, but comets are famously unpredictable, so only time will tell how it will really look. In the meantime, I'll be looking at it as often as I can.

It's Not Easy Being Green

The internet has been all a buzz about the "green comet" and falsely raising expectations of how it will appear in the sky.

So why are they calling it a "green comet"? That is a bit odd as all comets have a green glow about them as they get close to the Sun. I suspect that the real reason they are calling it the "green comet" is that its real name, C/2022 E3 (ZTF), is just too much of a mouthful to use and explain.

The comet has risen in brightness to the point where it can barely be seen without optical aid from a very dark sky. This is about as bright as it was expected to be, so all the hoopla about it being "bright" doesn't make much sense. Still, it looks pretty nice when photographed with a telescope.

The comet was discovered at Palomar Observatory in March of 2022. I first saw the comet August 30, 2022 when it was still more than two astronomical units from both Earth and the Sun. Here's how it looked then:

Comet C/2022 E3 (ZTF) 30 August 2022, taken with a Unistellar eVscope

 The comet and its tail are visible at the center of the image. 

I didn't observe it again until earlier this month when the comet was much closer to both Earth and the Sun. Here's a photo from early in the morning on January 12, 2023:

Comet C/2022 E3 (ZTF) 12 January 2023, taken with a Unistellar eVscope

That green color, which comes from ionized diatomic Carbon molecules, is now visible along with the whitish dust tail and a faint narrow ion tail. It is maybe easier to see the details in this animation which shows the comet's motion against the background stars:

 It has been a rainy and cloudy January and I didn't get a chance to observe the comet again until January 21st. 

Comet C/2022 E3 (ZTF) 21 January 2023, taken with a Unistellar eVscope

Again, the green glow of the comet's coma, the dust tail and ion tail are all visible, but with everything looking better than it did on the 12th. Here's an animated gif from images taken the morning of the 21st:

By January 26th the comet had moved far enough north that it was a circumpolar object, which meant that I didn't have to get up before sunrise to see it. Also, because the comet's position is changing relative to Earth, our view of the comet and its tails had changed. Below is a two-frame mosaic of the comet:

Mosaic image of comet C/2022 E3 (ZTF) 26 January 2023, taken with a Unistellar eVscope

I shot this mosaic to capture more of the comet's thin ion tail which was too long to fit in a single frame.

The comet will be closest to Earth in just a few days and when the weather clears I will try to catch it again.

The Cluster and the Comet

Back in June I posted about observing comets (see it here) and even mentioned the one that is currently closest to Earth which has this beautiful name: C/2017 K2 PanSTARRS. 

Comets have different parts to their names. The C means that is is a non-periodic comet. Once it makes this pass through the inner Solar System it is never coming back. 2017 was the year of its discovery and the K2 means that it was the 2nd comet discovered in the 2nd half of May. Comets also get the name of their discoverer. In this case that wasn't a person, but rather the Panoramic Survey Telescope & Rapid Response System, aka PanSTARRS. 

The image below shows the comet's orbit through the inner Solar System. 

It doesn't get especially close to Earth. It was at its closest a few days ago when it was 1.8 astronomical units (166 million miles) from Earth. Interestingly enough when the comet was closest to Earth it was also  nearly in the same direction in the sky as the globular star cluster Messier 10. I managed to catch them with my Unistellar eVscope 2 on July 15th.

While the cluster and the comet appear to be next to each other, they are merely in the same direction. M10 is more than 14,000 light years from Earth, but when I took this image the comet was just 15 light minutes away. That's not close at all.

Comets!

Comets are wonderful to observe. I've seen many of them over the years. The first time I ever photographed a comet was on film (Yes, I'm old). I captured comet Halley back in 1986 and comets Hyakutake and Hale-Bopp a decade later.

Probably the next comet I photographed was C/2011 L4 PanSTARRS came around in 2013. Then there was C/2020 F3 NEOWISE which was pretty good. I wasn't blogging in 2020, but I did get some decent shots of it, including this:

Self Portrait with Comet

 

Most comets aren't bright enough to see visually or capture with a DSLR camera, but there usually are several that are within easy reach of a small telescope. 

The very first comet observation I made with a Unistellar eVscope was the night of my first light: November 14, 2020 when I caught Comet C/2020 M3 ATLAS.

My settings for the telescope weren't as good as they could have been, but I was happy to catch something that I wouldn't have caught otherwise. The comet's motion in the sky made it look like a blurred streak, but you can see its tail.

The following spring a different Comet ATLAS, C/2020 R4, came pretty close to Earth. I photographed it April 28th when it was just half an astronomical unit (~47 million miles) from Earth.

In this sequence, which covers just 20 minutes of time you can see that the comet has a faint tail.

2021 also had a much more spectacular comet: Comet C/2021 A1 Leonard which was visible in our morning skies in late November and early December. It was a wonderful comet to photograph. 

Here's an animated gif of Comet Leonard that I took with my eVscope2 on the morning of December 3, 2021:

23 minutes of Comet Leonard's motion against the background stars.

 

On the morning of December 6, 2021 the comet was just 0.4 astronomical units (37 million miles) from Earth:

I again took a number of images, but this time I tried stacking them so that they were all aligned on the comet itself to hopefully bring out more detail on the comet's tail and blue-green coma (atmosphere). Here's the result:

The stars in these sorts of images always look a little strange, but I hope you'll agree that comet's tail and coma are more prominent here.

Afterwards Comet Leonard got even better, but that was a sight for observers in the Southern Hemisphere.

So when is our next bright comet coming? No one really knows. According to Visible Comets in the Future our next comet that might reach naked eye brightness is Comet C/2022 E3 ZTF which is expected to be bright enough to see in January and February of next year, though the brightnesses comets are notoriously difficult to predict. 

The brightest comet that is currently visible is C/2017 K2 PanSTARRS. Here's an image of it that I took earlier this month:

Comet PanSTARRS should be a little brighter in July when it is closer to Earth and I will be sure to take a look.

A Pair of Planets & a Comet are Rockin' the Winter Sky

If you've got clear skies, be sure to check out the continuing show that Venus & Mercury are putting on in the west just after sunset.  Here's a shot I took earlier this evening with my DSLR:

The crescent Moon will appear with these planets on January 21. The gathering of worlds should look pretty sweet.

Comet Lovejoy continues to slowly swing past the Pleiades (aka The Seven Sisters) star cluster. Here's how the looked just a short while ago:

Yeah, it's the blue-green dot under its name. It has changed it's position quite a bit since the photo I posted three nights ago. The comet is almost directly overhear now once the sky is fully dark in the evening. It has got a tail, but don't expect to see it visually. The Moon will start to ruin the view in about a week, so get out there and take a look.

Here's a link on how to spot if for yourself. You'll also see some spectacular images of the comet there this link has even more great comet pics.

Jupiter is in the sky too, being the brightest "star" in the eastern sky. This giant is best enjoyed when viewed through a telescope.  

Comet Lovejoy!

The clouds in southern Arizona have finally cleared and this evening I got a nice look at Comet Lovejoy.

Here's a 10 second shot taken with a 55mm lens showing the Pleiades (aka the Seven Sisters) star cluster (upper left), Comet  Lovejoy (greenish blob just below center) and the streak of a faint satellite (lower middle).

The comet is bright enough to be seen without optical aide from moderately dark skies, but an easy target with binoculars. It's not spectacular, but very nice and well worth look at. 

Venus and Mercury are still together in the evening sky. This isn't the best shot, but here they are with the fainter star Theta Capricorni makiing a triangle between them.

Two Planets, the Moon and a Comet

There's a lot to see in the evening sky right now. Here are a few shots that I took this evening with my DSLR camera.

As long as your weather is clear you can't miss the nearly full moon, but the other objects are a bit harder to catch.

Venus and Mercury are making a nice pairing in the western sky. Look for them as soon as it gets dark. Venus is higher and brighter and is quite easy to see. Mercury is lower and dimmer. You'll need to look for it before it sets for the night. They'll be getting closer together over the course of the next week. Take a look from night to night and you'll be able to see them pull together.

We've also got a comet in the evening sky right now too. Can you spot it in the photo above? Yeah, it doesn't leap out at you, but it is there.

This shot is cropped from the one above and Comet Lovejoy is the fuzzy spot in the oval. Even with a bright moon in the sky it isn't too hard to catch. Binoculars will help, but so will waiting a few nights. By Wednesday the comet will be a bit brighter and the glow of the moon will be out of the early evening sky. Look mid to later this week and it will be easier to find. You can get more info on Comet Lovejoy and a finder chart here.

This Evening's Moon

Was out for a walk this evening and had to hurry back to grab the camera so that I could grab a shot of tonight's thin crescent Moon.

Seeing low thin crescent hanging in the western sky, reminded me of seeing and photographing Comet PanSTARRS in March of last year.

I don't know about you, but I am ready for another comet to grace our skies.

Sunday Night's Balls of Rock, Ice and Gas

The Moon is hanging next to Jupiter this evening and putting on a nice show. Check it out:

Yeah, the Moon is overexposed here, but check out what is hanging on either side of Jupiter - Ganymede and Callisto. Not bad for a 200mm lens.

To round things out, here is your nightly pic of Comet PanSTARRS:

In spite of the growing moonlight, the comet is still an easy binocular object that is hanging on the edge of naked-eye visibility.

Saturday Comet

Comet PanSTARRS continues its passage through our early evening skies.  It remains on the edge of naked-eye visibility, but an easy target even with small binoculars.

Here are two shots from this evening:

Canon T3i, f/5.6, 200mm, 4 seconds

Here is another 4 second exposure, but cropped from the full frame.

As long as the comet remains visible and we have clear skies, I'll post pics.

Comet PanSTARRS Continues to Shine

Another evening of watching comet PanSTARRS. Both comet shots are crop from the full frame.

Canon 3Ti f/5.6, ISO 1600, 200mm, 3.2 seconds

 This time photos were taken from my front driveway. Alas, that did not provide any foreground objects to provide contrast or framing with the comet, but still it isn't too bad. Those are saguaro cacti and palo verde trees on the hill.

As it got darker and the comet got lower, I decided to push to longer exposures.

Canon 3Ti f/5.6, ISO 1600, 200mm, 6 seconds

Once the comet was down, I had to grab a shot of the Moon:

Canon 3Ti f/5.6, ISO 1600, 200mm, 1 second

Cactus Moon. Desert Comet.

It was another fine evening of comet and Moon watching from the desert near Tucson, Arizona. As the evening began the Moon appeared before the comet did. Here it is paired with a saguaro cactus:

Canon 3Ti, ISO 1600, f/5.6, 200mm, 0.5 second

 Last night the Moon was quite near the comet. By tonight the Moon had moved away, yet it was still just close enough to catch it in the same shot as Comet PanSTARRS:

Canon 3Ti, ISO 1600, f/5.6, 55mm, 2 seconds

Can you see the comet in the shot above? It is between the saguaro and the tree to the right of it. Here is a zoomed photo taken a short while later:

Canon 3Ti, ISO 1600, f/5.6, 200mm, 2 seconds

After the comet dropped too low, I took another shot of the crescent Moon with beautiful earthshine. I've cropped the full frame here:

Canon 3Ti, ISO 1600, f/5.6, 200mm, 0.5 seconds

If you haven't yet been out to catch the comet, make a plan to do so soon. Remember, it is low in the western sky. Look a 1/2 hour after sunset. While it is visible to the unaided eye, using binoculars will make it much easier to find.