Painting a Volcano Is Like Making a Volcano: Layers Upon Layers

Last month I teased a project I've been working on for a while, and having finished it this week I'm finally ready to reveal it:

I've taken up painting (with acrylics)! And I've finished my first painting!

I mused about taking up painting in this post back in June, having found the experience of painting my YTLA model at the beginning of the year to be very soothing and enjoyable. Back in August we restarted our weekly art workshops at Swinburne with our artists-in-residence Pam and Carolyn, and I decided to go for it—and I'm ultimately really glad I did, as I've found it to be incredibly rewarding.

For my first painting, I wanted to paint a picture that I've had in my head since at least 2012, back when I was working at the Visitor Information Station on Mauna Kea. It was inspired by my reading about how Mauna Kea and Mauna Loa used to host year-round glacial ice caps, and also erupted underneath those glaciers. A picture came into my mind of the summit of Mauna Kea, snow-clad, looking south towards Mauna Loa similarly covered in ice, at night with the (northern hemisphere) summer Milky Way rising majestically above while a fountain of lava erupts from Mauna Kea's summit through a crack in the ice.

I'd originally wanted to do this using Blender, like some previous projects of mine, but I just never got around to it after I started working full time so I decided I'd try doing it as my first painting project. Probably far too ambitious for a beginner like me, but you can judge how it turned out for yourself. Since I enjoy seeing the creative process I took a bunch of photos throughout the entire three-month creation period, so you can watch the entire process as it unfolded.

Here it is, my first swatch of paint applied to canvas, August 21, 2018. (Though I also spent two weeks before this applying two coats of gesso—essentially a primer layer of white paint mixed with chalk which serves as a good base for future paint layers.) Not much to look at yet, but you can see the outline of Mauna Loa and Hualālai (on the right) starting to take shape already. There's a curious thrill of trepidation that comes when holding a loaded paintbrush poised over a blank canvas; the feeling of permanence and lack of an undo option combine to make it a bit nerve-wracking even when doing nothing more complicated than a flat black night sky!

Next, I added the glacier atop Mauna Loa. The glaciers were probably the most difficult part of this project for me, as I've never seen one personally so I had to rely on photos and my own ideas of how ice looks. I think this one atop Mauna Loa came out pretty well, at least.

Of course, even personal familiarity with a subject doesn't guarantee I'll paint it well. I painted a lot of the early stages from my mental picture without reference photos, and I definitely could've done a better job with the slopes of Mauna Loa and Hualālai with some visual references. Still, this session was interesting for mixing a few different colors to play with. I'm not using pretty much any colors straight from the tube (other than the black background, and maybe some of that gray), rather I'm mixing them to start to get a grip on color mixing theory as it applies to acrylic paint.

Moving into September I finished off the slopes of Mauna Loa and Hualālai. I mixed even more shades of colors this time and started layering them over older ones, which led me to the striking realization that making a volcano and painting a volcano are very similar processes; just layers upon layers!

Almost immediately upon actually putting paint to canvas at the beginning I realized I was enjoying the process far too much to wait for weekly workshop sessions, so I quickly started working on my own throughout the week. I had a short time available for this session so I added a cloud on the left approaching from the east and crossing the Saddle. (Spoilers: I wasn't happy with it almost immediately upon finishing it, so it'll change later.)

Next session, I tackled the snow-covered summit of Mauna Kea in the foreground. A sharp-eyed inspection of this photo will reveal that it's upside-down, as I rotated the canvas on the easel so that I could paint along the bottom edge of it. It turned out to be an interesting artistic exercise, actually; I painted the smaller cinder cone on the left entirely upside-down, and am still happy with how it came out. I wasn't very happy with the glacier as a whole though, so you'll see it getting reworked.

Case in point: here I've gone over most of the foreground to try to both merge it more naturally from side to side and also introduce some feeling of contours to help define the shape. The cinder cones got some working over, too. They're actually based on real cinder cones still extant at the summit, though I didn't copy them particularly closely. The large one on the left is Puʻu Wēkiu, the eastern rim of which is today the highest point on Mauna Kea; the one behind it is Puʻu Haukea, a relatively recent cinder cone going by its not-yet-significantly-weathered dark gray color; and the one on the right is Puʻu Poliʻahu, named after one of the Hawaiian goddesses of snow. It's very close to the present-day location of the JCMT, and has a much more weathered and irregular profile now than I've painted it here.

At this point I finally started looking up references for what Mauna Kea looked like when snow-covered nowadays, and realized that photos usually showed black rocks sticking out from the snow, especially around rims and ridges. I went a little overboard with it here (and dialed it back later), but I think it definitely helps to define parts of the space better.

I was never entirely happy with the cloud I'd added, nor the center part of the foreground glacier, so in one session I redid both of them. I think it was around now that I started realizing that the composition didn't really have space for a lava fountain like I'd originally intended, but I was still on the fence about including one eventually at this point.

Instead, I decided to expand! Pam encouraged me to add a second canvas to the sky to better capture the Milky Way, and I'm really glad I took her advice. Actually painting the Milky Way was an interesting and exhausting process, as I did it by spattering paint on the canvas to make stars. (I blocked off the foreground beforehand so it wouldn't be affected.) In what's turning out to be a recurring theme, I wasn't happy with the initial look of it and spent a few sessions reworking it…

Coming into October, I went back and spattered more stars on the canvas, though I made the same mistake as before and tried to paint in the Milky Way's dust lanes from my head rather than from a reference. You might have noticed that the quality of these photos, especially regarding glare, changes a lot; it depended on if I took them in the evening after working on them under electric light, or in the morning the next day when there was daylight. Large expanses of black like the night sky here were especially difficult to properly represent the darkness of.

It's not easy to see in the photo, but I've gone and hand-painted in all the brightest stars that one could reasonably see with the naked eye based on the perspective and time of year. The center of the Milky Way roughly coincides with the center of the top canvas, so Sagittarius, Scorpius, and Corona Australis are all visible, with a bit of Lupus on the right and a few other constellations having one or two stars appearing. And being the stickler that I am, I actually painted them with colors corresponding to their spectral types. This session turned out to be surprisingly grueling, trying to put the stars in the right places based on a star map using Stellarium. I also added a few nebulae as well; the largest pink patch near the center is the Lagoon Nebula, while just above it is the Trifid Nebula. You can also see that I've subtly whited out bits of the black rims of the cinder cones to make them blend in a bit more.

I was worried that the hand-painted stars wouldn't stand out all the much from the background splatter stars, until a few days later when I noticed an interesting thing: up close to the canvas you can see all the faint background stars, but step back a few paces and it all disappears into the blackness of the night, leaving the hand-painted stars as the only ones to be seen! I definitely didn't plan that, but it works really well, and is an interesting lesson in how a painting can be seen differently at different distances; a dynamic I hadn't really appreciated from my previous experience doing artwork on a computer where you generally only look at something from a fairly fixed, nearby distance.

Finally, in one mammoth two-and-a-half-hour session I went over the Milky Way again by hand, adding gossamer stars clouds and actual dust lanes from reference photos. I spent so long looking at the Milky Way, in fact, that I now immediately recognize structures in the dust lanes in other photos from having painted them. There are still some factually incorrect dust lanes in there, but it's much more realistic now. And at this point I realized that I was satisfied with it. I could keep tinkering with it and adding more details, but I was also fine with calling it finished (I also finally decided against adding any eruption activity). I did one last session on Pam's suggestion to add a bit more color to reflect the color of the Milky Way in the ice and to push Mauna Loa more into the background, and the result is:

My first painting is complete! I varnished it just this week. The lighting on this photo is, once again, pretty terrible, but it gives a decent idea of what it's like. Together the two canvases are 80×80 centimeters (31×31 inches), so it's reasonably large. I call it “Mauna Kea a me Mauna Loa ma lalo o ka lani hōkū (Mauna Kea and Mauna Loa beneath the starry heavens).”

It feels amazing to have finally finished it, and I've received lots of nice comments on it from people. I've really dived into painting, as I've found it to be way more fun and engaging than I had expected. I've picked up a number of tubes of paint and brushes, and even a palette knife which looks like a tiny trowel and reminds me of doing archaeology! I've been reading up on techniques and painting terms, and checking out the paintings of famous painters with a new eye. (I'm thankful for a decent amount of art history in my education, but I'm learning there are so many painters I've never even heard of!)

Now that I've finally cleared that picture from my head I find another one has arisen to take its place. People have also given me some ideas for others (like a series of planetary landscapes around the solar system), so we'll see what comes next. But one thing's for sure: I expect this to be a hobby for years to come. A hui hou!

Globular Cluster Photo Series (Part 28): M55

Today I have another globular cluster picture for you, and this one just happens to be the next in the Messier catalog: Messier 55, in Sagittarius. This globular cluster is much closer than M54, at a moderately distant 17,600 light-years. It appears almost twice as large on the sky at 19.0 arc-minutes, but is a mere third its actual size at 96 light-years in diameter. It's also a lot less compact than M54 (class XI out of XII), and really looks quite nice.

Messier 55 in Sagittarius.

Not every object in Charles Messier's catalog was discovered by him (and he gave credit where it was due), and M54 is one such object. It was discovered by an astronomer named Nicholas Louis de Lacaille from an observatory in South Africa in 1752. Messier, having heard of this discovery, tried several times to locate the cluster starting in 1764, but was stymied by its low apparent height from his location in Paris (it is located 30 degrees south of the celestial equator, which makes it rather difficult to see from mid-northerly latitudes). In fact, it wasn't until 1778 – 14 years later – that Messier was actually able to find it, after which he included it in his famous catalog of objects.

All in all, M55 is a rather nice looking cluster, if I say so myself.

Globular Cluster Photo Series (Part 27): M54

It's been a while since I had any astronomical images to show, hasn't it? I haven't been able to use the imager for a while now, due to a combination of poor weather and being busy, but I do have a few images from September lying around that I never got around to reducing. Today I have the first of those, a picture of the globular cluster Messier 54 in Sagittarius.

Messier 54 is an interesting globular in several ways. For starters, it doesn't actually belong to our galaxy – or at least is a relatively recent acquisition. It appears to originate from the Sagittarius Dwarf Elliptical Galaxy (or SagDEG), a small nearby satellite galaxy of the Milky Way currently residing opposite the galactic core from us. SagDEG has four known globular clusters of its own, of which Messier 54 is the largest and main one.

Because it's on the other side of the core, M54 is the most distant cluster I've yet photographed, at a whopping 87,400 light-years away, easily surpassing the next most distance cluster I've shown here (M53, 58,000 light-years). For comparison, the Milky Way Galaxy itself is only about 100,000 light-years across. Despite its great distance, M54 still appears a relatively large 12.0 arc-minutes across on the sky, fully one-third the diameter of the full Moon. At its distance, that translates into the incredible diameter of about 306 light-years, making M54 larger than nearly every other globular cluster in the Milky Way (and certainly all the ones I've shown so far). It is also very luminous, shining with the light of 850,000 Suns, being outshone only by the brilliant cluster Omega Centauri (which is also a lot closer).

M54 is also one of the denser globular cluster, being a class III on the density scale (with class I being the densest and XII the least dense). It's also possible, according to a 2009 paper, that there may be a black hole with a mass 10,000 times that of the Sun at the center of the cluster, which is unusual for a globular cluster. All in all, it's a fascinating cluster.

Nebula, in Three Parts

Today I've got something a little different from the usual globular cluster pictures I've had a lot of recently. This is a picture of Messier 20, the Trifid Nebula, a fascinating object in Sagittarius, the Archer.

The Trifid Nebula, Messier 20, in Sagittarius.

This nebula gets its name from the way it appears divided into three parts by the dark nebula stretching across it. It got this name long before anyone knew what it was exactly, but the number three is also important to this object for another reason: it nicely illustrates all three types of nebulae.

The first type of nebulae, emission nebulae, are represented by the reddish region at the top. This red light comes primarily from hydrogen atoms in the gas being excited by copious amounts of ultraviolet light from the hot, young stars inside and around the nebula. The particular wavelength responsible is at 656.28 nanometers and is so important and wide-spread that it has its own name: hydrogen-alpha, or H-alpha for short.

The second type of nebulae is the blue reflection nebula seen below the emission nebula. These nebulae come about from starlight being reflected off of tiny dust grains in the gas cloud. The reason it appears blue is because the dust grains preferentially reflect blue light, the same way that the molecules in the Earth's atmosphere preferentially scatter blue light. Further from the young stars than the emission nebula is, the gas in the reflection nebula isn't being excited to emit in visible wavelengths very strongly.

Finally, the third type of nebulae, dark nebulae, also come about as result of dust and are represented by the dark clouds and bands of dust in front of the emission and reflection nebulae. Dark nebulae are full of tiny dust particles containing organic molecules that are extremely effective at absorbing visible light. Soot is actually fairly close in composition to these dust particles, so you have some idea of just how dark they are in visible light. Fortunately, they are much more transparent at other wavelengths, allowing us to probe their structure in infrared and radio wavelengths.

Also, to be comprehensive, there is a fourth type of nebula that typically gets its own name: planetary nebulae. These are really a subset of reflection nebulae, as they are the puffed-off atmospheres of old Sun-like stars that are being illuminated by the white dwarf core of the star, but they are different enough from typical emission nebulae to warrant their own designation.

Celestial Lagoons

Today I have a picture of the Lagoon Nebula, a lovely star-forming region in Sagittarius. It is similar in nature to the famous Orion Nebula and is similarly visible, very faintly, to the unaided eye. It is over five times larger than the Orion Nebula (110 light-years across vs. 24), but appears slightly smaller on the sky due to its greater distance (3,000-4,000 light-years away, compared to ~1,300 for Orion).

Messier 8, the Lagoon Nebula in Sagittarius.

Like the Orion Nebula, the reddish color comes from hydrogen ionized by hot, massive young stars embedded in the nebula. The blue color comes from light scattering off dust in the cloud, similar to the way air molecules scattering light causes the sky to look blue.

The Lagoon Nebula is also similar to the Orion Nebula in that they both offer looks into the cavernous interiors of gigantic clouds of cool gas and dust. From the outside these clouds appear dark and boring, and you can see that slightly around the edges of the nebula. But when young stars inside them blow away the gas around them and offer a view inside, the sight is spectacular. Not unlike geodes, now that I think about it. (Geodes, for those who don't know, are rocks that look like any other rock on the outside to the untrained eye, but which contain beautiful crystal formations on the inside if broken apart.)

Globular Cluster Photo Series (Part 14): M71

Today's picture is of the globular cluster Messier 71 in the tiny constellation Sagitta, the Arrow (not to be confused with the much larger and more familiar constellation Sagittarius, the Archer). M71 is an unusual globular cluster between 12-13,000 light-years away with a diameter of about 27 light years, fairly small for a globular cluster. It has a small apparent diameter of only 7.2 arcminutes (less than a third the width of the full Moon).

Messier 71 in Sagitta.

Sagitta is located in the plane of the Milky Way from our point of view, which explains the high stellar density in the background of this image. M71 was for a long time (up until the 1970's, in fact) thought to be a dense open cluster rather than what it actually is, a loose globular cluster. One reason was that the stars in M71 are younger than is typical for globular clusters, although that fact simply turned out to mean that M71 is a relatively young globular cluster. M71 also lacks a particular kind of variable star called RR Lyrae stars (after the prototype RR Lyrae) that are common in globular clusters, which turned out to be related to its age: its stars are too young to have become RR Lyrae-type variables yet. In fact, M71 contains only 8 known variable stars, though one of them is an interesting irregular variable.

This lack of RR Lyrae stars is one reason the distance to M71 is known to no better than a thousand light-years. RR Lyrae stars make good standard candles within our Galaxy, as the relation between their periods and their luminosities is well-known. They are also much more common than the other type of variable star commonly used as standard candles, Cepheid variables. RR Lyrae stars can be found at all angles in the sky (in contrast to Cepheids which is are strongly associated with the galactic plane), and consequently make up 90% of the variable stars found in globular clusters.

Anyway, that's it for tonight, I need to get some sleep. A hui hou!

Globular Cluster Photo Series (Part 7): M69

Today's globular cluster is Messier 69 in Sagittarius. It's a fairly small cluster only 84 light years in diameter and a mere 9.8 arcminutes in apparent size. This is because it is fairly far away from us, about 29,700 light years away.

Messier 69 in Sagittarius.

Charles Messier discovered M69 on the same night he discovered M70, on August 31, 1780 while looking for an object described by Nicolas Lacaille in 1751-2. The two globular clusters are fairly close to each other, only about 1,800 light years apart. I'll have to put M70 on my list of objects to observe when I can, so I can properly document this pair. Both of them are fairly close to the galactic core, only about 6,200 light years distant. Like many of the globular clusters I'll be showing from now on, there isn't that much else to write about it, except that it is one of the most metal-rich globular clusters known (i.e., its stars contain a higher percentage of elements more massive than helium than most other globular clusters, though still much less than the fraction of such elements in the Sun).

Globular Cluster Photo Series (Part 6): M28

Today I have an image of the globular cluster Messier 28 for your perusal. M28 is located in Sagittarius not too far on the sky from M22 between 18,000 and 19,000 light years away, with 18,300 being the closest figure I could find. It's the smallest globular cluster I've shown yet, only about 60 light years in diameter.

Messier 28 in Sagittarius.

Its apparent diameter is a miniscule 11.2 arcminutes, making this also the smallest globular cluster by size on the sky that I've shown - the full moon would appear about three times as wide as this cluster. M28 has the distinction of being the second globular cluster where a millisecond pulsar was found (the first was M4, the first in my photo series). It is now known to contain 8 such pulsars. Other than that, I don't have too much to say about it.

Globular Cluster Photo Series (Part 4): M22

Today's globular cluster is Messier 22, a nearby bright cluster in Sagittarius. Similar to M4, M22 is relatively close to us at a mere 10,600 light years, give or take a thousand. It is larger than M4 at about 100 light years across, but smaller than Omega Centauri or M13, though appearing about as bright due to its closer distance (in fact, it is the third brightest globular cluster in the sky after Omega Centauri and 47 Tucanae, just edging out M13 for the distinction). It has an apparent diameter of 32 arcminutes, making it almost the same size as the Moon, and about in the middle of the clusters shown so far. It has a somewhat smaller number of stars, only about 70,000.

Messier 22 in Sagittarius. Click for larger image.

It also has the distinction of being quite possibly the first globular cluster discovered, as far back as 1665 by an amateur astronomer by the name of Johann Ihle while he was observing Saturn in Sagittarius (M22 lies very near the ecliptic, the line the planets and Sun seem to traverse on the sky due to our perspective). Although Omega Centauri and 47 Tucanae were known well before this time (Omega Centauri as far back as the time of Ptolemy), they were thought to be simply faint stars, which is where their names come from.

M22 is also somewhat unique in that it is one of only four of the Milky Way's numerous globular clusters known to contain a planetary nebula, the wispy gaseous cocoon of a Sun-like star as it nears the end of its time on the main sequence and starts becoming a white dwarf. It's much too small and faint to be visible in my picture, though. I have some images I took of planetary nebulae within the Milky Way that I'll post when I run out of my backlog of globular cluster images. Also when I'm done with the current run of images I plan to make a little graphic showing the relative sizes of the various globular clusters we've seen.