the fellowship of the observatory

in which i reveal to those interested baltimorians the nature of the cosmos. and now my watch is over.

Do you remember the first time you saw the sky unaided? Perhaps, perhaps not. The firmament hangs above us all our lives, and we’re blessed with the opportunity each clear night to glance upwards and see some hint of a universe out there. For most, this first glance is lost to deep memory, or forgotten entirely. What might remain, within recall? What might recapture that awe and wonder long since forgotten? What might evoke that feeling in a child, old enough to remember the experience in their future years? The aid of the eye: a lens, a cylinder, a nesting doll of mirrors?

To put it succinctly, might someone’s first memories of awe at the night sky be thanks to a telescope?

If you’re like me, and many billions of people, you might have grown up somewhere bright and shining, where the buzzing lights of major cities claw their way upward and blot out the sky at night. Like me, your favorite constellation might be Orion, his component stars bright enough and distinctly patterned to be recognized even in the dense urbanity. Beyond Orion, the rest of the sky might fade away, single bright stars removed from their lattice. Wandering planets, blazing with the Sun’s bouncing light, might be all that is left to the eye, and as they move with no backdrop, erase all record of reference frame.

Why then, the telescope? When we are painting over the night with satellites and LEDs, we disconnect ourselves from a hundred thousand year homo-sapien science. For many, like myself, living in Baltimore without ready or safe access to the clearer skies of rural America, the telescope becomes a portal, through which time and space unfold, become messy.

Normally, in American Ph.D programs in astronomy and physics, instead of paying for tuition, you’re actually an employee. You take classes, sure, but most of what you do is teach and do research, both of which are productive tasks whose fruits are enjoyed formost by the institution (like any other job). So, Ph.D students in this field in this country are “guaranteed” a (meager) stipend. In many departments, the default way to earn the stipend is by being a teaching assistant. If you or your advisor has a grant (from, for example, NASA or the NSF), you can use that grant to pay your stipend, on the condition that you produce a certain kind of research for that grant money. Either way, you’re expected to produce research in order to further your thesis and your career (so you could imagine that having to teach and research in order to earn your stipend is more difficult than just having to research). In some cases, other jobs around the department or university might cover your stipend. I spent the last year as the Observatory Fellow at JHU, running the Maryland Space Grant Observatory in order to earn my stipend.

The position entailed keeping the observatory running, loaning out keys and providing tech-support to overzealous undergraduates, hosting a high-school intern, and conducting outreach events each week. Sometimes, these events were tours for K-12 classes or interviews for school projects, but each (clear) Friday night we would put on an “open house” where anyone was free to visit the observatory and use our instruments to observe the night sky. These often resembled planetarium shows, with a particular topic (planets in the solar system, or clusters of stars, or nebulae, or galaxies) that I would present to groups in the observatory dome while guiding their viewing.

I had some experience with operating a telescope like this before, and plenty of experience using cameras on smaller telescopes to take data, but the social aspect of this job was new and challenging to me.

image of Jupiter, my work

Early in the school year, during late summer and fall, the giant planets were visible in the early evening, and I could attach eyepieces to the largest telescope at the observatory, inviting guests to see the bands and spot of Jupiter, or the rings of Saturn with their own eyes. As long as it was relatively clear out, people’s response was immediate and positive. Looking through an eyepiece has a tactile appeal; because of the haptic feedback, and because you’re “seeing” through the telescope. The job was the most rewarding when I could help a kid up the ladder to the eyepiece and hear them exclaim “ooh!” or “whoa!” after seeing a planet.

As the year progressed, the giant planets fell out of view, and even through a half meter telescope, everything visible to the human eye began to resemble points of light (except Venus and the Moon, which weren’t always visible). We began rely on our observatory cameras, which can expose for much longer than the human eye can, and therefore can observe much fainter things. The problem with this is a few-fold. The haptic feedback is gone, and looking at something on a screen just isn’t as interesting as seeing it with your eyes. The number of interesting things in the night sky is technically infinite, but realistically (for our constraints) incredibly narrow. We need something bright enough to show up in ~1 or 2 minutes of exposure time, something nearby enough to show structure, and something compact enough to not be washed out by light pollution.

For example, the Andromeda Galaxy looks beautiful through the Hubble Space Telescope, and while its very bright, it is spread over a large patch of sky, and very diffuse. Taking a picture with our setup, it would look like a blurry blob.

image of the Orion Nebula processed by our intern M. Prem

We had better luck with bright nearby nebulae, because we could use narrowband filters to cut out a lot of light pollution, but these weren’t present all year (Orion set after about March). It came to “galaxy season,” the late spring in the northern hemisphere, which is a favorite time of year for many astrophotographers. For us, it was the most difficult, because galaxies have basically the same color (white-ish) as light pollution does, and get completely washed out under even moderately poor viewing conditions.

C/2022 E3 (ZTF), a comet. Images taken by myself, processed by M. Prem.

By far the most difficult night of my fellowship was February 3rd, 2023. The comet night. C/2022 E3 (ZTF) made the news early this year for being a relatively bright, green comet that has a very long orbital period (50,000 years, which led some to call it the “Neanderthal comet”). It was projected to be visible with the naked eye for a night or so, as it passed near the Earth, and indeed from dark sky sites (like national parks) it was observable. Our open house that week missed its peak observability by a few days, but the comet was still bright enough to take pictures of.

You never know, as an astronomer, which seemingly mundane happenings in the field will make it mainstream. I didn’t expect C/2022 E3 (ZTF) to be a very big deal, since just a few years past the much brighter Comet NEOWISE made such a splash. People were excited about C/2022 E3 (ZTF) though, and wanted the opportunity to take a look for themselves.

Unfortunately, events conspired against us that evening. Nearly 250 people attended, more than quintuple our average attendance. That night was one of the coldest nights in Baltimore that winter, reaching 15 °F, below freezing. We couldn’t have anyone on our rooftop deck where we normally have people wait their turn, since they’d freeze, and it wasn’t much better in the observatory dome. My boss and a few volunteers from the department had to use a ticket system to keep track of people, and send them up in groups. I was up in the dome the entire time, and my feet went numb.

The comet was faint, the moon was full, the nearby statium lights were on, and there was some haze from the bay. So we needed to use a camera to see the comet at all. In order to show it to so many people, I projected the camera view onto the inside of the dome, but the “live view” was just that, another screen, another virtual experience with no haptic feedback. Many people enjoyed it, but with nearly hour long waits for some, many people voiced their disappointment.

Then the dome motors froze, and the observatory stopped moving. Apparently that can happen when it gets too cold. So, the telescope, tracking the moving comet dutifully, began drifting back under the embrace of the dome, away from the night sky. We “got out and pushed” so to speak, but with increasingly diminished returns. We were able to keep the telescope mostly unobscured until the end of the event, but barely, and probably strained the dome in the process.

For as much as that one awful night is burned into my brain, however, I’ve certainly lost track of each and every wonderful small interaction, with a kid so genuinely interested in astronomy or a parent rediscovering whimsy. I remember some of them very clearly, and others not at all, but the observatory fellowship grounded astronomy for me during a challenging year. Often I feel like astronomy doesn’t matter, or more particularly, that the ways we practice astronomy under capitalism are fundamentally flawed, and at odds with astronomy as a necessarily (but not uniquely) human practice. When I had these strong doubts, I could ground myself by sharing the little I know about the sky with others.

Now, I leave the post in capable hands, and on to my thesis research.

Until next time, clear skies.