I got my first telescope in 2017, in time for the Great American Eclipse. I started paying attention to the concept of light pollution, including finding detailed maps of what places had high or low amounts of light pollution. After looking up nearby areas that were potentially good for stargazing, I got curious, and started just looking around at what all the light pollution was from. Of course, the vast majority of light pollution is from cities: street lights, industrial zones, parking lots. But sometimes, it’s from something else.

Maine

My first find was when looking over my home state of Maine. At first glance, everything looks normal. Bright spots for the two biggest cities, Portland and Bangor. Scattered lights over the whole coast. Pitch black over Baxter State Park.

But wait, what’s that other bright spot? It looks almost as bright as Portland. I’m not familiar with a city there.

Zooming in, we can see that it is… nothing. Just a bend in a river.

Switching to google maps satellite mode, we can see that there definitely isn’t a city there. But there is this large, flat building.

What kind of building produces a city’s worth of light pollution? At the time it wasn’t labeled on google maps, so I switched to street view and tried to find signs. I googled random guesses. Somehow, I found it. It’s a tomato farm called Backyard Farms. The tomatoes are in a massive green house. And while most of the time the tomatoes grow by sunlight, the winter hours in Maine are very short, and so this greenhouse augments its growing season with an enormous array of yellow lamps. And this makes it the single greatest source of light pollution in the entire state.

North Dakota

If you looked at this light pollution map of the United States, you might start to wonder after a minute; what is this sprawling metropolis in North Dakota?

Zooming in, we can see that its location is not the only odd feature. While the light pollution of most urban areas is relatively smooth and peaks in a small number of central places, this phenomenon seems to be quite blotchy.

Again, switching to google maps, we see an intense lack of urbanization. Zooming in all the way reveals the truth.

If you don’t recognize the shadow, this is an oil field. The light pollution comes from the associated gas flares. These flares are deliberate, continuously burning fires, and they convert methane, a potent greenhouse gas, into CO2, a much less potent greenhouse gas.

While the entire subject is rife with controversy, oil fields continue to shape our landscapes. Here’s a strange looking nebula in Texas.

And here is a constellation of offshore oil rigs in the Gulf of Mexico.

Hawaii

Lastly, I was wondering to myself what the light pollution around Mauna Kea looked like. Mauna Kea is a mountain in Hawaii that hosts a dozen of the world’s finest astronomical observatories. It has near-perfect viewing conditions, including being above most of the water vapor in the atmosphere. But it still shares an island with two hundred thousand people, who are producing a noticeable amount of light. So what does the map say?

Panning over to Hawaii, we see that Honolulu is by far the biggest source of light pollution. Fortunately, it’s over 200km away from Mauna Kea, and doesn’t contribute to light pollution there. But the big island does seem to have its own major source. What could it be?

Zooming in, we see that it’s pretty point-like, symmetric and centralized. But there’s no city there.

Instead, there’s a volcano. Kīlauea, as an active volcano, regularly has literal glowing lava occupying the caldera. The amount of light changes with the level of eruption activity. Fortunately, at least according to the map, the light pollution doesn’t quite reach the summit of Mauna Kea.

 

Like daytime satellite mapping, night time light pollution maps are an extremely useful tool. Their uses go beyond recreational exploring and picking a good place to use your telescope; they can be used by environmental scientists to track wildfires, by economists to estimate GDP of countries, or by intelligence agencies to detect undisclosed industrial facilities.

Can you find any mystery light sources on the map?

Today is the 50th anniversary of the Apollo 11 moon landing. You have probably heard this, because the first moon landing often tops lists of the most significant historical events. It is a cause for celebration of humanity and what we are capable of in the best of times.

Yet many of us ardent space fans have quite mixed feelings about the anniversary, because we have not “been back”. Humanity has not sent a person past low-earth orbit since the end of the Apollo program when Eugene Cernan climbed back into the lunar lander on December 14, 1972.

This is a good time to reflect on our values. It’s not obvious to me that we should have gone to the moon back in 1969. It was ultimately politically motivated, and paid for by taxpayer money. Maybe we should have done something else with that money, like ending the Vietnam war faster. I don’t know. I wasn’t there.

But that was then. What should we do now? We get to decide. NASA is currently pursuing a directive to go back to the moon, as they have been many times since 1972. Their failure to get back has a lot of causes, but a major one is that the populace isn’t rallying for it. Constituents rallied for Apollo for as long as it was a competition with the USSR. After a few half-billion dollar Apollo missions, they started getting tired. They started noticing other problems.

How do you want us to be spending our collective economic fruits? If everyone was a clone of me, then the NFL’s $15 billion revenue would instead be used to double NASA’s budget. But I wouldn’t put everything we have into space exploration; there are too many things that matter. How would you allocate it? And how do you want to be spending your own resources? How much do you want to be exploring the world, going on road trips, discovering new and fascinating people and phenomena, and how much do you just want to make sure that your sister feels better when she gets sick?

As mammals we all have deep drives to conserve and ensure our comfort and survival. As humans, we also have something else; something that helps give meaning to survival. Sometimes, it’s just looking at an object on a shelf and thinking, what is this? You pick it up to inspect it with a look in your eyes. You are not and never were going to buy it. You don’t need to use it for a task. There are another hundred thousand objects in this store. You were just curious.

A bird off in the distance is doing something that catches your eye. It’s circling and dancing around a tree top in a strange way. It periodically lands and takes off again. You watch it for a while, thinking about life as a bird. Is it doing a mating dance? Is it looking for its nest? Is it trying to intimidate some other creature? You’re not going to look it up. You’re not going to film it and ask an ornithologist. You’re just curious. You ask your friends who live nearby. They say they think they’ve seen birds doing that when it gets especially hot and dry. Interesting, you say. The conversation moves on. You’re just curious.

You walk down the street and see someone crouched down, painting a tiny flower on a fire hydrant. They look so happy. Two blocks later, you see someone performing gestures of prayer. They look at peace. When you get back to your apartment, you look at your small garden and smile. You decide to tend to it, and while you do, you think about people. What makes them happy? Why do they do what they do? Why do they find things beautiful? As you garden, you decide that you will start asking people. You gaze down onto the street with a look in your eyes.

Sometimes the curiosity is fleeting, and sometimes it lingers. Sometimes it alerts you to a concern. Sometimes it leads you on a half-day quest to understand, and sometimes it lights a fire inside you, and you acquire an almost paralyzing fixation on the question. You drive your car past your house because you are thinking about the question. You change your careers to better investigate the question. You leave your social support network to move across the country to work with others on the question. You establish an institute and you petition policy makers and you become chief administrator of an entire governmental department to answer the damn question.

I don’t know why we look over horizons and wonder what’s beyond, and I don’t know whether it’s ultimately calibrated toward helping the species survive. I don’t know whether we should have gone to the moon in 1969. But when I think of what we’ve done, I feel a joy that can be fueled no other way, and I would be happy for you to join me on our quest to answer these questions. Let us always take care of ourselves and our loved ones along the way, let us always consider the allocation of resources with utmost somberness, and let us never lose that look in our eyes.

In recent months, two of my hobbies have been amateur telescopy and spectating at orbital rocket launches. Conceptually, these are kin; one brings the universe closer to us, and the other brings us closer to the universe. But experientially, they don’t share much. One is silent, rigid, and tests your patience, the other is an explosion of matter and emotions, gone before you can grasp it.

If there’s anything I’m optimizing for at a launch, it is to “be there”. Everyone knows that rockets go up, just as everyone knows that babies are born. But it is something different to be there. You can watch a live stream of a launch, just as you can watch the superbowl on TV. But even though you see what happens at the same time as everyone else, it is something different to be there.

I don’t know how or why, but some part of the mind knows, and cares deeply, about the distinction between knowing and experiencing. So after I saw my first launch I thought, how can I get closer? How can I increase the intensity of my experience? During that first launch I had used binoculars, and they helped me resolve significantly more detail. So… why not watch a launch through a telescope?

Now, let’s just be clear that this is a ridiculous idea. Finding a still object in the night sky is a tricky endeavor. If it’s really bright like the Mars or Vega you can point and shoot, but for most cases you want a “finder” scope, a smaller, low magnification scope that’s aligned with the big one. It’s far easier to find an object at lower magnification where you can see lots of surrounding context, and then switch to a higher magnification for detail, than to start at higher magnification and only be able to see a few nearby stars for orientation. Furthermore, if the object is moving, it’s tricky to keep up. Most things in the night sky don’t seem to move, but everything has an apparent motion of at least at the rate that the earth rotates. The highest magnification my equipment gets is ~500x, and at that rate the earth takes it out of the viewing field in maybe 15 seconds. I’ve caught planes in the scope before, and it was pretty cool, but you definitely had to be on your toes to keep up with it. Obviously a rocket goes faster than a plane.

Nevertheless, I’m at a place in my life where it’s good for me to practice the virtue of empiricism. So I dragged the gear all the way to Vandenberg and set it up in broad daylight. I was with three other friends and we’re watching a Falcon 9 take up a batch of Iridium satellites. (You can see the original webcast for this launch here). From the closest public viewing spot on Ocean Ave, you can’t actually see the launch facility. Though it’s only 3.5 miles away, the Air Force had an understandable desire that their base not be easily visible, so there’s a hill in the way, just high enough to cover it all. So I couldn’t just point the scope at the rocket on the pad, wait for liftoff, and track it from there. I’d have to catch it in the air.

While we wait, I put in the eyepiece. Normally during an astronomy session, I start looking at something with the lower-magnification eyepieces and work my way up. In this case, my moving target gives me no time to switch them out. I want to see the rocket at the highest magnification I can, but that will also make it harder to find and track in the scope. So I pick an eyepiece in the middle, with a 10mm focal length, giving me 65x magnification. I make sure it’s focused, using the one distant building we can see.

As an aside, I was also curious as to whether the exhaust flames could be seen through the solar viewing glasses we all bought for the eclipse of August 2017. The exhaust has the extraordinary brightness quality of the sun, while being obviously not as bright (otherwise viewing launches would be a discouraged act).

At the exact prescribed time, we see the column of flames rise over the hill, and I grab the eclipse glasses. It takes a second for my eyes to adjust to the darkness (because the launch is during the day) but indeed I can see the flames through the glasses. This puts a very high lower bound on their brightness; much brighter than a lightbulb.

As soon as that’s established, I run over to the scope. With the rocket rising fast, I crouch behind it and slew it to where I think the rocket will be by the time I stand up and get my eye in the eyepiece. Bingo. It’s early enough in the burn that the vehicle still subtends a very large angle in the sky, and its brightness also leaves a halo to follow. But it’s still moving, so I immediately have to get my bearings and start to guide the scope upwards.

The detail is beautiful. I can see the bulb of the payload fairings, I can see the landing legs, I can see the grid fins. If it were rotated correctly, I’m sure I could read the SpaceX logo. I follow its steady rise, up and up and up. I wish I had a camera where my eye is. I lose it for a second, but I follow its orange halo back. Since rockets always end up going away from you, the fuselage tips over and becomes increasingly foreshortened. And since the atmospheric pressure around the rocket is decreasing as it gains altitude, the flames start to fan out. The Falcon 9 has eight engines in a circle and one in the center, making a pattern of flames that ends up looking something like a flower. This pattern is very clear through the scope. The flames spread wider, and consequently get dimmer. After a couple minutes, the flames cut out. There’s no announcer at this viewing spot, so I yell out “main engine cut off!” in case anyone is interested. I see the long white blur split in two, and the pieces drift apart. “Stage separation!” At 50 miles up, the pieces are really tiny, but still discernible. I see flames again. “Second stage ignition!”

Now there are two objects in my view. One of them, carrying the payload, is accelerating toward space under 210,000 pounds of thrust. The other, a charred and spent 16-story machine, is in freefall. I have about four seconds before one of them goes out of view. The booster is landing in the ocean; there’ll be no boost-back burn, but there will be an entry burn to slow it down. The second stage is small and only getting smaller. I decide to let it go.

To my surprise, I see some angular puffs of white come from the top of the first stage. They’re so rapid and dim that they seem more like a light blinking than a rocket engine. I later learn that these are cold nitrogen thrusters, pressurized cans of gas used to make very slow but precise changes to the rocket’s orientation. (You can see these in the webcast starting here.) They appear sporadically, clearly the result of real-time calculations of the rocket’s current position.

Though the booster is now falling to the ground, it’s still travelling away from me and toward the deep pacific ocean. The sheer distance between us gives the sky the chance to obscure it with the blueness of Rayleigh scattering. I lose sight of the now infinitesimal machine.

After almost three minutes of continuous viewing, I step away from the scope and look up for the first time. There’s a fantastic contrail extending to the southeast, and it casts its own shadow in the mist of the upper atmosphere. Besides that, it’s over. There is nothing more to see. Even the crackle has faded. I look around at my friends, realizing that they had a completely different experience than me. That… was awesome. But also… it felt pretty similar to just watching a webcast. It actually felt less like “being there”. After some reflection, I concluded that the fact that I couldn’t easily switch between looking through the scope and looking at the sky, like one can with binoculars, was a critical factor. I could only use one eye. I couldn’t place what I was seeing in my surrounding context; I couldn’t connect it with the sounds I was hearing; I couldn’t see all the people around me reacting. It was worth doing, but I’m very glad I tried it during my second launch viewing. I’ll have to find some other way to get closer.