What Do You See?

For some years I’ve been privileged to be a guest speaker on various cruise ships a few times a year (sponsored onboard as a Smithsonian Speaker), sharing knowledge about astronomy and space science. The trips have been nearly all over the world (although there are still places I haven’t been). They’ve given us a chance to take a peek at some lovely skies and learn together about the universe. It’s a dream job and I enjoy doing it when my sponsors invite me aboard.

One of the most amazing things to me (among many) about doing that job is getting to meet people from nearly all walks of life onboard. And, it’s equally amazing to find out what an interest most people have in “what’s up in the sky”. The world’s space programs have kindled an interest in outer space in many people, and some of my most memorable conversations have been with passengers and crew who have read about a mission or a discovery and want to know more.

I remember once we took a crew member from Bali out to the upper deck who wanted to know the names of some of the southern hemisphere constellations. He had never had the chance to find out what all those different star patterns were. So, we stood out there for quite a while, showing him the Southern Cross, Carina, and then surprising him with a look at one of the Magellanic Clouds, explaining that it was another galaxy. His fascination was palpable, and during the rest of that trip, he brought other crew members to me to ask their questions about the sky.

On that same voyage, a few nights later, we were having a star party on the top deck (open to all), and I got into a fascinating conversation about ancient astronomy with a rabbi from Jerusalem. We were joined by one of the officers, a young woman from Holland, who told us that her father had been an amateur astronomer for many years, and that he taught her about stargazing and navigation before she went to sea.

One day on a ship in the Mediterranean, I was giving a talk about exploring the Moon and Mars, and I had a guy ask me how to calculate an orbit around the Moon. I began to explain from first principles how you do the calculations, and he waved his hand again and said, “What about mascons?” I looked at him in amazement, and he finally stood up and told us that he used to work on the Apollo missions. One of his jobs was to calculate orbits for the mission and that mascons were a big part of the calculation. Turns out he was on a cruise reunion of others who worked on the same missions.

I’ve since had many experiences like that, showing me that there is an abiding interest in the sky that all of us share. In essence, we share the sky, and the sky (and its exploration) is and always be part of our history.

A lot of people, when they find out that we do star parties at sea assume that the skies must always be stunning, out away from the cities and towns. It’s true that the skies are stunning, but we don’t always get to see them. Weather plays a big role, and many a night we’ve planned a star party only to find out that it’s raining, or too windy to go out. Sometimes the weather is fine, but the humidity or “surface clutter” futzes up our viewing. If we happen to be cruising along at a good clip, the ship itself throws mist into the air, and that affects our seeing, too. On some nights, only the brightest stars and planets shine through.

Another factor is safety. All passenger ships have lighted railings so that passengers may find their way safely around the decks at night. Some ships have very bright strings of lights up top, and a few have giant movie screens that you can see for miles. The result is less-than-desirable conditions for stargazing. On some ships, I can ask for lights out, and, subject to the captain’s judgment, we can get permission for a dark area on the top deck for perhaps an hour. But, safety concerns rule everything we do, and sometimes we just make do with the conditions we have. One one cruise I was actually a full crew member (required by the country we were heading to—I could be a passenger or I could be crew, so they made me crew) and I had a short course in Safety of Life at Sea (SOLAS), and those safety reasons were drilled into us in the class. So, I understand when the captain does not give permission for lights out, and we do the best we can.

That being said, there is NOTHING like a dark sky at night at sea when you can experience it. To paraphrase Roy Batty in Blade Runner, “I’ve seen things you people wouldn’t believe…”  such as the Magellanic Clouds nearly overhead (which, for northern hemisphere dwellers is a distinct treat), star clusters in the southern Milky Way, the faint glow of the aurora australis off the coast of South America, the Pleiades rising in the early morning one late autumn night in the Mediterranean, and many other cool cosmic delights.

When you’re out at sea watching the stars, you’re taking part in an activity that goes back to the earliest humans who explored the planet. Somewhere in our distant past, we learned to use the sky as a wayfaring guide, a navigational map. We figured out the season from watching the sky, and from that knowledge, we learned to live and thrive. There is much truth to what Carl Sagan said: that we are the descendants of astronomers. You don’t need to go to sea to get that feeling—stargazing for a long period from any dark sky site will give it to you, too. But, I never felt it more keenly than when I was onboard a ship in the Mediterranean, off the coasts of Israel and Egypt, looking at the same stars the earliest people who lived in those areas saw,  who used their observations of the sky to formulate many of the precepts that underlie what we know about the stars, planets, and galaxies today.

So, what do you see when you stargaze from a ship? Stars, of course. But also, the things that taught our ancestors how to travel and explore. They and the stars gave us a mighty legacy.  I’m glad we still explore today.