Category Archives: astronomy

Citizen Astronomy

It’s a Tradition to Carry Forward

Suddenly citizen journalism is a big thing on news sites. They want YOU to go out and film events happening and then “share” them with other viewers/readers. I think it’s kind of an interesting twist on the traditional journalistic practice of having reporters actually covering events and interviewing people on the scene.

In astronomy, we’ve had “citizen observers” since the dawn of time.  These days it’s called “amateur astronomy” and there are hundreds of thousands of people who devote some part of their time each week watching the sky, looking at the stars, and in some cases, discovering new things along with the “professionals.”

Amateur astronomy has a star-studded history (so to speak).  Back before Big Astronomy got Big Budgets to build Big Instruments (say, prior to the late 1800s and early 1900s), there was little practical difference between amateur and professional stargazers.  For a time, it was a rich man’s profession because wealthy folks had the shiny gold rocks to trade for building big telescopes.  But, things have changed since then, and while we have two divisions of astronomers these days — the ones who love what they do and get paid for it (and work with equipment paid for with taxpayer dollars/yen/yuan/Euros, etc.) vs. the ones who love what they do and do it for free — in some places, amateurs and professionals work together to make discoveries.  In fact, in many studies, professionals depend on amateurs to gather data. Some that come to mind are the American Association of Variable Star Observers (which is actually an international group) Center for Backyard Astrophysics, the International Occultation Timing Association, and others you can read about here.

For folks who aren’t interested in going the research route, even as an amateur, the International Year of Astronomy has a number of “citizen-oriented” activities planned, including a massive observation of the star Epsilon Aurigae in summer 2009, Globe at Night, Astronomy 2009 in Second Life, 365 Days of Astronomy, the Galileoscope and the Galileo Teacher Training Program, and many, many others. And, after you do all these things, you can get online and blog about your experiences or even publish videos of you and your friends and family doing stargazing and space science activities. That combines the best of both worlds: citizen journalism and citizen astronomy!

Musings on Miranda

Cat Moon

Miranda Katt
Miranda Katt

We have a cat named Miranda. As you can see, she’s got a mottled coat, with no two areas exactly the same shape and with an underlying “white” coat overlain by other regions of different-colored hair.

When we got her, we were casting about for a name and I happened to be looking at pictures of the moon Miranda. It occurred to me that, like that moon, our cat had white “surface units” overlaid by other mottled, oddly shaped surface units.

Miranda (the cat) came by her mottled “surface” through a combination of genetic factors inherited from both her parents.

She’s a calico cat, in much the same way that you can think of Miranda the moon as a calico moon, marked with oddly shaped regions and different colors for each of the regions.

The Uranian moon Miranda
The Uranian moon Miranda

The “genetic” components that shaped the surface of Miranda (the moon) have more to do with physical processes like gravitation and the melting point of water ice.

The scientific consensus is that this moon, with its icy grooves and cliffs, has been deformed by a process called tidal heating.  What this means is that Miranda, which is largely water ice, was affected by tidal forces from Uranus early in this moon’s history. The gravitational tugs from Uranus deformed the moon slightly, causing some interior heating.  That heat melted the ice inside of Miranda, and chunks of it likely “floated” to the surface and then froze. That process (which is complex) caused the wrinkles and ridges, troughs and gullies we see today.  No cat fur, but still a mottled, calico surface on a distant moon!