Tag: observatory

Part 1

Posted on by Brian Garthwaite
Ditto of Math 101 final exam, part 1, from November 15, 1948
Ditto!

Astronomy, here and elsewhere often under the Physics umbrella, was once part of the Mathematics department at Bucknell. Occasionally, we’ll stumble across some old files in the Observatory that have been yellowing gracefully for decades. Like this two-part final exam from Math 101. Algebra!

Of note for context: this old exam – November 15th, 1948 – waited patiently in a filing cabinet at the current Observatory, built in 1963. In all likelihood, it sat in a folder in the old Observatory for thirteen years, transferred to Tustin Gym for a time, and then quietly continued to be forgotten in a new building until some tech decided to clean the place up a bit.

Who doesn’t love finding curiosities in purple ditto ink?

Stamped

Posted on by Brian Garthwaite
Lead brick, painted yellow, stamped by Nuclear Associates of Carle Place, NY.
It’s big, heavy, and boldly colored.

Lead bricks are useful things. This one – still bearing the stamp of Nuclear Associates, of Carle Place, NY – has had its fair share of scuffs and dents. (Lead’s soft stuff, you know.) These days it functions as a handy doorstop and a hands-on tool for explaining the density of matter.

Denser than water, than aluminum, than a nickel-iron meteorite. (All easy samples to acquire for demonstration.) Less dense than osmium; about half as much. (Not on hand, unfortunately.) Definitely less dense than the core of our Sun, by an order of magnitude-plus.

Also no handy samples of stellar core plasma on hand.

Leonids

Posted on by Brian Garthwaite
Meteor counting log, Leonids shower, from November 1934
Up to three per minute!

Ninety years ago, during the Leonids meteor shower, someone was counting a lot of burning bits of debris from comet 55P/Tempel-Tuttle. With one fifteen-minute window boasting forty-five meteors (!), that’s a powerfully active shower. Not quite a storm, but those happen with the Leonids sometimes.

According to NASA, the Leonids peak about every 33 years, with 1966 being a spectacular meteor storm. In one fifteen-minute window, thousands of meteors fell like glowing rain. How amazing is that?

Also: check out the times indicated. We’re assuming the counting started at 11:00pm and ran until early morning, with a 24-hour clock opposite how we’d expect it. (Maybe sleep deprivation?) Either that or it was a truly spectacular meteor shower!

Radio Telescope Repair

Posted on by Brian Garthwaite
Radio telescope nose with cracked plastic structure
Proceed with caution.

After enough years of outdoor UV exposure, temperature fluctuations, and who knows what all else, most plastics start to break down. The thin support ring – looks like polyethylene of some sort – has started to crumble, and the radio telescope’s nose cone is hanging loosely.

Interior electronics of radio telescope.
Still working!

Inside, the receiver and amplifier appear to be in good enough shape. Note that many birds and many bugs have made a real mess of things.

Bird's nest filling nose cone.
Not suitable for single-stream recycling.

And they’ve built an astounding nest inside. Dried grass, last year’s hydrangea blooms, torn bits of plastic bags, some shredded paper, a few ripped-up bits of surgical masks. Removing all of this did not endear us to the starlings.

Machined aluminum brackets with screws
Measure twice, mill once.

The plastic solution worked for a while, but it’s time to up our game. Aluminum brackets, precisely machined out of solid blocks, drilled and tapped for stainless steel hardware. Bright and shiny and destined to be hidden away from view.

Radio telescope with restored nose cone, gaps sealed with duct tape.
Duct tape buys time.

And then, with summery Pennsylvania weather on the horizon (read: thunderstorms), we seal the whole mess up with duct tape. Maybe it’ll deter the birds until we can deal with the rest of it some fall.

The most amazing part is that we didn’t end up using hot glue.

Construction Photo

Posted on by Brian Garthwaite
Aerial photograph of the Observatory construction, 1963
1963: a quiet corner of campus.

Six decades ago, there wasn’t much on the south end of campus, making it an ideal place for the new Observatory. Relatively calm, not much to block the view, and few sources of nearby light pollution. A lot can change in that time.

Today’s maples and oaks – not pictured, because they were maybe saplings? – are now large enough that they block some low areas of observation and are losing limbs due to disease and age. The stadium has been wreathed by parking lots and festooned with high-intensity lights. Campus buildings have crept southward, surrounding the site. Lewisburg and its surroundings have developed, installed more nighttime lighting, and the sky has grown brighter, obscuring more of the night sky.

Clouds, however: they’re here as much as they ever were. Oh, central Pennsylvania.

Wind Speed Indicator

Posted on by Brian Garthwaite
Wind speed indicator with wind chill chart
Must get real cold at some weather stations.

This particular wind speed indicator hasn’t been functional in ages, but at some point it was probably useful in determining whether or not to go outside for telescope observations. Wind is of concern in astronomy, as it can produce poor seeing and – when really strong – cause telescopes to shake. But wind chill is the more immediate concern. Cold nights can be good for observing, with clear skies and good seeing, but rough on fingers and toes.

All of that standing still, lack of warming sunshine, etc. doesn’t do a lot to counter a cold night. Maybe think ahead and bring along a hot beverage?

An awful lot of that chart is devoted to conditions when no one should be outside at all. One line of thought considers that a chart with all of your category indicators bunched up on the left isn’t the ideal for communicating information visually. Another notes that an endless tundra of negative numbers tells you enough without needing the particulars.