Author Archive

The Leonids Meteor Shower: A Pre-Turkey Feast for the Eyes

Written by Emily Brodsky

The alarm went off at 3 AM.  I lay on the cabin floor, my breath visible in the cold night air.  The fire, which had been blazing at bedtime, by now had dampened to a few glowing embers.  Imagining the dazzling show that awaited me outside, I resisted the temptation to return to my warm and peaceful slumber.   Instead, I emerged from my puffy cocoon, and tiptoed about the cabin to rouse the adventurous souls who had committed to my pre-dawn wake-up call.  Groggily, we donned our winter coats and hats, and dragged our sleeping bags into the chill of a mid-November night.  We were on a mission to observe one of the universe’s great spectacles: the annual Leonids Meteor Shower.

After stumbling down a dark, wooded path, we planted ourselves in an open field and eagerly fixed our eyes on the sky.  The stars were shrouded by stratus clouds.  We waited.

After half an hour or so, the clouds parted and revealed one of the most awe-inspiring sights I’ve ever witnessed.  For several hours, sparkling streams of light rushed over our heads in all directions.  They varied in color from white to blue to yellow, and I don’t know if I imagined it, but I swore I could hear them zooming through the sky.  The show went on until the meteors were outshined by the light of dawn.  After the final stragglers passed overhead and the darkness began to lift, my friends and I clapped and cheered.  We had witnessed not just a meteor shower, but the great meteor storm of 2001.

Thanksgiving-time brings well-stocked dinner tables, family and friends, and cozy, tryptophan-induced naps.  A less-known fact is that it also brings meteors.  Just before the holiday rolls around each year, one can stumble into the out-of-doors in the dead of night to watch these glittering speed demons as they race across the sky. How do the Leonids put on their marvelous show, and why does it happen with such consistency?

The orbit of the comet Tempel-Tuttle happens to intersect with Earth’s, and when the comet passes by every 33 years it leaves a dense trail of debris.  As the Earth passes through the lingering dust cloud each November, thousands of particles crash into the atmosphere.  These sand grain to pebble sized particles, called meteoroids, travel through space at speeds up to 162,000 miles per hour.  Space is a vacuum, meaning matter is scarce; thus, nothing slows the meteoroids as they speed through the galaxy — that is, until they collide with the matter-laden atmosphere of Earth.

When meteoroids strike, they push up against the gaseous molecules of the atmosphere with incredible force.  The astronomical equivalent of a 10-car pileup occurs, with molecules squishing together in front of each meteoroid, and the resulting pressure generates so much heat that the meteoroids reach boiling point.   The meteoroids continue to move through the atmosphere, vaporizing layer by layer and releasing a tremendous amount of heat.  As the heat releases, the meteoroids and surrounding molecules glow.  From our vantage point 50-75 miles below, these hot, disintegrating particles appear as the streams of light we call meteors, or shooting stars.

The Tempel-Tuttle dust cloud is one of several that Earth passes through consistently.  The predictable display produced by this annual event is called the Leonids because its radiant, or the point from which the meteors appear to radiate, is the constellation Leo.  Other meteor showers include the Geminids in December, the Lyrids in April, and the Perseids in August — their radiants being Gemini, Lyra, and Perseus, respectively.

Although the Leonids have been known to cascade over the sky in numbers up to one-hundred-thousand or more per hour, typical displays are not so prolific.  The last exceptional shows (known as meteor “storms”) were in 2001 and 2002, with meteors-per-hour estimates of up to 3,000.  More commonly, the Leonids shower produces 10-15 meteors per hour.  The numbers depend on a variety of factors, including solar wind and dust cloud density.  Visibility depends on cloud cover and the moon phase.  To see the Leonids in their full splendor, conditions must be just right.

Sadly, the last-quarter moon will be shining near Leo during this year’s November 17-18th peak, resulting in low visibility and a relatively weak show.  Still, I plan to look.  Since that wonderful night in 2001, I have lain in various fields and hiked up mountains to observe the Leonids.  Every year, they seem to be blocked by clouds.  I’ve never been disappointed, however, as the experience of watching celestial events like meteor showers goes beyond the objects themselves; it’s also about the adventure of being outside at an ungodly hour, enduring sleepiness and cold, and sharing an unusual moment with friends.  I encourage you to go out in the wee hours of November 18th; whether you’ll see a shooting star, I cannot guarantee, but I can assure you that the excursion will make you feel alive.

The Sensual Slug

by Danielle Owczarski

During the first cold days of fall in Burlington, I had a chance encounter with a handsome slug on my way to catch the bus. As I hurried past, it glided effortlessly across the moistened slate walkway, its black leopard-print pattern catching my eye. The image of the mysterious figure drifted through my thoughts during the short bus ride to campus.

Limax maximus, also known as the great gray slug and leopard slug. (Photo:© R.J. McDonnell, University of California, Riverside)

Originally, when I thought about writing a blog on the natural history of the great gray slug (Limax maximus), I imagined the story to be a simple, thoughtful, interesting piece; little I knew of the great gray’s sensual secrets. Those of you with weak stomachs or other sensitivities related to natural reproduction may want to surf your way to a blog about cooking or kittens. This story is for those with unquenchable curiosity and a sensible grasp on nature’s sexual exploits.

The great gray is a hermaphrodite. Within its slimy skin layer are organs that support both female and male reproduction. Lucky for the great gray, it is not a simultaneous hermaphrodite like the banana slug, who can self-fertilize. No, the great gray must entice a partner to share in the event of reproductive triumph.

L. maximus, native to Europe, and naturalized in the United States and Australia by way of food transport, leaves a thick string of mucus on the ground in early summer to attract its mate. This activity happens mainly during the night hours for this nocturnal species, who feeds on mushrooms and withered plants.

When its partner detects the secretions, it will follow closely, taking a soft nibble on the tempter’s behind. In a grand chase (at a slug’s speed), the two head for an overhanging feature (a brick wall, tree, or mossy rock). They begin to writhe in what seems a blissful engagement, rubbing and twisting around each other’s lubricated bodies.

As the foreplay advances, they begin to fall gently from their perch, attached only by a dense strand of slime, their pendulous bodies entwined in mid-air. Next, in unison, from an opening (gonopore) on the side of each slug’s head, the penises emerge and begin to entangle. The elaborate spiraling of the white translucent penes forms the shape of a flower similar to that of a blossoming morning glory. The unified form then takes on an azure glow and fertilization ensues. The sperm travels up through the twisted organs, through the gonopores, and inside the slug’s body finally reaching the eggs. The act is complete, both fulfilling their reproductive desires.

It would be biased to leave you with an unspoiled depiction of the great gray’s reproductive story. On some occasions when the entanglement becomes too complex and the slugs are unable to pull apart, apophallation must occur. They chew off one or both penises to relieve the imbroglio and the great gray is left with one working organ to continue its life’s work.

For those of you who can’t get enough, check out David Attenborough’s video clip of the great grays in the act: Limax maximus Reproduction Video.

Natural Destinations: Silvio O. Conte National Fish and Wildlife Refuge

By Danielle Owczarski

A view of Lewis Pond and the Nulhegan River Basin during October foliage.

Far from Burlington, hidden in the low basin of the Nulhegan River in the Northeast Kingdom, awaits a little known National Fish and Wildlife Refuge. The 26,000 acres of refugium established in 1999 encompasses three headwater tributaries to the Nulhegan River, itself a tributary to the 7.2 million acre Connecticut River watershed. Protection of this basin is critical to the health of many species of plants and wildlife and to the water quality of the Connecticut River. The Silvio O. Conte National Fish and Wildlife Refuge was created to protect these valued natural resources.

The North Branch of the Nulhegan River.

Now is the best time to visit the quiet boreal and northern hardwood landscape. Red and sugar maple, balsam fir, tamarack, yellow birch, and beech color the landscape in the fall months, nourishing the soul’s need for creative inspiration. Lewis Pond, the Nulhegan River trail, and Mollie Beattie Bog (named after UVM Alumni and first women director of U.S. Fish and Wildlife), are a few of the Tolkienesque attractions within the refuge. Start your tour at the exemplary Visitor’s Center in Brunswick, VT, to collect trail maps and wildlife viewing guides and explore the interactive interpretive exhibits.

Mollie Beattie Bog, a black spruce woodland bog, is a significant natural community in Vermont. The interpretive trail includes a handicap accessible boardwalk.

The headwaters of the Nulhegan offer a tranquil and wild setting for fly fishermen and women. The Black Branch and North Branch, along with Lewis Pond, comprise healthy brook trout populations, which are periodically stocked by the Vermont Department of Fish and Wildlife. The most recent stocking in the Black Branch on June 20, 2011, included 100 eight-inch yearling brook trout. Studies conducted in 2000 indicate that self-sustaining wild brook trout populations exist within the cool clear tannic waters of the refuge streams. The ideal habitat supports healthy macroinvertebrate populations that provide nourishment for the trout throughout the year.

A wild brook trout caught in the Nulhegan River.

The refuge also supports scientific research studies. While driving or hiking along the refuge roads, lined and filled with gravel and dirt, you’ll come across plots of young low grasses and shrubs, managed to encourage breeding and nesting of the American Woodcock (Scolopax minor). The area is also home to such projects as the Migratory Bird Stopover Habitat Study, the Canada Warbler Study at the Nulhegan Basin Division, Effects of Habitat Fragmentation on Carnivore Distribution and Fitness Indicators in Vermont Forests, and the Study of Public Use on the Nulhegan Basin Division.

Be sure to enjoy the ride.

This land is truly a place for anyone with a passion for the outdoors whether hiking, bird watching, hunting, fishing, observing, or renewing. So turn off the computer, grab a friend, and immerse yourself in Nature.

For directions to and in-depth information about the Silvio O. Conte NFWR:

http://www.fws.gov/r5soc/come_visit/nulhegan_basin_division.html