Archives For July 2015

Photo: Image showing granular structure of the Sun's photosphere. Photo by James Guilford, Stephens Memorial Observatory.

Granular Sun – July 20, 2015

Testing out a modified eyepiece adapter today, I had the vintage Cooley Telescope pointed at the Sun. Since everything was set up, I decided to see whether we could capture decent images of our nearest star, near noon on this clear summer day. While the sky was clear, the seeing — quality of the view — was not as good as I’d hoped. Apparently, midday heat was causing the image to “shimmer” in the eyepiece and the photographs reflected that. Examining the pictures on the computer screen, I was disappointed because I saw no details in the several sunspots visible. As I made some photographic adjustments, however, other features came into view: granulation and faculae! The granules, upwelling super-hot cells of solar atmosphere, are easy to see; they give the image above a “grainy” appearance. Faculae are a bit trickier but if you look along the darker right-hand edge of the solar image, you will see some light-colored patches — those patches are faculae! So a bit of disappointment changed to a sunny day surprise.

NOTES: Sunspots in this image are #2387 (L) and #2386 (R). For more information on the Sun’s photosphere and what can be seen there, visit this page at NASA/ Marshall Space Flight Center.

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Stephens Memorial Observatory of Hiram College will be open to the public on Saturday, July 25, from 9:30 to 11:00 PM. On the observing list for the night are: the Moon, ringed world Saturn, and star cluster M4 in Scorpius.

No reservations are required and there is no admission fee for observatory public nights. Cloudy skies at the starting time cancel the event and, in that case, the observatory will not open.

The Observatory is located on Wakefield Road (Rt. 82) less than a quarter of a mile west of Route 700 in Hiram. There is no parking at the Observatory. Visitors may park on permissible side streets near the Post Office, a short distance east of the observatory.

Pluto, at last!

StephensAstro —  July 14, 2015 — Leave a comment
Photo: Pluto as imaged by NASA's New Horizons spacecraft on July 13, 2015.

Portrait of a Mysterious World – Credits: NASA/APL/SwRI

Pluto nearly fills the frame in this image from the Long Range Reconnaissance Imager (LORRI) aboard NASA’s New Horizons spacecraft, taken on July 13, 2015 when the spacecraft was 476,000 miles (768,000 kilometers) from the surface. This is the last and most detailed image sent to Earth before the spacecraft’s closest approach to Pluto on July 14. The color image has been combined with lower-resolution color information from the Ralph instrument that was acquired earlier on July 13. This view is dominated by the large, bright feature informally named the “heart,” which measures approximately 1,000 miles (1,600 kilometers) across. The heart borders darker equatorial terrains, and the mottled terrain to its east (right) are complex. However, even at this resolution, much of the heart’s interior appears remarkably featureless — possibly a sign of ongoing geologic processes.

After a decade-long journey through our solar system, New Horizons made its closest approach to Pluto Tuesday, about 7,750 miles above the surface making it the first-ever space mission to explore a world so far from Earth. The three-billion-mile journey took about one minute less than predicted when the craft was launched in January 2006. The spacecraft threaded the needle through a 36-by-57 mile (60 by 90 kilometers) window in space — the equivalent of a commercial airliner arriving no more off target than the width of a tennis ball.

Photo: Clyde Tombaugh

Clyde Tombaugh

The Pluto story began only a generation ago when young Clyde Tombaugh was tasked to look for Planet X, theorized to exist beyond the orbit of Neptune. He discovered a faint point of light that we now see as a complex and fascinating world. As a tribute to Tombaugh, who died in 1997 at age 90, a tiny canister of his ashes was placed inside the New Horizons spacecraft.

“Pluto was discovered just 85 years ago by a farmer’s son from Kansas, inspired by a visionary from Boston, using a telescope in Flagstaff, Arizona,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington. “Today, science takes a great leap observing the Pluto system up close and flying into a new frontier that will help us better understand the origins of the solar system.”

New Horizons’ flyby of the dwarf planet and its five known moons is providing an up-close introduction to the solar system’s Kuiper Belt, an outer region populated by icy objects ranging in size from boulders to dwarf planets. Kuiper Belt objects, such as Pluto, preserve evidence about the early formation of the solar system.