September 2014

Treasurer's report:

Beginning balance August 1 $1511.33

Less New Hampshire Ins. Co. liability insurance $320.00

Ending balance August 31 $1191.33

October meeting:

Elect officers for coming year

Program otherwise TBD

Astronomy news—Daryl:

Rosetta mission to Comet 67P: Launched March 2004, Rendezvous May 2014, end of mission Dec. 2015. Landing site on 67P in process of being determined.

Supermoons:

July 12, August 10 (even bigger than July), September 8 (a bit smaller than in August)

Sunspots:

Good ones Sept. 9, in the last 4-5 days of a solar flare

Astronomy star party:

Held August 23 E. of high school. Saw Saturn rings and Lagoon Nebula

And that morning, 1 hr before sunrise, waning moon and Jupiter and Venus were in a pretty triangle

Early morning hours now: Good view of Jupiter, Orion, Gemini

John Grismore—presentation on trip to McDonald Observatory and VLA array in New Mexico

The VLA:

On “our” highway 60 (it crosses it!)

Is arranged in 3 arms with 27 antennae total, nine in each arm

Each antenna is independent of the other

Disk diameter of each is 82 ft

Height of each is 94 ft

Weight of each is 230 tons

Antennae can be configured 4 different ways

Maximum aperture is 22 miles

Minimum resolution is .05 arcseconds

Frequency is 74 mHz-60 gHz

VLA was built in 1973-1980 and upgraded in 2010

Train tracks are used to move the antennae.

By 2000, over 10,000 projects had been worked by the VLA by 2200 researchers. The VLA has played a key part in the discovery of ice on the poles of Mercury, micro-quasars in the Milky Way, the first Einstein ring, and precise locations of Gamma ray bursts.

The VLA synthesizes 27 images into one.

McDonald observatory:

Built in the 1930’s

Has a very nice visitor’s center

They encourage night star parties and offer daytime tours of telescopes

If you want to book into a session, plan to do so 6 months to a year ahead

They have a visitor’s amphitheater to view nighttime constellations.

They have 16 inch, 22 inch and 36 inch telescopes

They have a Star Date publication, a radio show and podcast

They have workshops for K-12 teachers

They are now funded by UT; in the 1930s were funded by a Texas banker

They worked with the University of Chicago in the 1930s

They have a dedicated solar telescope

The observatory’s Harlan J Smith telescope’s primary mirror is 107 inches in diameter and weighs 7800 pounds. The telescope tube diameter is 12 ft and length is 32 ft. It weighs overall 16 tons.

The observatory has—

Measured the earth-to-moon distance

Helped develop technology for the Hubble telescope

Helped develop high speed photometry

Helped develop stellar and galactic spectroscopy

The observatory’s Hobby-Eberly site and dome is always 55 degrees above the horizon and is the 5th largest in the world. Has 91 separate hexagonal mirrors and is 30 feet in diameter with full 360-degree azimuth. It has been involved in exoplanet discoveries, supernovae observations, galactic rotations and dark energy research.