[FOTZeiss] Fw: Neptune Completes 1st Solar Orbit Since Discovery

[Glenn A. Walsh]

FYI

Neptune Completes Its First Circuit Around The Sun Since Its Discovery
at precisely: Tuesday, 2011 July 12, 6:27 p.m. EDST.

More information in the forwarded message, following the signature:

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://friendsofthezeiss.org >
Electronic Mail - < siderostat1989 at yahoo.com >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
  < http://buhlplanetarium.tripod.com/#news >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh: 
  < http://buhlplanetarium.tripod.com >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries: 
  < http://andrewcarnegie.tripod.com >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh: 
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >


--- On Tue, 7/12/11, Ron Baalke <baalke at ZAGAMI.JPL.NASA.GOV> wrote:

> From: Ron Baalke <baalke at ZAGAMI.JPL.NASA.GOV>
> Subject: Neptune Completes Its First Circuit Around The Sun Since Its Discovery
> To: HASTRO-L at listserv.wvu.edu
> Date: Tuesday, July 12, 2011, 3:11 PM
> July 12, 2011
> 
> ** Contact info appears below. **
> 
> Text:
> http://heritage.stsci.edu/2011/19/caption.html
> 
> Images:
> http://hubblesite.org/news/2011/19
> http://heritage.stsci.edu/2011/19
> 
> NEPTUNE COMPLETES ITS FIRST CIRCUIT AROUND THE SUN SINCE
> ITS DISCOVERY
> 
> Today, Neptune has arrived at the same location in space
> where it was
> discovered nearly 165 years ago. To commemorate the event,
> NASA's
> Hubble Space Telescope has taken these "anniversary
> pictures" of the
> blue-green giant planet.
> 
> Neptune is the most distant major planet in our solar
> system. German
> astronomer Johann Galle discovered the planet on September
> 23, 1846.
> At the time, the discovery doubled the size of the known
> solar system.
> The planet is 2.8 billion miles (4.5 billion kilometers)
> from the Sun,
> 30 times farther than Earth. Under the Sun's weak pull at
> that
> distance, Neptune plods along in its huge orbit, slowly
> completing one
> revolution approximately every 165 years.
> 
> These four Hubble images of Neptune were taken with the
> Wide Field
> Camera 3 on June 25-26, during the planet's 16-hour
> rotation. The
> snapshots were taken at roughly four-hour intervals,
> offering a full
> view of the planet. The images reveal high-altitude clouds
> in the
> northern and southern hemispheres. The clouds are composed
> of methane
> ice crystals.
> 
> The giant planet experiences seasons just as Earth does,
> because it is
> tilted 29 degrees, similar to Earth's 23-degree tilt.
> Instead of
> lasting a few months, each of Neptune's seasons continues
> for about 40
> years.
> 
> The snapshots show that Neptune has more clouds than a few
> years ago,
> when most of the clouds were in the southern hemisphere.
> These Hubble
> views reveal that the cloud activity is shifting to the
> northern
> hemisphere. It is early summer in the southern hemisphere
> and winter
> in the northern hemisphere.
> 
> In the Hubble images, absorption of red light by methane in
> Neptune's
> atmosphere gives the planet its distinctive aqua color. The
> clouds are
> tinted pink because they are reflecting near-infrared
> light.
> 
> A faint, dark band near the bottom of the southern
> hemisphere is
> probably caused by a decrease in the hazes in the
> atmosphere that
> scatter blue light. The band was imaged by NASA's Voyager 2
> spacecraft
> in 1989, and may be tied to circumpolar circulation created
> by
> high-velocity winds in that region.
> 
> The temperature difference between Neptune's strong
> internal heat
> source and its frigid cloud tops, about minus 260 degrees
> Fahrenheit,
> might trigger instabilities in the atmosphere that drive
> large-scale
> weather changes.
> 
> Neptune has an intriguing history. It was Uranus that led
> astronomers
> to Neptune. Uranus, the seventh planet from the Sun, is
> Neptune's
> inner neighbor. British astronomer Sir William Herschel and
> his sister
> Caroline found Uranus in 1781, 55 years before Neptune was
> spotted.
> Shortly after the discovery, Herschel noticed that the
> orbit of Uranus
> did not match the predictions of Newton's theory of
> gravity. Studying
> Uranus in 1821, French astronomer Alexis Bouvard speculated
> that
> another planet was tugging on the giant planet, altering
> its motion.
> 
> Twenty years later, Urbain Le Verrier of France and John
> Couch Adams
> of England, who were mathematicians and astronomers,
> independently
> predicted the location of the mystery planet by measuring
> how the
> gravity of a hypothetical unseen object could affect
> Uranus's path. Le
> Verrier sent a note describing his predicted location of
> the new
> planet to the German astronomer Johann Gottfried Galle at
> the Berlin
> Observatory. Over the course of two nights in 1846, Galle
> found and
> identified Neptune as a planet, less than a degree from Le
> Verrier's
> predicted position. The discovery was hailed as a major
> success for
> Newton's theory of gravity and the understanding of the
> universe.
> 
> Galle was not the first to see Neptune. In December 1612,
> while
> observing Jupiter and its moons with his handmade
> telescope,
> astronomer Galileo Galilei recorded Neptune in his
> notebook, but as a
> star. More than a month later, in January 1613, he noted
> that the
> "star" appeared to have moved relative to other stars. But
> Galileo
> never identified Neptune as a planet, and apparently did
> not follow up
> those observations, so he failed to be credited with the
> discovery.
> 
> Neptune is not visible to the naked eye, but may be seen in
> binoculars
> or a small telescope. It can be found in the constellation
> Aquarius,
> close to the boundary with Capricorn.
> 
> Neptune-mass planets orbiting other stars may be common in
> our Milky
> Way galaxy. NASA's Kepler mission, launched in 2009 to hunt
> for
> Earth-size planets, is finding increasingly smaller
> extrasolar
> planets, including many the size of Neptune.
> 
>                
>            # # #
> 
> Credit:
> NASA, ESA, and the Hubble Heritage Team (STScI/AURA)
> 
> Image files, video, and more information about Neptune:
> http://hubblesite.org/news/2011/19
> http://heritage.stsci.edu/2011/19
> http://www.nasa.gov/hubble
> 
> Media Contacts:
> Donna Weaver / Ray Villard
> Space Telescope Science Institute, Baltimore, Md.
> +1 410-338-4493 / +1 410-338-4514
> dweaver at stsci.edu
> / villard at stsci.edu
> 
> Science Contact:
> Keith Noll
> Space Telescope Science Institute, Baltimore, Md.
> +1 410-338-1828
> noll at stsci.edu
> 
> Hubble is a project of international cooperation between
> NASA and the
> European Space Agency. Goddard manages the telescope. The
> Space
> Telescope Science Institute (STScI) conducts Hubble
> science
> operations. STScI is operated for NASA by the Association
> of
> Universities for Research in Astronomy Inc. in Washington.
>