Monday, July 25, 2016

NASA Time-Lapse Video From Space: Sunlit Earth Over One Year

DSCOVR location in relation to the Earth and sun / Image courtesy of NOAA
Location of the DSCOVR satellite, in relation to the Earth and Sun, known as
Lagrange Point 1 (L1).
(Graphic Source: National Oceanic and Atmospheric Administration)

By Glenn A. Walsh
Reporting for SpaceWatchtower

On YouTube, NASA has released a time-lapse video (2 minutes, 46 seconds in length), taken from a distance of one million miles from the Earth, showing the Earth over a period of one year. More than 3,000 color photographs, taken at least once every two hours beginning on 2015 July 6, show several events (including a Solar Eclipse and Lunar Transits) that occurred on the sunlit side of our planet while rotating on its axis 366 times.

These photographs were taken by the EPIC (Earth Polychromatic Imaging Camera) camera on the DSCOVR (Deep Space Climate Observatory) satellite, sponsored by the National Oceanic and Atmospheric Administration (NOAA). This satellite is in orbit of the Earth, about a million miles away from our planet, at the spot in space known as Lagrange Point 1.

Lagrange Point 1 (L1) is one of five Lagrange Points in relation to three bodies in space. In this case, L1 is the point in space where the gravity of the Earth, gravity of the Sun, and, also, the Apparent Centrifugal Force of a third body (DSCOVR satellite) are in a rough equilibrium This allows the satellite, located in such a position, to remain in orbit around the Earth using a minimum of fuel, and to always remain directly between the Sun and the Earth.

The five Lagrange Points are named for 18th century mathematician Joseph-Louis Lagrange, who wrote about these points in a 1772 paper regarding, what he called, the “three-body problem.”

EPIC takes images of ten different wavelengths. Then, three of these wavelengths, correlated to the colors red, green, and blue, are combined to provide a realistic, color image of what the viewer would see, if the viewer was on the satellite.

This video shows moving cloud and weather patterns and large storms, along with continents and oceans quickly passing along on the surface as each day passes. Good views of the North Pole and the South Pole are seen in the video, during their respective Summer seasons (when the respective Pole is tilted towards the Sun, and hence, also tilted towards the satellite).

The EPIC camera caught the Moon's shadow move across the Earth's surface during the 2016 March 8 - 9  Total Solar Eclipse, which was visible from parts of Indonesia and the Pacific Ocean. Additionally, since this satellite is four times farther from the Earth than is Earth's Moon, the EPIC camera viewed the Moon transit, or move across the Earth's disk, a couple of times during this year of observation (2015 July 16 and 2016 July 4).

As this satellite is “parked” at L1, it could view both the Sun and the sunlit Earth 24 hours a day. The DSCOVR satellite, operated by NOAA, is an Earth observation satellite which could help weather forecasting for NOAA's National Weather Service (NWS). Another satellite located at L1, SOHO (Solar and Heliospheric Observatory), continually watches and studies the Sun.

As an Earth observation satellite, DSCOVR and the EPIC camera are tasked with watching Earth's weather patterns, as well as measuring ozone and aerosol in the atmosphere, the type and height of clouds, vegetation on Earth's land masses, hotspots on the planet, and making estimates of Ultraviolet (UV) radiation on the Earth's surface. This is the first time we are receiving continual images of our planet from this great a distance. The DSCOVR satellite is expected to last at least five years.

NASA Time-Lapse Video: Link >>> https://www.youtube.com/watch?v=CFrP6QfbC2g

Internet Links to Additional Information ---

More on the DSCOVR satellite:
Link >>> https://en.wikipedia.org/wiki/Deep_Space_Climate_Observatory

More on the EPIC camera:
Link >>> https://en.wikipedia.org/wiki/Deep_Space_Climate_Observatory#EPIC

More on Lagrange Points:
Link 1 >>> http://www.haydenplanetarium.org/tyson/read/2002/04/01/the-five-points-of-lagrange
Link 2 >>> https://en.wikipedia.org/wiki/Lagrangian_point

More on Apparent Centrifugal Force and Centripetal Force:
Link 1 >>> http://phun.physics.virginia.edu/topics/centrifugal.html
Link 2 >>> http://sydney1206.blogspot.com/2013/05/centripetal-force.html
Link 3 >>> http://www.livescience.com/52488-centrifugal-centripetal-forces.html

More on NOAA:
Link >>> https://en.wikipedia.org/wiki/National_Oceanic_and_Atmospheric_Administration

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2016 July 25.


                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

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Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >

Monday, July 18, 2016

New, Large Asteroid Found in Outer Solar System


Slow-motion of image of newly-
discovered Asteroid 2015 RR245,
in the Outer Solar System.
(Image Source: Outer Solar System Origins
Survey Team)

By Glenn A. Walsh
Reporting for SpaceWatchtower

A new, large asteroid has been found in the Kuiper Belt of the Outer Solar System. In fact due to the current size estimates of the Asteroid / Minor Planet named 2015 RR245, some scientists wonder if it should be designated as a Dwarf Planet.

Although first spotted last September 9 (hence, the 2015 designation), it was not until subsequent observations of the object in February and June when astronomers concluded that 2015 RR245 was a large asteroid. It was first spotted by J.J. Kavelaars of the National Research Council of Canada, using the Canada-France-Hawaii Telescope on top of Mauna Kea in Hawaii.

These observations were part of the four-year Outer Solar System Origins Survey (OSSOS), which started in February of 2013. Involving more than 40 scientists at institutes in 8 countries, this international collaboration seeks to discover distant moving objects in the Outer Solar System, which may allow the scientists to test models regarding how our Solar System evolved.

Using follow-up images of this asteroid in February and June, taken by Michele Bannister of the University of Victoria, more specific estimates of the object were derived. The “year” of 2015 RR245 (i.e. the time it takes to make one revolution around the Sun) is 730 Earth years.

The eccentric orbit of this asteroid takes it to a maximum distance from the Sun of 11.9 billion miles / 19.2 billion kilometers. However, the current location of 2015 RR245 in its orbit means the object is now approaching the Sun (possibly, one of the reasons we now found this object). At its closest, the orbit will bring 2015 RR245 as close as 3.1 billion miles / 5 billion kilometers to the Sun in the year 2096. Currently, this Kuiper Belt object is about 5.9 billion miles / 9.5 billion kilometers from the Sun.

The size of the object is more indefinite. With an apparent visual magnitude in the Mauna Kea telescope of 22, it may be as large as 450 miles / 700 kilometers across. This estimate goes on the assumption that the object's surface is only reflecting 10 per-cent of sunlight.

However, if the object's surface has a lot of ice, it may be reflecting as much as 25 per-cent of sunlight. Hence, such a brighter object may only be about 279 miles / 450 kilometers across.

The size of the object is one determinant of its eligibility to be considered a Dwarf Planet. Thus far, the International Astronomical Union (IAU) has designated, officially, only 5 Dwarf Planets: Asteroid Ceres, Pluto, and three other (besides Pluto) objects beyond the orbit of Neptune (known as Trans-Neptune objects): Eris, Haumea, and Makemake. A sixth Trans-Neptune object, 2007 OR10, is considered large enough to someday be designated as a Dwarf Planet.

Although no other, official, Dwarf Planets have been designated, thus far, the IAU criteria for such designations means that several more Trans-Neptune objects may qualify. And, 2015 RR245 may eventually be one of them.

The IAU's Minor Planet Center, which operates at the Smithsonian Astrophysical Observatory along with the Harvard College Observatory in Cambridge, Massachusetts, has catalogued 1,491 Trans-Neptune objects, as well as another 501 objects with odd, very elliptical orbits in the Outer Solar System. With continuing astronomical observations of the Outer Solar System, they usually find a new Trans-Neptune object every week! However, most of these objects are much, much smaller than 2015 RR245.

Internet Links to Additional Information ---

Canada-France-Hawaii Telescope Announcement of Discovery of 2015 RR245:
Link >>> http://cfht.hawaii.edu/en/news/NewDwarfPlanet/

More details regarding 2015 RR245 - Minor Planet Electronic Circular 2016-N67:
Link >>> http://www.minorplanetcenter.net/mpec/K16/K16N67.html

More on the Outer Solar System Origins Survey: Link >>> http://www.ossos-survey.org/

More on the Canada-France-Hawaii Telescope:
Link >>> https://en.wikipedia.org/wiki/Canada%E2%80%93France%E2%80%93Hawaii_Telescope

More on the Kuiper Belt: Link >>> https://en.wikipedia.org/wiki/Kuiper_belt

More on Dwarf Planets: Link >>> https://en.wikipedia.org/wiki/Dwarf_planet

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2016 July 18.


                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >

Monday, July 11, 2016

Leap-Year to be Even Longer w/ Added Leap-Second!


Time display of the last Leap-Second, from the < www.time.gov >
Internet web site of the National Institute of Standards and Technology,
U.S. Department of Commerce. This time was Coordinated Universal
Time (UTC), which translated to 7:59:60 p.m. Eastern Daylight Saving
Time (EDT) on 2015 June 30.
(Image Sources: Wikipedia.org , By US Government / NIST - Screen Grab from web
display of www.time.gov, Public Domain, https://commons.wikimedia.org/w/index.
php?curid=41453932 )

By Glenn A. Walsh
Reporting for SpaceWatchtower

Every four years (usually), the calendar year is longer by 24 hours, than the previous three years. However this Leap-Year of 2016 will be even longer, by one second, with the addition of a Leap-Second at the end of the year.

On July 6, the U.S. Naval Observatory announced that a Leap-Second would be added to the civil time scale on the evening of 2016 December 31 at 23:59:60 Coordinated Universal Time (UTC) / 6:59:60 p.m. Eastern Standard Time (EST). Leap-Seconds are added, occasionally when needed, at either the end of June or the end of December, or both.

Since the first Leap-Second was added in June of 1972, 26 Leap-Seconds have been added over the years. Leap-Seconds added in both June and December of the same year have occurred only once, thus far: in 1972, the year Leap-Seconds commenced. The last Leap-Second was added on 2015 June 30 at 23:59:60 UTC / 7:59:60 p.m. Eastern Daylight Saving Time (EDT).

Leap-Seconds have been added, periodically, to respond to the continual slowing of the rotation rate of the Earth, so the world's clocks do not vary significantly from the normal sunrise and sunset times throughout the year. Tidal forces from the Moon (and to a lesser extent, the Sun), in addition to the well-known ocean tides, work to slow the Earth's rotation rate. Geologic conditions that change the distribution of the Earth's mass, such as the movement of the Earth's crust relative to its core, are a contributing factor to slowing of the rotation rate.

In theory, a negative Leap-Second, retracting one second at the end of June or December, is also possible. This would occur if the Earth's rotation rate started accelerating. However, there has never been a need for a negative Leap-Second.

The slowing of the Earth's rotation rate is not consistent, and hence, Leap-Seconds are irregularly spaced and unpredictable. No Leap-Seconds were added between the Leap-Second of 1998 December 31 and the Leap-Second of 2005 December 31, while Leap-Seconds were added each year from 1972 to 1979 (including the two Leap-Seconds in 1972). The International Earth Rotation and Reference Systems Service (IERS), based in Frankfurt, Germany, usually decides to install a Leap-Second in the time scale about six months in advance of implementation.

Of course, the Earth's rotation rate does not suddenly slow down by one second, at certain intervals. The Earth's rotation rate has been continually slowing down, and this continues to be monitored by scientists.

Currently, the Earth's rotation rate, measured as UT1 (Universal Time-1 - Mean Solar Time at the Prime Meridian in Greenwich, England), is behind scientists' more consistent UTC (derived from International Atomic Time, determined by atomic clocks) by two-tenths of a second (clock correction known as DUT1, which is UT1 minus UTC). So, for the civil time scale to stay more consistent with the Earth's rotation rate, a Leap-Second is needed to slow down UTC by one second.

If the Leap-Second occurred today (2016 July 11), this would make the Earth's rotation rate in advance of UTC by two-tenths of a second. Then, it may take a couple years for the Earth to slow down enough, to the point where UT1 would again be behind UTC and another Leap-Second would be needed.

Of course, by December 31, UT1 may (or may not) actually be five-tenths or six-tenths of a second behind UTC. UTC is never allowed to advance more than nine-tenths of a second ahead of UT1, although usually a Leap-Second is added long before that could happen.

Leap-Seconds have proven to be a problem for computers. Hence, in 2005 there was a proposal to eliminate Leap-Seconds, possibly replacing them with Leap-Hours as a way to keep the civil time scale in-sync with the Earth's rotation rate. However, this issue has been quite controversial among scientists and government officials, so the decision to make any change has been delayed.

Precise time signals, which will include the Leap-Second on December 31 as well as the daily DUT correction, are now provided by government agencies via radio, telephone, and the Internet. This includes agencies such as the U.S. Naval Observatory (USNO), National Institute of Standards and Technology (NIST) [originally known as the National Bureau of Standards (NBS)] of the U.S. Department of Commerce, and the National Research Council (NRC) of Canada. Earlier in the 19th century, the Allegheny Observatory in Pittsburgh provided precise time signals to the railroads and some cities via the telegraph.

Radio time signals, with voice announcements each minute, are provided by three short-wave radio stations in North America: WWV in Fort Collins, Colorado and WWVH in Kekaha, Kauai, Hawaii, both operated by the National Institute of Standards and Technology, and CHU in Ottawa, Ontario, operated by the National Research Council of Canada. Radio-controlled clocks automatically receive the precise time from NIST-operated, long-wave radio station WWVB in Fort Collins, Colorado.

Internet Links to Additional Information ---

More on the Leap-Second -
Link 1 >>> http://www.timeanddate.com/time/leapseconds.html
Link 2 >>> https://en.wikipedia.org/wiki/Leap_second
Link 3 >>> http://earthsky.org/human-world/leap-second-june-30-december-31-why-need-controversy

More on Universal Time (including UT1 & UTC):
Link >>> http://en.wikipedia.org/wiki/Universal_Time

More on Coordinated Universal Time:
Link >>> http://en.wikipedia.org/wiki/Coordinated_Universal_Time

More on International Atomic Time:
Link >>> http://en.wikipedia.org/wiki/International_Atomic_Time

More on precise, international radio time services ---

WWV (SW), Fort Collins, Colorado (Voice announcements of precise time):
Link >>> https://en.wikipedia.org/wiki/WWV_%28radio_station%29

WWVH (SW), Kekaha, Kauai, Hawaii (Voice announcements of precise time):
Link >>> https://en.wikipedia.org/wiki/WWVH

CHU (SW), Ottawa, Ontario, Canada (Voice announcements of precise time):
Link >>> https://en.wikipedia.org/wiki/CHU_%28radio_station%29

WWVB (LW), Fort Collins, Colorado (For Radio-Controlled Clocks only):
Link >>> https://en.wikipedia.org/wiki/WWVB

More on precise time via telegraph in the 19th century, from Pittsburgh's Allegheny Observatory:
Link >>> http://spacewatchtower.blogspot.com/2016/03/some-states-to-abandon-daylight-saving.html

Related Blog Posts ---

"'Leap Second' Tue. Evening Due to Slowing Earth Rotation Rate." 2015 June 30.

Link >>> http://spacewatchtower.blogspot.com/2015/06/leap-second-tue-evening-due-to-slowing.html


"Slowing Earth Rotation Rate Necessitates June 'Leap Second'." 2015 Jan. 27.

Link >>> http://spacewatchtower.blogspot.com/2015/01/slowing-of-rotation-rate-necessitates.html

 

"Centennial: New Allegheny Observatory Dedication." 2012 Aug. 28.

Link >>> http://spacewatchtower.blogspot.com/2012/08/centennial-new-allegheny-observatory.html


"Second Added to All Clocks Saturday Evening by Scientists." 2012 June 29.

Link >>> http://spacewatchtower.blogspot.com/2012/06/second-added-to-all-clocks-saturday.html


"End of the "Leap Second"?" 2012 Jan. 17.

Link >>> http://spacewatchtower.blogspot.com/2012/01/end-of-leap-second.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2016 July 11.


                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >

Tuesday, July 5, 2016

On-Target: NASA's Juno Spacecraft Enters Polar Orbit of Jupiter

Juno obtained this color view on June 29, 2016
This is the last image of Jupiter taken by NASA's Juno spacecraft, as it approached Jupiter on 2016 June 29, at a distance of 3.3 million miles / 5.3 million kilometers from the Solar System's largest planet. After this photograph was taken, Juno's science .instruments were powered-down as it prepared for the difficult orbit insertion maneuver.
(Image Sources: NASA / JPL-Caltech/SwRI/MSSS)

By Glenn A. Walsh
Reporting for SpaceWatchtower

Late evening on American Independence Day (2016 July 4), and just one second difference from pre-burn predictions, NASA's Juno space probe entered polar orbit of the Solar System's largest planet, Jupiter.

The precarious orbit insertion maneuver occurred at the scheduled time of 11:05 p.m. Eastern Daylight Saving Time (EDT) / July 5 at 3:05 Coordinated Universal Time (UTC). However, NASA officials and scientists did not know the maneuver was successful until 11:53 p.m. / July 5 at 3:53 UTC, 48 minutes later, as the orbit insertion was accomplished by Juno's auto-pilot. This is because Jupiter is currently 48 light-minutes from Earth, and radio signals take 48 minutes to travel between Jupiter and the Earth, at this time.

Entering a highly elliptical orbit of Jupiter, which lasts for 53 days, was difficult and dangerous, as Juno had to risk Jupiter's heavy radiation belt, as well as debris orbiting the planet. This particular orbit will allow Juno to avoid Jupiter's dense radiation most of the time, but also make close investigations of Jupiter's North and South Poles as well as the Equator.

The spacecraft's nine science instruments and camera were deactivated before attempting the orbit insertion, to ensure that nothing interfered with the important engine burn; so, there are no actual photographs of the maneuver. However, the maneuver seemed to go flawlessly, when NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California received confirmation that Juno had actually entered orbit around Jupiter. JPL scientists worked along-side engineers from Lockheed Martin, the primary aerospace contractor for the Juno mission.

Prior to turning-off the camera, Juno took a time-lapse video of Jupiter and some of its moons, which NASA released to the public. This video included the first mission surprise: Jupiter's moon, Callisto, appeared dimmer than expected. Juno will take further images of Callisto during the mission.

At a 1:00 a.m. EDT / 5:00 UTC, July 5, NASA / Jet Propulsion Laboratory (California Institute of Technology) media briefing, where questions were taken from both news reporters and from the public via Social Media, Juno's principal science investigator Scott Bolton announced, “NASA did it again,” regarding the tricky space maneuver. He added, "The mission team did great. The spacecraft did great. We are looking great. It's a great day." Scott Bolton does space research at the Southwest Research Institute in San Antonio.

Rick Nybakken, Juno project manager from JPL agreed saying, "The spacecraft worked perfectly, which is always nice when you're driving a vehicle with 1.7 billion miles on the odometer. Jupiter orbit insertion was a big step and the most challenging remaining in our mission plan, but there are others that have to occur before we can give the science team members the mission they are looking for."

Jupiter is one of four “gas giant” planets in the Solar System (the others being Saturn, Uranus, and Neptune), whose clouds are primarily composed of hydrogen and helium. The inner planets, including Mercury, Venus, Earth, and Mars, as well as many objects in the Asteroid Belt and Kuiper Belt (including Pluto) are rocky-type planets.

It is hypothesized that Jupiter formed shortly after the formation of our Sun, and the gravity from Jupiter's massive body may have led to the formation of the other planets. By studying Jupiter, we may find clues to the formation of the Earth.

Juno has a big mission for investigating a big planet. The space probe's primary goal is to understand the origin and evolution of Jupiter, using nine major science instruments. During the mission, Juno will:

  1. More accurately measure Jupiter's gravity to try to determine if Jupiter has a solid planetary core, underneath the heavy cloud cover.
  2. Map Jupiter's intense magnetic field.
  3. Measure the amount of water and ammonia in the deep atmosphere, which could give a clue as to the planet's origin.
  4. Observe the planet's auroras.
  5. Study the cloud belts and the mysterious Red Spot, a huge cyclone larger than the Earth, that has existed for hundreds of years, but now seems to be shrinking in size.
  6. Use data accumulated to try to understand how giant planets form and their role in the organizing of the Solar System.
  7. As many planets being discovered around other stars are as large or larger than Jupiter, more information from Jupiter could help us understand solar systems around other stars.

In the beginning, Juno will complete two 53-day orbits, each known as a “Perijove Pass.” Juno's scientific instruments will be turned-back-on by August 27; this is when the first close-up pictures of Jupiter are expected. On October 19, Juno's engines will change the spacecraft's orbit to a much closer 14-day orbit, where it will stay until the end of the mission in 2018, when it will have completed 37 orbits of Jupiter.

Juno will descend as close as 3,000 miles / 5,000 kilometers to the cloud-tops of Jupiter, the closest any spacecraft has come to the planet. Juno's computer and electronics are sealed in a titanium vault, to protect them from Jupiter's massive radiation. However, Juno is still expected to encounter radiation in excess of 10 million dental X-rays during the mission. Hence, the space probe can only take so much radiation before systems will begin to fail, and the mission is slated to end before the radiation destroys the computer and electronics.

The Juno spacecraft was launched from the Cape Canaveral Air Force Station in Florida on 2011 August 5. However, it did not have enough fuel to go straight to Jupiter, which is why the flight took nearly five years to travel 1.8 billion miles / 2.8 billion kilometers. Juno first went into an elliptical orbit of the Sun.

In October of 2013, Juno passed by the Earth for an Earth gravity-assist (a.k.a. “sling-shot” maneuver), which gave the spacecraft the additional energy needed to reach Jupiter. This gravity-assist gave Juno a boost of more than 8,800 miles-per-hour / 3.9 kilometers-per-second.

For the first time for a NASA mission to the outer planets, the spacecraft is powered by solar energy, rather than by a type of nuclear power (radioisotope thermoelectric generator). Solar panels are normally used for powering Earth satellites and space probes to the inner planets, which are much closer to the Sun than Jupiter. Juno's three huge solar arrays will not only provide energy, 500 watts, for powering the nine scientific instruments, but they will also be key in stabilizing the spacecraft.

Juno is the second spacecraft to orbit Jupiter. The space probe Galileo orbited Jupiter from 1995 to 2003. Eventually, NASA allowed Galileo to burn-up in Jupiter's atmosphere, to prevent it from inadvertently crashing onto one of Jupiter's moons, and subsequently contaminating the moon with bacteria from Earth. Likewise, at the end of Juno's 20-month, $1.1 billion mission, it too will burn-up in Jupiter's atmosphere, for the same reason.

The European Space Agency (ESA) plans to send a Jupiter Icy Moon Explorer space probe to the Jupiter system in 2030, with a launch in 2022. This mission is the successor to the originally proposed Jupiter Ganymede Orbiter by ESA.

NASA has also proposed an Europa Multiple Fly-By Mission, which would be launched around 2022 and include the fly-by of Jupiter's moon Europa 32 times while orbiting Jupiter, as well as landing a spacecraft on this Galilean Moon.

Several more space probes have investigated Jupiter, while flying-by and continuing into the outer Solar System (except Ulysses). These included Pioneer 10 (1973), Pioneer 11 (1974—on its way to Saturn), Voyager 1 (1979—on its way to Saturn and Saturn's largest moon, Titan), Voyager 2 (1979—on its way to Saturn, Uranus, and Neptune), Ulysses (1992—on its way to a detailed study of the Sun), Cassini (2000—on its way to Saturn), and New Horizons (2007—on its way to Pluto).

The spacecraft's name, Juno, comes from the NASA acronym, JUpiter Near-polar Orbiter. However, the name was also chosen because in Greco-Roman mythology, the goddess Juno was the name of the wife of the god Jupiter. And, Juno had the power to peer through clouds, created by Jupiter to hide from his wife, and learn of her husband's mischief. Likewise, the Juno spacecraft has the power to peer through the planet Jupiter's dense clouds, to learn more of the secrets of our Solar System's largest planet.

Internet Links to Additional Information ---

More about Juno:
Link 1 >>> https://www.nasa.gov/mission_pages/juno/main/index.html
Link 2 >>> https://en.wikipedia.org/wiki/Juno_(spacecraft)

More about Jupiter: Link >>> https://en.wikipedia.org/wiki/Jupiter

More about robotic exploration of Jupiter:
Link >>> https://en.wikipedia.org/wiki/Exploration_of_Jupiter

Social Media sites to follow the Juno mission:
Facebook - Link >>> http://www.facebook.com/NASAJuno
Twitter - Link >>> http://www.twitter.com/NASAJuno

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2016 July 5.


                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >

Friday, July 1, 2016

Astronomical Calendar: 2016 July

Artist concept of Juno.
NASA's Juno space probe will go into polar orbit of Jupiter on the evening of American Independence Day, July 4, with the mission to investigate closer to the planet than any other spacecraft. And, this Summer will also mark the 40th anniversary of Viking 1 & 2, the first U.S. spacecraft to safely land on Mars.
More on Juno: Link >>> https://www.nasa.gov/mission_pages/juno/main/index.html
More on Viking 1 & 2: Link >>> http://mars.nasa.gov/programmissions/missions/past/viking/
(Artistic Image Sources: NASA, Jet Propulsion Laboratory / California Institute of Technology)

Astronomical Calendar for 2016 July: 
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2016.html#jul

Source: Friends of the Zeiss.
              2016 July 1.

                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >

Monday, June 20, 2016

Full Moon Summer Solstice


http://buhlplanetarium.tripod.com/pix/graphics/solsticeimage008.png
This diagram shows the position of the Earth, in relation to the Sun, at the time of the Summer Solstice, as well as the other solstice and equinoxes of the year. This year, June's Full Moon occurs on the day of the Summer Solstice in the Western Hemisphere.
(Graphic Source: ©1999, Eric G. Canali, former Floor Manager of Pittsburgh's original Buhl Planetarium and Institute of Popular Science and Founder of the South Hills Backyard Astronomers amateur astronomy club; permission granted for only non-profit use with credit to author.)
 

By Glenn A. Walsh
Reporting for SpaceWatchtower

This year, the beginning of Summer in the Northern Hemisphere is marked with a Full Moon. Both astronomical events occur on the same calendar date in the Western Hemisphere.

For 2016, the season of Summer begins in Earth's Northern Hemisphere (and the season of Winter begins in the Southern Hemisphere) at the moment of the June Solstice: Monday Evening, 2016 June 20 at 6:34 p.m. Eastern Daylight Saving Time (EDT) / 22:34 Coordinated Universal Time (UTC). The actual time of Full Moon occurs Monday morning at 7:02 a.m. EDT / 11:02 UTC, the time of the posting of this blog post. Although, technically, the Moon will be in the Waning Gibbous Phase at the moment of the Summer Solstice, it will, of course, look quite full.

A honey-hued-color Full Moon (particularly at extreme northern latitudes) in June, particularly around the time of the Summer Solstice, is considered the "Honey-Moon." This honey-hued effect is due to the Full Moon traveling low in the sky, very close to the southern horizon, throughout the night.

This may have led to the traditional term of "Honey-Moon," as weddings were traditionally held in June when the good weather days of Summer would begin. The term "Honey-Moon" can be traced as far back as 1552. At that time, marriage was compared to the phases of the Moon, with a Full Moon analogous to the wedding, the most happy time of a relationship.

Although the Full Moon does not occur on the Summer Solstice every year, the June Full Moon does travel close to the southern horizon, throughout the night, every year. As this is the time when the Sun is the highest in the sky for the entire year, this is also the time when the Moon is the lowest in the sky for the entire year.

On days around the time of the Summer Solstice this year, as the Full Moon sets early in the morning in the southwest, the Sun rises at about the same time in the northeast, on the opposite side of the celestial sphere. Likewise, when the Sun sets in the evening in the northwest, at about the same time the Full Moon will be rising in the southeast, on the opposite side of the celestial sphere. And, the locations of the rising and setting of the June Full Moon this year are approximately the same as the locations of the rising and setting of the Sun around the time of the Winter Solstice (December 20 to 22).

In etymology, the word solstice comes from the Latin terms sol (Sun) and sistere (to stand still). In ancient times, astronomers / astrologers / priests recognized that on one day of the year (in the Northern Hemisphere, near the day we now call June 21), the Sun would appear to reach its highest point in the sky for the year. The motion of the Sun's apparent path in the sky (what is known astronomically, today, as the Sun's declination) would cease on this day, before appearing to reverse direction.

Today, we know that, while the Sun does have motions, it is actually the motion of the Earth tilted on its axis 23.43715 degrees / 23 degrees 26 minutes 13.7 seconds away from the plane of the ecliptic (Earth's orbital plane around the Sun), while revolving around the Sun, that causes the Earth's seasons. Hence, as the Earth arrives at the point in its orbit around the Sun, when the north polar axis is most directly inclined toward the Sun, this marks the Summer Solstice in the Northern Hemisphere and the Winter Solstice in the Southern Hemisphere.

Alternately, the Winter Solstice in the Northern Hemisphere occurs when the Earth reaches the point in its orbit when the North Pole is most directly inclined away from the Sun. And, conversely, at this time Summer begins in the planet's Southern Hemisphere.

Although the Summer months in the Northern Hemisphere are known for the year's warmest weather, the Earth is actually at the point in its orbit farthest from the Sun (astronomically known as the point of aphelion) around July 5; the Earth's closest approach to the Sun (perihelion) each year is around January 2. Solar radiation, and hence the heat from the Sun, depends on the length of daylight and the angle of the Sun above the horizon. The tilt of the planet's axis toward the Sun determines the additional and more direct solar radiation received by a planet's Northern or Southern Hemisphere, and hence, the warmer season of the respective hemisphere.

The Vernal Equinox, when the season of Spring begins in the Northern Hemisphere (and the season of Autumn begins in the Southern Hemisphere), occurs between the Winter and Summer Solstices when the Earth reaches the point in its orbit around the Sun when the Earth's axis is inclined neither toward nor away from the Sun. Likewise, when the Earth reaches the point in its orbit around the Sun, between the Summer and Winter Solstices, when the Earth's axis is inclined neither toward nor away from the Sun, this is known as the Autumnal Equinox (beginning of Fall or Autumn) in the Northern Hemisphere; at this time Spring begins in the Southern Hemisphere. And, half-way between the beginning points of each season are Cross-Quarter Days, each related to traditional holidays: Groundhog Day (February 2), May Day (May 1), Lammas Day (traditionally, the first harvest festival of the year on August 1), and Halloween (October 31).

In ancient times, the Summer Solstice was known as Midsummer Day, in early calendars observed around June 24. Such early European celebrations were pre-Christian in origin. Many will associate this ancient holiday with the famous William Shakespeare play, “A Midsummer Night's Dream.” Some speculate that the play was written for the Queen of England, to celebrate the Feast Day of Saint John.

As with the Roman Catholic Church's decision to Christianize the pagan Winter Solstice festivals with the introduction of Christmas Day on December 25, the Church began to associate the Midsummer festivals with the Nativity of Saint John the Baptist on June 24. In the Bible, the Gospel of Saint Luke implies that John was born six months before the birth of Jesus, although no specific birth dates are given.

In addition to the Summer Solstice Full Moon being considered the “Honey-Moon,” to the Algonquin Indians of North America, the June Full Moon was known as the Strawberry Moon. This was due to the relatively short harvest season for strawberries, which always came in June.

In the Northern Hemisphere, the June Full Moon is also known as the Flower Moon and the Corn-Planting Moon. In Europe, the June Full Moon was known as the Rose Moon.

In the Southern Hemisphere, where the season of Winter is about to begin, the June Full Moon is known as the Oak Moon, Cold Moon, and Long-Night's Moon.
 
Links to Additional Information ---

Slooh Community Observatory live web-cast of Full Moon rising on the Summer Solstice - Monday Evening, 2016 June 20, 8:00 to 9:30 p.m. EDT / June 21, 0:00 to 1:30 UTC:
Link >>> http://live.slooh.com/stadium/live/june-solstice-full-moon

More on the Summer Solstice -
Link 1 >>> http://scienceworld.wolfram.com/astronomy/SummerSolstice.html
Link 2 >>> http://en.wikipedia.org/wiki/Summer_solstice

More on the Season of Summer: Link >>>
http://en.wikipedia.org/wiki/Summer

More on the history of Midsummer: Link >>>
http://en.wikipedia.org/wiki/Midsummer

Summer "Solstice Day" Annual Free-of-Charge Day, 1985 to 1991, at Pittsburgh's original Buhl Planetarium and Institute of Popular Science (a.k.a. Buhl Science Center):

Link >>> http://spacewatchtower.blogspot.com/2015/06/snowballs-on-first-day-of-summer.html

Special Thanks: Eric G. Canali, former Floor Manager of Pittsburgh's original Buhl Planetarium and Institute of Popular Science and Founder of the South Hills Backyard Astronomers amateur astronomy club.

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2016 June 20.


                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >

Thursday, June 16, 2016

100 Years Ago: Connecticut Observatory Opens w/out Telescope!

Van Vleck Observatory
Van Vleck Observatory of Wesleyan University in Middletown, Connecticut.
(Image Sources: Wikipedia.org , By Original uploader was Daydrmgirl at zh.wikipedia - Transferred from zh.wikipedia; transferred to Commons by User:Shizhao using CommonsHelper., CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=12864694 )

By Glenn A. Walsh
Reporting for SpaceWatchtower

One hundred years ago today, on 1916 June 16, the Van Vleck Observatory was dedicated on the campus of Wesleyan University in Middletown, Connecticut, just south of Hartford, the state capital. But, there was one problem. Due to the outbreak of World War I, they did not have a telescope!

They had everything else needed for a respectable 20th century academic observatory: a library, lecture hall, clock room, and two “computer” rooms (rooms where men and women “computers” used pencil, paper, and a mechanical calculator to compile data from observations).

In July of 1914, the famous telescope-maker Alvan Clark Company had ordered a 20-inch objective lens for the observatory's primary telescope, from Schott and Company in Germany. Very shortly after the order was placed, with the beginning of the First World War on 1914 July 28, the German company could not fulfill the order.

After the World War I Armistice of 1918 November 11, the order for the 20-inch objective glass was renewed in 1920, and the glass was delivered later that year. Mr. C.A.R. Lundin of the Alvan Clark Company ground the glass, which was installed in a Warner and Swasey mounting in July of 1922. First Light for this 20-inch refractor telescope (with a focal length of 27.6 feet) came shortly thereafter.

During the War, the Van Vleck Observatory made-do with two older telescopes which had been used by the University during the 19th century: a 12-inch refractor from the Alvan Clark Company (1868) and their first telescope, the 6-inch Fisk refractor from M. Lerebours telescope-maker in Paris (1838).

The Van Vleck Observatory is named after John Monroe Van Vleck, an astronomer and mathematics professor at Wesleyan University during the 19th and early 20th centuries (1853 to 1912). Professor Van Vleck's brother, Joseph Van Vleck, donated $25,000 to start a fund to build a new observatory for Wesleyan University in 1903. With good investing of the fund, along with additional donations from other members of the Van Vleck family, the money for the building and equipment was secured and ground was broken for the Van Vleck Observatory in 1914.

However, Professor Van Vleck passed-away on 1912 November 4. Dr. Frederick Slocum of the famous Yerkes Observatory in Wisconsin was hired to finish the observatory project, and he became the Van Vleck Observatory's first Director. Dr. Slocum worked with the architect, Henry Bacon (best known for his design of the Lincoln Memorial in Washington D.C.), to create a state-of-the-art facility, well-suited for New England winters.

In addition to university instruction, Dr. Slocum, who continued as Van Vleck Observatory Director until 1944, designed the program to use the 20-inch refractor for measuring the distances to stars by taking star field images for stellar parallax measurements. The 20-inch refractor is now used during weekly observing nights, open to students and the general public. A 24-inch Perkin reflector telescope hosted in a separate observatory dome, donated to the Van Vleck Observatory in 1971, is now the Observatory's primary research instrument.

The Van Vleck Observatory's problem during World War I is somewhat similar to a problem Pittsburgh's original Buhl Planetarium and Institute of Popular Science experienced during World War II. Buhl Planetarium's third-floor observatory was finished with the rest of the building in 1939. However, the telescope, a rather unique 10-inch Siderostat-type Refractor Telescope (which will observe a 75th anniversary on November 19), would not be ready until 1941. But, Buhl Planetarium managers had a plan for the interim two years.

Along with the acquisition of Buhl's Zeiss II Planetarium Projector (on behalf of the Projector's legal owner, the City of Pittsburgh), the Buhl Planetarium also ordered a portable telescope from the Carl Zeiss Optical Works in Jena, Germany in 1939, for use in the Observatory. To the dismay of Buhl officials when opening the package from Germany, they received a 4-inch terrestrial refracting telescope (which uses additional optics to show a right-side-up image); they had ordered an astronomical refractor telescope (which has fewer lenses to degrade the image and shows an upside-down image).

With the commencement of World War II on 1939 September 1, they could not return the telescope to Germany and have an astronomical refractor sent in its place. Hence, they had to make-do with a terrestrial refractor. So, today the City of Pittsburgh owns a good Zeiss telescope (now used at the Henry Buhl, Jr. Planetarium and Observatory of The Carnegie Science Center) with a very interesting history!

Links to Additional Information ---

More on the history of the Van Vleck Observatory:
Link >>> http://www.wesleyan.edu/astro/van-vleck/history.html

More on Professor John Monroe Van Vleck:
Link >>> https://en.wikipedia.org/wiki/John_Monroe_Van_Vleck

More on World War I: Link >>> https://en.wikipedia.org/wiki/World_War_I

More on the Astronomical Observatory of Pittsburgh's original Buhl Planetarium and Institute of Popular Science:
Link >>> http://spacewatchtower.blogspot.com/2011/11/70th-anniversary-buhl-planetarium.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2016 June 16.


                                                               Historic 10-inch Siderostat-type Refractor Telescope at Pittsburgh's original Buhl Planetarium and Institute of Popular Science.
        2016: 75th Year of Pittsburgh's Buhl Planetarium Observatory
     Link >>> http://spacewatchtower.blogspot.com/2016/01/astronomical-calendar-2016-january.html

                             Like This Post? - Please Share!

Want to receive SpaceWatchtower blog posts in your inbox ?
Send request to < spacewatchtower@planetarium.cc >..

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://buhlplanetarium.tripod.com/fotz/ >
Electronic Mail - < gawalsh@planetarium.cc >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
Also see: South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin: Writing, Essays, Pgh. News, & More: < http://www.barnestormin.blogspot.com/ >
About the SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
http://buhlplanetarium.tripod.com/#news >
Twitter: < https://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* 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 >