Monday, March 27, 2017

Public Invited to Search for Planets in Other Star Systems

KeckTelescopes-hi.png
W.M. Keck Observatory on Mauna Kea in Hawaii.
(Image Sources: Wikipedia.org , By T. Wynne / JPL - http://planetquest.jpl.nasa.gov/images/keckTelescopes-hi.tif, Public Domain, https://commons.wikimedia.org/w/index.php?curid=4963229 )

By Glenn A. Walsh
Reporting for SpaceWatchtower

Last month, NASA opened an Internet web-site to engage the public in the search for the long-sought “Planet Nine” in the outer reaches of our Solar System. A huge data-set has also been released on the Internet, by a team led by the Carnegie Institution for Science (a.k.a. Carnegie Institution of Washington), inviting the public to help in the search for exo-planets, planets outside of our Solar System.

With a technique called radial velocity being used to help hunt for exo-planets, this data-set is the largest collection of observations utilizing this particular technique. It took more than two decades for the W.M. Keck Observatory on Mauna Kea in Hawaii to collect all of these observations. At an elevation of 13,600 feet / 4,145 meters, Keck's twin telescopes, each with a 10-meter / 33-foot mirror-aperture, saw “first-light” in the mid-1990s.

The huge observation data-set is being made available for public use, along with a computer software package to help process the data and an on-line tutorial of how to use the data-set. With almost 61,000 observations of more than 1,600 nearby stars, scientists are hoping that fresh, public eyes using this user-friendly data-base will bring new results in the search for exo-planets.

Internet links to this data-base, along with tools to assist in its use, are located at the end of this blog-post.

Much of this observation work was done by a spectrometer mounted on the Keck-I Telescope called HIRES. HIRES (High Resolution Echelle Spectrometer), a large and complex instrument of the Keck Observatory, analyzes the light spectra coming into the telescope from the various star systems observed.

"HIRES was not specifically optimized to do this type of exoplanet detective work, but has turned out to be a workhorse instrument of the field", said Steve Vogt of the University of California Santa Cruz, who built the instrument. "I am very happy to contribute to science that is fundamentally changing how we view ourselves in the universe."

Thus far, scientists looking over this data have found more than 100 possible exo-planets, including one orbiting Star GJ-411, the fourth closest star to our Solar System (8.1 light-years from Earth). An academic research paper about this find was recently published in the scientific journal, The Astronomical Journal.

“This is an amazing catalog, and we realized there just aren’t enough of us on the team to be doing as much science as could come out of this dataset,” says Jennifer Burt, a Torres Postdoctoral Fellow in the Massachusetts Institute of Technology’s (MIT) Kavli Institute for Astrophysics and Space Research. “We’re trying to shift toward a more community-oriented idea of how we should do science, so that others can access the data and see something interesting.”

"I think this paper sets a precedent for how the community can collaborate on exoplanet detection and follow-up", said team-member Johanna Teske of Carnegie’s Observatories and Department of Terrestrial Magnetism. “With NASA’s TESS mission on the horizon (scheduled for launch a year from now), which is expected to detect 1000+ planets orbiting bright, nearby stars, exoplanet scientists will soon have a whole new pool of planets to follow up.”

Keck Observatory Observation Data-Base: Link >>> http://home.dtm.ciw.edu/ebps/

Software Package (Downloadable) to Assist with Searching Data-Base:
Link >>> http://www.stefanom.org/console-2/

On-Line Tutorial for use of Software Package: Link >>> http://oklo.org/

Internet Links to Additional Information ---

News Release from the Carnegie Institution for Science:
Link >>> https://carnegiescience.edu/news/team-makes-planet-hunting-group-effort-finds-more-100-candidates

News Release from the Massachusetts Institute of Technology:
Link >>> http://www.rdmag.com/news/2017/02/scientists-make-huge-dataset-nearby-stars-available-public?et_cid=5828674&et_rid=544605860&location=top&et_cid=5828674&et_rid=544605860&linkid=content

Carnegie Institution for Science: Link >>> https://en.wikipedia.org/wiki/Carnegie_Institution_for_Science

W.M. Keck Observatory: Link >>> https://en.wikipedia.org/wiki/W._M._Keck_Observatory 

HIRES - High Resolution Echelle Spectrometer:
Link >>> https://en.wikipedia.org/wiki/W._M._Keck_Observatory#Instruments

TESS: Transiting Exo-Planet Survey Satellite:
Link >>> https://en.wikipedia.org/wiki/Transiting_Exoplanet_Survey_Satellite

Citizen Science Projects: Link >>> http://buhlplanetarium2.tripod.com/FAQ/citizenscience.html

Related Blog Post ---

"Citizen Science: Help NASA Find 'Planet Nine'." 2017 March 10.

Link >>> http://spacewatchtower.blogspot.com/2017/03/citizen-science-help-nasa-find-planet.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2017 March 27.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
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gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >

Sunday, March 19, 2017

Season of Spring Begins Early Monday Morning

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 Vernal Equinox, the official beginning of the Season of Spring, as well as the other solstices and equinox of the year.
(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

The Vernal Equinox, which marks the beginning of the Season of Spring in Earth's Northern Hemisphere, occurs for 2017 on Monday Morning, March 20 at 6:29 a.m. Eastern Daylight Saving Time (EDT) / 10:29 Coordinated Universal Time (UTC).

In the Southern Hemisphere, this marks the astronomical beginning of the Season of Autumn.

On the day of Equinox, the Sun appears directly overhead at local Noon on the Equator. At the moment of Equinox, the Northern and Southern Hemispheres of Earth are illuminated equally. And, the time of Equinox is the only time when the terminator (dividing line on Earth between daylight and darkness) is perpendicular to the Equator.

This, and the reason for seasons on Earth in the first place, is due to the fact that Earth rotates on its axis, which is tilted at a 23 degrees, 26 minutes, 13.4 seconds (23.43705 degrees) angle from the plane of the Earth's orbit around the Sun. As the Earth revolves around the Sun, this axial tilt causes one hemisphere of the planet to receive more direct solar radiation during that hemisphere's Season of Summer and much less direct solar radiation a half-year later during that hemisphere's Season of Winter. As mentioned, during an Equinox [about half-way between Summer and Winter (for Autumn or Fall), and about half-way between Winter and Summer (for Spring)] both planetary hemispheres receive an equal amount of solar radiation.

In Latin, Equinox, is defined as equal-night, the day when daylight and darkness are about equal in length. Such actual equal-night never occurs on the actual date of an Equinox on Earth. This is due to the fact that the Sun is so large, in relation to the Earth, and hence, the entire Sun does not appear at actual sunrise, only a portion of the Sun; it takes a few more minutes for the entire Sun to appear above the horizon. Also, due to the refractive nature of Earth's atmosphere, daylight can be seen before the Sun's disk can be observed.

The date of actual equal-night varies by a location's longitude and latitude. At the Earth's Equator, daytime is always longer than night. Hence, the Equator never has equal-night.

While the Vernal Equinox, the true beginning of the Season of Spring, occurs on March 20 at 6:29 a.m. EDT / 10:29 UTC, the literal Equinox for Spring, termed the Spring Equilux, actually occurs each year a few days earlier, usually around March 16 or 17 (depending on the specific location).

The Vernal Equinox is used in the solar calendars of Iran and Afghanistan as the beginning of their calendar year. In ancient times, the Vernal Equinox, then celebrated by the old style calendar on or near March 25, was also the beginning of the calendar year for many ancient civilizations.

An urban legend that has been making the rounds for decades has it that eggs can be stood on their ends only during an Equinox, whether the Vernal Equinox in the Spring or the Autumnal Equinox in the Fall. This is completely false. Depending greatly on the size and shape of the particular egg, eggs can be stood on their ends any day of the year! Astronomy has nothing to do with whether an egg can stand on its end. If an egg can stand on its end on the Equinox (and, due to the shape and size of some eggs, this is not even possible), it can stand the same way any other day of the year.

In the last few years, with the help of the Internet and Social Media, another urban legend has become prevalent. Now it is claimed that brooms can stand on their own, on their bristles, only on an Equinox day. This is also false. Again, as with eggs, if a broom can stand on its bristles by itself (this usually only works with newer brooms, with more even bristles) on an Equinox, it can do so any day of the year!

This year, the Primary Moon Phase of Last Quarter for March occurs just a few hours after the Vernal Equinox: March 20 at 11:58 a.m. EDT / 15:58 UTC.

There is now an effort to have the day of the Vernal Equinox designated to commemorate the life of the first female astronomer, Hypatia of Alexandria, in ancient Egypt: Hypatia Day / Women in Science Day. Astronomical historian Ari Belenkiy, who finished an academic paper in 2016 on the life and death of Hypatia, has started an effort to have the day of the Vernal Equinox, March 20, designated by the Canadian Parliament as a day commemorating Hypatia's life. According to Professor Belenkiy, Hypatia's last days were dedicated to finding the exact time of the Vernal Equinox.

Hypatia was a Greek astronomer, mathematician, and philosopher, daughter of the mathematician Theon Alexandricus, who lived in Alexandria, Egypt during the late 4th and early 5th centuries. At that time Alexandria was part of the Eastern Roman Empire, which had a great rivalry with the Church of Rome. This led to deep divisions in Alexandria.

Due to the fog of time, there is much dispute regarding the events surrounding the death of Hypatia. According to the Church historian Socrates Scholasticus, a clique of Bishop Cyril's zealots killed Hypatia, due to a deep conflict between the Governor and Bishop of Alexandria. Hypatia's astronomical calculations regarding the date of Easter may have set the mob against her.

Although none of Hypatia's writings survive, she is reported to have made significant academic contributions in the fields of Astronomy and Mathematics.

The beginning of Spring also marks the beginning of the National Cherry Blossom Festival held each year in Washington, DC. This festival commemorates the 1912 gift of 3,000 cherry trees from the Mayor of Tokyo to the City of Washington. This year, the festival runs from March 15 through April 16.

Physicians have declared the first week of Spring as Medicine Cabinet Clean-Up Week. They urge families, as part of their annual Spring cleaning, to clean-out the medicine cabinet of old and expired pharmaceuticals which are no longer being used. This would prevent other family members from using these old drugs by accident, or the beginning of drug abuse.

Internet Links to Additional Information ---

Vernal Equinox: Link >>> http://scienceworld.wolfram.com/astronomy/VernalEquinox.html

Season of Spring: Link >>> http://en.wikipedia.org/wiki/Spring_%28season%29

Equinox: Link >>> http://en.wikipedia.org/wiki/Equinox

Earth's Seasons: Link >>> http://en.wikipedia.org/wiki/Season

Tilt of a planet's axis: Link >>> http://en.wikipedia.org/wiki/Axial_tilt

Hypatia:
Link 1 >>> https://en.wikipedia.org/wiki/Hypatia
Link 2 >>> http://booksandjournals.brillonline.com/content/journals/10.1163/15700720-12341264

Petition to designate March 20 to commemorate the life of Hypatia:
Link >>> https://www.change.org/p/canada-s-parliament-commemorating-the-first-female-astronomer-hypatia-of-alexandria

National Cherry Blossom Festival, Washington:
Link >>> http://www.nationalcherryblossomfestival.org/?id=404

Medicine Cabinet Clean-Up Week: Link >>> http://www.prnewswire.com/news-releases/include-medicine-cabinets-on-your-spring-cleaning-list-300042760.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.
             2017 March 19.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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, March 10, 2017

Citizen Science: Help NASA Find 'Planet Nine'


This is an artist's concept of a cool, Brown-Dwarf Star, a type known as a "Y-Dwarf," which is one possibility of being the proposed Planet Nine. Such "Y-Dwarf" stars are the coldest star bodies known, with temperatures that can be cooler than the human body! Hence, such an object in the Outer Solar System would be very difficult to find, as it would generate or reflect very little light.
(Image Source: NASA / Jet Propulsion Laboratory of the California Institute of Technology)

By Glenn A. Walsh
Reporting for SpaceWatchtower

NASA is seeking help from Citizen Scientists – that is, regular people who have not trained to be scientists - to help find the elusive “Planet Nine” (which some people also refer to as Planet X), which scientists are convinced exists in our Outer Solar System. Although the Planet Pluto, originally considered the ninth planet, was re-designated as a “Dwarf Planet” about a decade ago due to its small size, scientists recently hypothesized that one (or possibly more than one) much larger, and very difficult to see, planet is still yet to be found beyond the orbit of Neptune.

NASA has funded a new Internet web-site, titled Backyard Worlds: Planet 9 (Internet link to this web-site at the end of this blog-post), for members of the general public to assist with the search for Planet Nine, and possibly other yet-unfound celestial bodies between the orbit of Neptune and the closest star (not including our Sun) to our Solar System, Proxima Centauri. Proxima Centauri is 4.25 light-years from Earth, and in that distance there possibly is one or more planetary bodies that are very difficult to find.

The data-base used in the Backyard Worlds: Planet 9 web-site comes from a scan of stars in the entire sky, between 2010 and 2011, by NASA's Wide-Field Infrared Survey Explorer (WISE) mission. While it may be difficult to find outer planets using normal light, it is hoped that these objects can be found in a WISE infrared scan.

"There are just over four light-years between Neptune and Proxima Centauri, the nearest star, and much of this vast territory is unexplored," said lead researcher Marc Kuchner, an astrophysicist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Because there's so little sunlight, even large objects in that region barely shine in visible light. But by looking in the infrared, WISE may have imaged objects we otherwise would have missed."

On the new web-site, public participants can view brief "flip-book" movies of WISE scans of parts of the sky. It is believed that human eyes, looking at these infrared scans, could discern objects more readily than would a computer search-algorithm. There are some things that human eyes can still do better than a computer!

In addition to the possibility of finding Planet Nine, or other possible planets, asteroids / planetoids, or comets,  Brown-Dwarf Stars in the vicinity of our Solar System, some known as "Y-Dwarfs" (somewhat similar to Jupiter), may also be found in this new search. It may actually turn-out that Planet Nine is a Y-Dwarf or Brown-Dwarf.

Once a public participant views these brief movies, if they find an object that seems not to be a normal star, they can contact a Jet Propulsion Laboratory scientist (by flagging a questionable object) about the find. If it turns out that a new planet or a Y-Dwarf or Brown-Dwarf Star has actually been discovered, the citizen scientist(s) who participated in the discovery will be credited in the scientific literature.

So, give the new Backyard Worlds: Planet 9 web-site a try and see if you can find any yet-unchartered worlds. And, if NASA confirms that you did help find a new world, let SpaceWatchtower know (E-Mail address: < spacewatchtower@planetarium.cc >); we will include your name and your new discovery in an up-coming SpaceWatchtower blog-post!

Internet Link to the Backyard Worlds: Planet 9 Web-Site:

Internet Links to Additional Information ---

NASA's Wide-Field Infrared Survey Explorer (WISE) mission:
Link >>> https://en.wikipedia.org/wiki/Wide-field_Infrared_Survey_Explorer

Planet Nine: Link >>> https://en.wikipedia.org/wiki/Planet_Nine

Planet X: Link >>> https://en.wikipedia.org/wiki/Planets_beyond_Neptune

Brown-Dwarf Stars: Link >>> https://en.wikipedia.org/wiki/Brown_dwarf

Y-Dwarf Stars: Link >>> https://en.wikipedia.org/wiki/Brown_dwarf#Spectral_class_Y

"NASA-funded Website Lets the Public Search for New Nearby Worlds."
NASA / Jet Propulsion Laboratory 2017 Feb. 15.
Link >>> https://www.jpl.nasa.gov/news/news.php?feature=6747

More Citizen Science Projects:
Link >>> http://buhlplanetarium2.tripod.com/FAQ/citizenscience.html

Related Blog Posts ---

Walsh, Glenn A.
"Public Invited to Search for Planets in Other Star Systems." Blog-Post.
SpaceWatchtower 2017 March 27.
Link >>> http://spacewatchtower.blogspot.com/2017/03/public-invited-to-search-for-planets-in.html

Walsh, Glenn A.
"Undiscovered 'Planet Nine' May Be Cause of Tilt of Our Solar System." Blog-Post.
SpaceWatchtower 2016 Oct. 22.
Link >>> http://spacewatchtower.blogspot.com/2016/10/undiscovered-planet-nine-may-be-cause.html

Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2017 March 10.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >

Wednesday, March 1, 2017

Astronomical Calendar: 2017 March

Image result for images daylight savings time
Daylight Saving Time begins on Sunday Morning, 2017 March 12, at 2:00 a.m. Local
Prevailing Time. (Image Source: Austin College, Sherman TX)

Astronomical Calendar for 2017 March: 
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2017.html#mar

 Related Blog Post ---


"Astronomical Calendar: 2017 February." 2017 Feb. 1.

Link >>> http://spacewatchtower.blogspot.com/2017/02/astronomical-calendar-2017-february.html


Source: Friends of the Zeiss.
              2017 March 1.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >

Sunday, February 19, 2017

Two Dim Comets May Be Visible in a Telescope


Comet45PHMPgif
Radar image of the "Green" Comet 45P / Honda-Mrkos-Pajdušáková on
2017 February 12, by the huge Arecibo Radio Telescope in Puerto Rico. This
display combines 13 images of the comet received over two hours. This is only
the seventh comet to come close enough to be imaged by radar. On 2011 August
19 and 20, it became only the fifteenth comet to be detected by a ground radar
telescope.
(Image Sources: Arecibo Observatory, NASA, National Science Foundation, Sky and Telescope
Magazine )

By Glenn A. Walsh
Reporting for SpaceWatchtower

At the present time, two dim comets may be visible in a telescope (and, possibly binoculars), if you know where to look. While the “Green” Comet was in the early morning sky earlier this month, now both the Green Comet and Encke's Comet are in the evening sky.

American astronomer Fred Whipple described a comet as a “dirty snowball.” Comets are a combination of rocks, dust, water ice, and other frozen gases, from the early days of our Solar System.

The solid core of a comet is known as the nucleus. Streams of dust and gas released from the comet, as it nears the Sun, form a thin atmosphere around the comet nucleus called the coma. The coma is composed mostly (90 per-cent) of water, with dust making-up the rest of the coma.

Most, but not all, comets have one or more visible tails. The tail(s), which are usually not visible in the Outer Solar System, are caused by solar radiation as the comet comes closer to the Sun; this radiation usually is too weak to create tails in the Outer Solar System. Normally, a comet's tail(s) points away from the Sun, no matter the direction of movement of the comet; hence, a comet leaving the Inner Solar System often has a tail pointing in the direction of the comet's motion.

Comets usually have a highly-eccentric, elliptical orbit around the Sun, which brings a comet into the Inner Solar System for a short time, while it spends most of its time in the Outer Solar System. Short-period comets originate in the Kuiper Belt, just beyond the orbit of the Planet Neptune, while long-period comets are thought to originate in the Oort Cloud, a spherical cloud of icy bodies beyond the Kuiper Belt.

                                                    The “Green” Comet

The first one, nick-named the “Green” Comet due to its coloration, is actually Comet 45P / Honda-Mrkos-Pajdušáková. This comet passed closest to the Earth on February 11. At that time it was 7.4 million miles / 12 million kilometers from Earth. This distance can also be expressed as 0.08 Astronomical Units (1 A.U. or Astronomical Unit is the mean distance between the Sun and the Earth) and 30 times the mean distance between the Earth and the Moon.

At this distance, the Green Comet cannot be seen with the naked-eye; the astronomical Visual Magnitude at its closest point to Earth was expected to be around +6.5 to +7, but in reality it never was brighter than +8. It might be seen with strong binoculars, but a telescope is best for trying to find this comet. Unlike stars which shine their own light and appear as pin-points of light in the sky, comets only reflect sunlight. Hence, they appear as diffuse, fuzzy objects, which make them even more difficult to find.

The Green Comet may still be visible until the end of February. However, it will be a challenge to find. You will need a dark sky, away from city lights. Until a few days ago, this was even more complicated as the Moon was in the early morning sky. But, now the comet is rising in the late evening sky as the Moon rises even later. However, as the end of February gets closer, the comet will be fading in brightness.

The best time to view this comet is around 10:00 to 11:00 p.m. local time. As the comet fades, it will be moving through the constellations Corona Borealis, Boötes, Canes Venatici, Ursa Major and into Leo the Lion. Internet links to additional news articles, which include star charts to help find the comet, are located at the end of this blog-post.

The Green Comet was discovered on 1948 December 3 by Japanese astronomer Minoru Honda. It is named for Minoru Honda, Czech astronomer Antonin Mrkos, and Slovak astronomer Ludmila Pajdusakova. The comet appears green because it emits diatomic carbon, which glows green in the near-vacuum of Outer Space.

This apparition of the Green Comet is the second-closest to Earth between the years 1900 and 2043. The comet's closest approach to Earth came in August of 2011, when it came as close as 0.06 A.U or 5.6 million miles / 9.01233 million kilometers. While this comet comes toward the Sun fairly often (it is a short-period comet with an elliptical orbit of 5.25 years), the next time it is bright from Earth's vantage-point will be in October of 2032 when it is expected to reach a Visual Magnitude of +7.

                                                         Encke's Comet

Comet Encke or Encke's Comet is now visible in the evening sky, but will only be visible through early March. Like the Green Comet, Encke's Comet is not bright enough to be seen with the naked-eye (it has a very low albedo, reflecting only 4.6 per-cent of the light it receives), but it may be visible in binoculars or a telescope.

Enke's Comet is currently visible in the western sky about 90 minutes after local sunset. It is to the left of the Great Square of Pegasus, near the planets Mars and Venus. At the end of this blog-post is an Internet link to pages that show a map of how to find Comet Encke.

Encke's Comet was discovered in 1786 by French astronomer and surveyor Pierre Mechain. However, it was not immediately recognized to be a comet. It was not understood to be a periodic comet until 1819, when its orbit was calculated by German astronomer Johann Franz Encke.

Hence, as with the more famous Halley's Comet, Encke's Comet is one of the few comets named after the person who computed the comet's orbit, instead of the comet's discoverer. In fact, Encke's Comet was the first periodic comet discovered after Halley's Comet.

Encke's Comet has the shortest orbital period, 3.3 years, of any reasonably bright comet. A fainter comet, 311P / PANSTARRS, has an orbital period of 3.2 years.

In 1978, Slovak astronomer Lubor Kresak proposed that a fragment of Comet Encke may be the cometary body that caused the 1908 Tunguska Event. On the morning of 1908 June 30, a huge explosion occurred over a sparsely-settled area of Siberia in Russia known as the Stony Tunguska River Valley, which flattened 1,200 square-miles / 2,000 square-kilometers of forest, but caused no human casualties. The cause of the Tunguska Event, which was not observed by any living person, is thought to be an air-burst explosion of the atmospheric entry of a meteoroid, asteroid, or comet.

Internet Links to Additional Information ---

Information & Maps On How to View the 2 Comets -

"Green" Comet:
Link 1 >>> http://www.skyandtelescope.com/observing/green-comet-zooms-moonless-skies/
Link 2 >>> http://astrobob.areavoices.com/2017/02/14/goodbye-moon-but-will-the-green-comet-still-show/
Link 3 >>> http://earthsky.org/astronomy-essentials/comet-45phonda-mrkos-pajdusakova-new-years-eve

Encke's Comet:
Link 1 >>> https://theskylive.com/encke-tracker
Link 2 >>> https://stardate.org/astro-guide/gallery/evening-comet


The "Green" Comet - Comet 45P / Honda-Mrkos-Pajdušákov:

Encke's Comet - Comet Encke: Link >>> https://en.wikipedia.org/wiki/Comet_Encke

Tunguska Event: Link >>> https://en.wikipedia.org/wiki/Tunguska_event

Related Blog Posts ---

"Comet of 1491: Self-Correction of Science." 2016 Feb. 20.

Link >>> http://spacewatchtower.blogspot.com/2016/02/comet-of-1491-self-correction-of-science.html

 

"Comet Lovejoy: Best View Next 2 Weeks." 2015 Jan. 7.

Link >>> https://spacewatchtower.blogspot.com/2015/01/comet-lovejoy-best-view-next-2-weeks.html

 

"Comet ISON vs. the Solar Storm." 2013 Nov. 26.

Link >>> http://spacewatchtower.blogspot.com/2013/11/comet-ison-vs-solar-storm.html

 

"Comet: Source of Mysterious Water on Jupiter." 2013 May 4.

 Link >>> http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/pearcee/pe-jupiterwater.html

 

"Comet of the Century?" 2013 Jan. 19.

Link >>> https://spacewatchtower.blogspot.com/2013/01/comet-of-century.html


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2017 February 19.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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, February 10, 2017

Friday Night's Dim Penumbral Lunar Eclipse w/ Web-Cast

Lunar eclipse chart close-2017Feb11.png
This graphic shows how the Moon travels through the Earth's Penumbral Shadow during the
Penumbral (partial) Lunar Eclipse of 2017 February 10 to 11. The central gray area (analogous
to a "donut-hole") represents the Umbral (darker) Shadow, while the Penumbral (lighter) Shadow
would be represented by the circle comprising the rest of the "donut."
(Graphic Source: Wikipedia.org , By SockPuppetForTomruen at English Wikipedia - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=17111804 )

By Glenn A. Walsh
Reporting for SpaceWatchtower

The first eclipse of 2017, during the Full Moon of February, will be a Penumbral (partial) Lunar Eclipse, or Eclipse of the Moon, which may be dimly visible Friday to Saturday, 2017 February 10 to 11 throughout most of the world, except extreme western Alaska, extreme eastern Asia, Australia, New Zealand and most of the Pacific Ocean. An Internet web-cast of the event will be available for areas where this eclipse cannot be seen, or for areas where inclement weather precludes viewing.

Any Lunar Eclipse or Eclipse of the Moon, whether Total, Partial, or Penumbral, is the type of eclipse which is safe to look at with the naked-eyes, binoculars, and telescopes.

During an Eclipse of the Moon, the Earth's solar shadow shines on part or all of the Moon, always at the time of a Full Moon (when the Moon, Earth, and Sun, in that order, lie in a straight line). As sunlight strikes our planet, the Earth actually casts two shadows into Outer Space: the main and darker, cone-shaped Umbral Shadow, along with the secondary and dimmer Penumbral Shadow which surrounds the Umbral Shadow.

In a Total Lunar Eclipse, the Earth's Umbral Shadow completely envelops the Moon, after the Moon passes through the Penumbral Shadow. In the case of a Partial Eclipse of the Moon, only part of the Moon is covered by the Umbral Shadow, but again, the Moon does also pass through the Penumbral Shadow.

During a Penumbral Eclipse of the Moon, only the dimmer Penumbral Shadow covers part or all of the Moon. In the case of the February 10 to 11 eclipse, a Penumbral (partial) Lunar Eclipse will occur, as the Moon does not completely enter the Earth's Penumbral Shadow.

A Penumbral Eclipse of the Moon is much dimmer than a Partial Eclipse of the Moon or a Total Eclipse of the Moon. The Moon is not dimmer, but the shading of the Moon is much lighter than seen during other eclipses, making the Moon appear almost as bright as normal.

The shading of the Moon during a Penumbral Eclipse is extremely subtle, and not everyone may be able to tell when the eclipse is occurring by observation. So, although some people may notice that the Moon is slightly dimmer than usual, other people may not notice the difference. However, despite not being a complete Penumbral Eclipse, this particular eclipse does traverse the darkest areas of the Penumbral Shadow, so it may be a little easier to notice than other Penumbral Eclipses.

Technically, the entire eclipse lasts four and one-third hours. However, the human eye cannot perceive the entire eclipse, due its dim nature. Likely, one or two hours of the eclipse, centered around the time of greatest eclipse, may be visible to most people.

As this eclipse occurs when the Moon is rising in the Western Hemisphere (on the evening of February 10), it is best seen in the eastern sections of North and South America; the farther west the observer, the more the observer will have to contend with evening twilight. Asian viewers have the opposite problem, as they will need to contend with morning twilight (on February 11) as the Moon is about to set. The entire eclipse will be visible to viewers in Europe, Africa, Middle East, Greenland, Iceland, Quebec, New England, and most of Brazil.

To determine when the Moon rises and / or sets in your location, you can enter your locality data on a form of an Internet web page managed by the U.S. Naval Observatory; both Form A (for U.S. Cities and Towns) and Form B (for Locations Worldwide) are on this web page. A link to this web page is located at the end of this blog-post.

               Times of Penumbral (partial) Lunar Eclipse Phases – 2017 February 10 to 11
                        (EST = Eastern Standard Time; UTC = Coordinated Universal Time)

Penumbral Lunar Eclipse Begins:                  Feb. 10, 5:34:16 p.m. EST / 22:34:16 UTC
Ecliptic Conjunction:                                       Feb. 10, 7:32:51.3 p.m. EST / Feb. 11, 0:32:51.3 UTC
Moon Phase - Full Moon:                               Feb. 10, 7:33 p.m. EST / Feb. 11, 0:33 UTC
Greatest Penumbral Lunar Eclipse:               Feb. 10, 7:43:52.9 p.m. EST / Feb. 11, 0:43:52.9 UTC
Penumbral Lunar Eclipse Ends:                     Feb. 10, 9:53:26 p.m. EST / Feb. 11, 2:53:26 UTC

Special Note: Although the times given for the beginning and ending of the Penumbral Eclipse are the correct times, it is highly unlikely that the beginning and ending can be viewed visually. On average, a Penumbral Eclipse is only visible a half-hour before until a half-hour after the time of greatest eclipse.

Observations of the exact times when the Penumbral Eclipse is actually first visible, and when the Eclipse is actually no longer visible, would be valuable to Science. For those interested in making such serious observations, a photometer giving the light intensity coming from the Moon would be helpful.

The bright object to the lower left the Moon (during the evening hours of Feb. 10) and above and closer to the Moon (in the morning hours of Feb. 11), during this eclipse, is the Star Regulus, brightest star of the well-known Constellation Leo the Lion and one of the brightest stars in the sky. About 11 hours after the eclipse (February 11, 9:00 a.m. EST / 14:00 UTC) the Moon will occult, or cover-up, Regulus; this occultation is visible in areas where the eclipse was not visible, including Australia and New Zealand.

Eclipses only occur occasionally (usually around four times a year, with two of these being Lunar Eclipses). A Lunar Eclipse or Eclipse of the Moon occurs only a couple times a year, on average, because the Moon's orbit around the Earth is slightly tilted with respect to Earth's orbit around the Sun. For most months of the year, the Moon passes a little above, or a little below, the Earth's shadow (precluding a Lunar Eclipse).

Of course eclipses, like all celestial observations, are weather-permitting. If the weather in your area does not permit direct viewing outdoors of this Penumbral (partial) Eclipse of the Moon, it can be viewed during a special, live web-cast on the Internet, followed by a live web-cast of Comet 45P / Honda-Mrkos-Pajdusakova as the Comet is about to make its closest approach to Earth since 1983. A link to this web-cast is located at the end of this blog-post.

Other eclipses this year include an Annular Solar Eclipse later this month, on February 26. The other Lunar Eclipse in 2017 is a Partial Lunar Eclipse on August 7. And, this year's eclipses culminate in the middle of Summer with the Great American Total Eclipse of the Sun on August 21, which will follow a path across the United States from Oregon to South Carolina!

Most Native Americans in the Northern Hemisphere referred to the February Full Moon as the Snow Moon for obvious reasons--particularly obvious with yesterday's blizzard in the north-eastern United States. Other Native American tribes have called the February Full Moon the Hunger Moon, due to the difficult hunting conditions during the harsh weather of the month.

While the January Full Moon (and for some tribes the December Full Moon) has been known by some tribes as the Wolf Moon, other tribes referred to the February Full Moon as the Wolf Moon. The Full Moon of February has also been known as the Racoon Moon and the Bare-Spots-on-the-Ground Moon.

In the Southern Hemisphere, the February / Mid-Summer Full Moon has been known as the Grain Moon, Sturgeon Moon, Red Moon, Wyrt Moon, Corn Moon, Dog Moon, and Barley Moon.

Once every 19 years, February has no Full Moon. This is due to the fact that February has only 28 days (29 days once every four years during the Leap Year) while the time duration of the Moon's orbit around the Earth is even shorter: 27.32166 days.

U.S. Naval Observatory Web Page --- Rise / Set Times for Moon and Sun:
Link >>> http://aa.usno.navy.mil/data/docs/RS_OneDay.php

Slooh Community Observatory --- Live, Internet Web-Cast of Feb. 10 Penumbral Lunar Eclipse - Feb. 10, 5:30 p.m. EST / 22:30 UTC; Followed by Live, Internet Web-Cast of
Comet 45P / Honda-Mrkos-Pajdusakova as the Comet is about to make its closest approach to Earth since 1983 - Feb. 10, 10:30 p.m. EST / Feb. 11, 3:30 UTC:
Link >>> http://main.slooh.com/event/the-full-snow-moon-2/

Internet Links to Additional Information ---

Penumbral (partial) Lunar Eclipse of 2017 Feb. 10 to 11:
Link 1 >>> https://eclipse.gsfc.nasa.gov/LEplot/LEplot2001/LE2017Feb11N.pdf
Link 2 >>> http://eclipsewise.com/lunar/LEprime/2001-2100/LE2017Feb11Nprime.html
Link 3 >>> http://earthsky.org/?p=251075

Parts of a Shadow: Umbra, Penumbra, Antumbra:
Link >>> https://en.wikipedia.org/wiki/Umbra%2C_penumbra_and_antumbra

Penumbral Lunar Eclipse: Link >>> https://en.wikipedia.org/wiki/Lunar_eclipse#Penumbral_eclipse

Lunar Eclipse: Link >>> https://en.wikipedia.org/wiki/Lunar_eclipse

Eclipse: Link >>> https://en.wikipedia.org/wiki/Eclipse


Star Regulus: Link >>> https://en.wikipedia.org/wiki/Regulus

Occultation: Link >>> https://en.wikipedia.org/wiki/Occultation

Related Blog Posts ---

"Dim Penumbral Lunar Eclipse Early Wed. Morning." 2016 March 22.

Link >>> http://spacewatchtower.blogspot.com/2016/03/dim-penumbral-lunar-eclipse-early-wed.html

 

"Slight Lunar Eclipse Friday Evening." 2013 Oct. 17.

Link >>> http://spacewatchtower.blogspot.com/2013/10/slight-lunar-eclipse-friday-evening.html?m=0


Source: Glenn A. Walsh Reporting for SpaceWatchtower, a project of Friends of the Zeiss.
             2017 February 10.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >

Wednesday, February 1, 2017

Astronomical Calendar: 2017 February

http://www.mreclipse.com/SEphoto/SEgallery2/image/ASE94Mosaicw.JPG
The last Annular Eclipse of the Sun visible in Western Pennsylvania occurred on
1994 May 10, when the path of annularity passed through Erie County, Pennsylvania,
including the site of the Mercyhurst College Observatory in North East, Pennsylvania.
The above eclipse images were taken in Chrissy, Ohio, just west of Toledo.
(Image Source: ©1994 by Fred Espenak)
This month (on Feb. 26) an Annular Solar Eclipse will occur in the Southern Hemisphere.
More info on this eclipse:
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2017.html#eclipse-sol-ann-2017-2-26
NEVER look directly at a Solar Eclipse or Eclipse of the Sun unless you have the training and proper equipment to do so safely.
SAFE WAY TO VIEW SOLAR ECLIPSE OR ECLIPSE OF THE SUN:
Link >>> http://andrewcarnegie.tripod.com/solflyer2.htm

Astronomical Calendar for 2017 February: 
Link >>> http://buhlplanetarium4.tripod.com/astrocalendar/2017.html#feb

Source: Friends of the Zeiss.
             2017 February 1.

                             Like This Post? - Please Share!

            More Astronomy & Science News - SpaceWatchtower Twitter Feed:
            Link >>> https://twitter.com/spacewatchtower

        Astronomy & Science Links: Link >>> http://buhlplanetarium.tripod.com/#sciencelinks

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

gaw

Glenn A. Walsh, Project Director, Friends of the Zeiss: < http://buhlplanetarium.tripod.com/fotz/ >
& SpaceWatchtower Editor / Author: < http://buhlplanetarium2.tripod.com/weblog/spacewatchtower/gaw/ >
Electronic Mail - < gawalsh@planetarium.cc >
Astronomy Links: < http://buhlplanetarium.tripod.com/#astrolinks >
Science Links: < http://buhlplanetarium.tripod.com/#sciencelinks >
SpaceWatchtower Twitter News Feed: < https://twitter.com/spacewatchtower >
SpaceWatchtower Blog: < http://spacewatchtower.blogspot.com/ >
LibraryWatchtower Blog: < http://librarywatchtower.blogspot.com >
South Hills Backyard Astronomers Blog: < http://shbastronomers.blogspot.com/ >
Barnestormin Blog: Writing, Essays, Pgh. News, etc.: < http://www.barnestormin.blogspot.com/ >
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 >