Globe at Night 2018 Pegasus and Second Sagittarius Campaigns Begin Oct. 1

Summary: The Globe at Night 2018 Pegasus and second Sagittarius campaigns begin Monday, Oct. 1, in the Northern Hemisphere and the Southern Hemisphere, respectively.

The Great Square asterism represents the Winged Horse's main body: EarthSky @earthskyscience via Twitter Nov. 24, 2017

The Globe at Night 2018 Pegasus and second Sagittarius campaigns begin Monday, Oct. 1, and close Wednesday, Oct. 10, as checks of light pollution effects on visibility of Pegasus the Winged Horse constellation in the Northern Hemisphere and on Sagittarius the Archer constellation in the Southern Hemisphere.

The October campaign is the only Globe at Night 2018 campaign for assessing visibility of constellation Pegasus. No 2018 Pegasus campaigns are planned for the Southern Hemisphere. The Winged Horse is visible in the Southern Hemisphere as a winter and spring constellation.

Pegasus the Winged Horse resides in the Northern Celestial Hemisphere, the northern half of the abstract sphere projected by astronomy outward from Earth’s surface. Pegasus lies north of the celestial equator, Earth’s equatorial projection outward onto the abstract celestial sphere.

Pegasus rates as the seventh largest of the 88 modern constellations by area. Sagittarius, Globe at Night’s October Southern Hemisphere constellation campaign, occupies 15th place.

Pegasus associates with Andromeda the Chained Princess, Lacerta the Lizard and Cygnus the Swan as northern neighbors. The Winged Horse’s southern boundary reaches close enough to the celestial equator to claim celestial equator-straddling Pisces the Fishes and Aquarius the Water Bearer as southern neighbors.

Globe at Night’s website suggests autumn as the easiest season for finding Pegasus in the Northern Hemisphere. The Great Square of Pegasus, an asterism depicting the Winged Horse’s main body, is the constellation’s easily recognizable finding aid.

The Great Square of Pegasus gathers together four second magnitude stars from two neighboring constellations. Pegasus provides three stars. Andromeda the Chained Princess contributes one star.

The quadrilateral asterism’s three Pegasus stars rate as second, third and fourth brightest stars, both in the asterism and in constellation Pegasus. Variable red giant Beta Pegasi (β Pegasi; Beta Peg; β Peg) shines as the second brightest star, both in the asterism and in the constellation. Alpha Pegasi (α Pegasi; Alpha Peg; α Peg), known traditionally as Markab, is third brightest. Variable blue-white subgiant Gamma Pegasi (γ Pegasi; Gamma Peg; γ Peg), known traditionally as Algenib (Arabic for “side”), is the fourth brightest star.

Binary star system Alpha Andromedae (α Andromedae; Alpha And; α And) shines as the asterism’s brightest star. Known traditionally as Alpheratz (Arabic for “horse”), Alpha Andromedae is constellation Andromeda’s brightest star.

Globe at Night gives sky views of Pegasus for six Northern Hemisphere locations. For equatorial latitudes, such as Quito, Ecuador, Pegasus perches in the north-northwest. At around 10 degrees north, Pegasus appears in the northwest. At around 20 degrees north latitude, observers find Pegasus in the east. At around 30 degrees north, Pegasus appears in the southeast. Observers at around 40 to 50 degrees north find Pegasus in the south.

Eight magnitude charts present the nighttime sky at six northern latitudes, from equatorial to 50 degrees north. Magnitude zero represents a cloudy sky. Magnitude seven presents a star-filled sky.

At all targeted latitudes, the Winged Horse’s brightest star, Epsilon Pegasi (ε Pegasi; Epsilon Peg, ε Peg), is not visible at magnitude zero but begins visibility as of magnitude one. Epsilon Pegasi’s traditional name, Enif, derived from Arabic for “nose,” recognizes the second-magnitude star’s placement in the Winged Horse’s muzzle (projecting part of the face).

Closing of Globe at Night’s only 2018 Pegasus campaign leaves only two campaigns on Globe at Night’s 2018 Northern Hemisphere schedule. Perseus the Hero’s two campaigns run from Tuesday, Oct. 30, to Thursday, Nov. 8, and from Thursday, Nov. 29, to Saturday, Dec. 8.

Globe at Night’s second 2018 Sagittarius campaign in the Southern Hemisphere coincides with the Northern Hemisphere’s only 2018 Pegasus campaign. The year’s first Sagittarius campaign ran from Saturday, Sept. 1, through Monday, Sept. 10.

Globe at Night’s website suggests the Milky Way as finding aid for Sagittarius the Archer constellation. The Archer’s distinctive eight-star asterism, the Teapot, spouts Milky Way steam.

Completion of Globe at Night’s second 2018 Sagittarius campaign leaves only two 2018 Grus the Crane constellation campaigns on Globe at Night’s 2018 Southern Hemisphere schedule. The first 2018 Grus campaign begins Tuesday, Oct. 30, and closes Thursday, Nov. 8. The second 2018 Grus campaign runs from Thursday, Nov. 29, to Saturday, Dec. 8.

The takeaway for the Globe at Night 2018 Pegasus and second Sagittarius campaigns, conducted from Monday, Oct. 1, through Wednesday, Oct. 10, is that the Northern Hemisphere’s Pegasus campaign opens as the only 2018 Winged Horse campaign while the Southern Hemisphere’s Sagittarius campaign closes as the second of two 2018 Archer campaigns.

Sagittarius the Archer is a Milky Way constellation with a distinctive Teapot asterism: NASA, ESA, Z. (Zoltan G.) Levay (STScI [Space Telescope Science Institute]) and A. (Akira) Fujii, Public Domain, via Wikimedia Commons

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Pegasus the Winged Horse’s noticeable asterism, the Great Square, serves as the constellation’s perfect finding aid: EarthSky @earthskyscience via Twitter Sept. 16, 2017, @ https://twitter.com/earthskyscience/status/909207549282537472

Sagittarius the Archer is a Milky Way constellation with a distinctive Teapot asterism: NASA, ESA, Z. (Zoltan G.) Levay (STScI [Space Telescope Science Institute]) and A. (Akira) Fujii, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:HST_SWEEPS_Galaxy_Location-2006.jpg

For further information:

“Can You Find Pegasus?” Globe at Night > Finding Constellations.
Available @ https://www.globeatnight.org/finding/pegasus

“Can You Find Sagittarius?” Globe at Night > Finding Constellations.
Available @ https://www.globeatnight.org/finding/sagittarius

EarthSky @earthskyscience. “How to see the Great Square of Pegasus. 4 stars of nearly equal brightness in a large square pattern.” Twitter. Sept. 16, 2017.
Available @ https://twitter.com/earthskyscience/status/909207549282537472

EarthSky @earthskyscience. “How to see the Great Square of Pegasus. It’s easy! The Great Square of Pegasus consists of 4 stars of nearly equal brightness in a large square pattern. Once you find it, you can star-hop to other well-known sights in the sky.” Twitter. Nov. 24, 2017.
Available @ https://twitter.com/earthskyscience/status/934121193170448385

EarthSky ‏@earthskyscience. “It can be hard to see a Centaur in constellation Sagittarius. But The Teapot is easy to make out. . . Photo: Zefri Besar.” Twitter. Oct. 14, 2016.
Available @ https://twitter.com/earthskyscience/status/787081309738954753

Learn to Skywatch @Learntoskywatch. “Tonight’s Target: The Constellation Pisces. Hint: Look SE below the Great Square of Pegasus.” Twitter. Sept. 21, 2017.
Available @ https://twitter.com/Learntoskywatch/status/910926632000598016

Marriner, Derdriu. “Alpheratz Links Adromeda the Chained Princess With Pegasus the Winged Horse.” Earth and Space News. Wednesday, Nov. 1, 2017.
Available @ https://earth-and-space-news.blogspot.com/2016/10/northern-cross-marks-autumn-nights-from.html

Marriner, Derdriu. “Five Star Circlet of Pisces Asterism Is Below Great Square of Pegasus.” Earth and Space News. Wednesday, Oct. 11, 2017.
Available @ https://earth-and-space-news.blogspot.com/2017/10/five-star-circlet-of-pisces-asterism-is.html

Marriner, Derdriu. “Globe at Night 2018 Bootes and Crux Campaigns Happen in May.” Earth and Space News. Wednesday, May 9, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/05/globe-at-night-2018-bootes-and-crux.html

Marriner, Derdriu. “Globe at Night 2018 Cygnus and Second Scorpius Campaigns Begin Aug. 2.” Earth and Space News. Wednesday, Aug. 1, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/08/globe-at-night-2018-cygnus-and-second.html

Marriner, Derdriu. “Globe at Night 2018 Hercules and Third Crux Campaigns Begin June 4.” Earth and Space News. Wednesday, May 30, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/05/globe-at-night-2018-hercules-and-third.html

Marriner, Derdriu. “Globe at Night 2018 Leo Campaign Begins April 6 for Northern Latitudes.” Earth and Space News. Wednesday, April 4, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/04/globe-at-night-2018-leo-campaign-begins.html

Marriner, Derdriu. “Globe at Night 2018 Sagittarius and Second Cygnus Campaigns Begin Sept. 1.” Earth and Space News. Wednesday, Aug. 22, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/08/globe-at-night-2018-sagittarius-and.html

Marriner, Derdriu. “Globe at Night 2018 Scorpius and Second Hercules Campaigns Begin July 4.” Earth and Space News. Wednesday, June 27, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/06/globe-at-night-2018-scorpius-and-second.html

Marriner, Derdriu. “Great Square of Pegasus Asterism Has Four Second Magnitude Stars.” Earth and Space News. Wednesday, Oct. 4, 2017.
Available @ https://earth-and-space-news.blogspot.com/2017/10/great-square-of-pegasus-asterism-has.html