The constellation Vulpecula as it can be seen by the naked eye
[https://en.wikipedia.org/wiki/Vulpecula]
Vulpecula
[https://www.iau.org/public/images/detail/vul/]
Vulpecula constellation lies in the northern sky. Its name means ‘the little fox’ in Latin. It is not associated with any myths. Vulpecula is the 55th constellation in size, occupying an area of 268 square degrees. It is located in the fourth quadrant of the northern hemisphere (NQ4) and can be seen at latitudes between +90° and -55°. The neighboring constellations are Cygnus, Delphinus, Hercules, Lyra, Pegasus and Sagitta.
[http://www.constellation-guide.com/constellation-list/vulpecula-constellation/]
The fox and the goose shown as ‘Vulpec. & Anser’ on the Atlas Coelestis of John Flamsteed (1729).
Vulpecula is a constellation introduced in 1687 by the Polish astronomer Johannes Hevelius, who depicted it as a double figure of a fox, Vulpecula, carrying in its jaws a goose, spelt both as Anser and Ansere. Since then the goose has flown (or been eaten), leaving just the fox. Hevelius placed the fox near two other hunting animals, the eagle (the constellation Aquila) and the vulture (which was an alternative identification for Lyra). He explained that the fox was taking the goose to neighbouring Cerberus, another of his inventions- although this part of the tableau has been spoilt, as Cerberus is now obsolete.
Hevelius himself was somewhat inconsistent in his naming of this constellation. In his star catalogue he named the pair ‘Vulpecula cum Ansere,’ the fox with goose, but showed them separately as ‘Anser’ and ‘Vulpecula’ on his Firmamentum Sobiescianum star atlas. Others preferred the slightly amended title fox and goose.
[http://www.ianridpath.com/startales/vulpecula.htm]
Vulpecula
[http://astropixels.com/constellations/charts/Vul.html]
Vulpecula - September 15, 10:00 PM - Latitude 45° North, Longitude 95° West
[http://www.peoplesguidetothecosmos.com/constellations/vulpecula.htm]
Amateur image of dark nebula LDN 778 (center) and Alpha Vulpeculae, (red giant, top center).
Alpha Vulpeculae, also named Anser, is the brightest star in the constellation of Vulpecula. It is approximately 297 light-years from Earth. It forms a wide optical binary with 8 Vulpeculae. It is a red giant of spectral class M1 and has apparent magnitude +4.4. It bore the traditional name Anser, derived from when the constellation had the name Vulpecula cum Ansere ‘the little fox with the goose.’
[https://en.wikipedia.org/wiki/Alpha_Vulpeculae]
23 Vulpeculae (second brightest) is a class K3III (orange giant) star in a triple star system. Its apparent magnitude is 4.52 and it is approximately 339 light years away based on parallax. It has two reported companions.
[https://en.wikipedia.org/wiki/23_Vulpeculae]
31 Vulpeculae (third brightest) is a class G7III (yellow giant) star. Its apparent magnitude is 4.56 and it is approximately 189 light years away. It is a suspected variable star, and also a spectroscopic binary with a period of about 5 years.
[https://en.wikipedia.org/wiki/31_Vulpeculae]
HD 189733 is a Sun- like star in Vulpecula with a hot- Jupiter (HD 189733b):
Exoplanet HD 189733b
This graphic depicts HD 189733b, the first exoplanet caught passing in front of its parent star in X-rays. As described in our press release , NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM Newton Observatory have been used to observe a dip in X-ray intensity as HD 189733b transits its parent star.
The main figure is an artist’s impression showing the HD 189733 system, containing a Sun-like star orbited by HD 189733b, an exoplanet about the size of Jupiter. This “hot Jupiter” is over 30 times closer to its star than Earth is to the Sun and goes around the star once every 2.2 days, as determined from previous observations. Also in the illustration is a faint red companion star, which was detected for the first time in X-rays with these observations. This star orbits the main star about once every 3,200 years.
The inset contains the Chandra image of HD 189733. The source in the middle is the main star and the source in the lower right is the faint companion star. The source at the bottom of the image is a background object not contained in the HD 189733 system.
The exoplanet itself cannot be seen in the Chandra image, as the transits involve measuring small decreases in X-ray emission from the main star. The authors estimate that the percentage decrease in X-ray light during the transits is about three times greater than the corresponding decrease in optical light. This tells them that the region blocking X-rays from the star is substantially larger than the region blocking optical light from the star, helping to determine the size of the planet's atmosphere. The extended atmosphere implied by these results is shown by the light blue color around the planet. Recent observations of HD 189733b with the Hubble Space Telescope have confirmed that the lower atmosphere of the planet has a deep blue color, due to the preferential scattering of blue light by silicate particles in its atmosphere.
For about a decade astronomers have known that ultraviolet and X-ray radiation from the main star in HD 189733 are evaporating the atmosphere of its closely orbiting planet over time. The authors of the new study estimate that HD 189733b is losing between 100 million and 600 million kilograms per second. This rate is about 25% to 65% higher than it would be if the planet's atmosphere were not extended.
At a distance of just 63 light years, HD 189733b is the closest hot Jupiter to Earth, which makes it a prime target for astronomers who want to learn more about this type of exoplanet and the atmosphere around it.
Chandra was used to make observations of six transits by HD 189733b and the team also used archival data from XMM-Newton for one transit. These results are available online and will appear in the August 10th issue of The Astrophysical Journal.
[https://www.nasa.gov/mission_pages/chandra/multimedia/exoplanet-hd-189733b.html]
Vulpecula OB1 is a stellar association of newborn giant stars:
The Little Fox and the Giant Stars
New stars are the lifeblood of our galaxy, and there is enough material revealed by this Herschel infrared image to build stars for millions of years to come.
Situated 8,000 light-years away in the constellation Vulpecula- Latin for ‘little fox’- the region in the image is known as Vulpecula OB1. It is a ‘stellar association’ in which a batch of truly giant ‘OB’ stars is being born. O and B stars are the largest stars that can form.
The giant stars at the heart of Vulpecula OB1 are some of the biggest in the galaxy. Containing dozens of times the mass of the sun, they have short lives, astronomically speaking, because they burn their fuel so quickly. At an estimated age of 2 million years, they are already well through their lifespans. When their fuel runs out, they will collapse and explode as supernovas. The shock this will send through the surrounding cloud will trigger the birth of even more stars, and the cycle will begin again.
O- stars are at least 16 times more massive than the sun, and could be well over 100 times as massive. They are anywhere from 30,000 to 1 million times brighter than the sun, but they only live up to a few million years before exploding. B-stars are between two and 16 times as massive as the sun. They can range from 25 to 30,000 times brighter than the sun.
OB associations are regions with collections of O and B stars. Since OB stars have such short lives, finding them in large numbers indicates the region must be a strong site of ongoing star formation, which will include many more smaller stars that will survive far longer.
The vast quantities of ultraviolet light and other radiation emitted by these stars is compressing the surrounding cloud, causing nearby regions of dust and gas to begin the collapse into more new stars. In time, this process will ‘eat’ its way through the cloud, transforming some of the raw material into shining new stars.
The image was obtained as part of Herschel’s Hi-GAL key-project. This used the infrared space observatory’s instruments to image the entire galactic plane in five different infrared wavelengths.
These wavelengths reveal cold material, most of it between -220º C and -260º C. None of it can be seen in ordinary optical wavelengths, but this infrared view shows astronomers a surprising amount of structure in the cloud’s interior.
The surprise is that the Hi-GAL survey has revealed a spider’s web of filaments that stretches across the star-forming regions of our galaxy. Part of this vast network can be seen in this image as a filigree of red and orange threads.
In visual wavelengths, the OB association is linked to a star cluster catalogued as NGC 6823. It was discovered by William Herschel in 1785 and contains 50 to 100 stars. A nebula emitting visible light, catalogued as NGC 6820, is also part of this multi-faceted star-forming region.
[https://www.nasa.gov/image-feature/jpl/pia13500/the-little-fox-and-the-giant-stars]
M27 is a nebula in Vulpecula, also known as The Dumbbell Nebula:
M27: The Dumbbell Nebula
The first hint of what will become of our Sun was discovered inadvertently in 1764. At that time, Charles Messier was compiling a list of diffuse objects not to be confused with comets. The 27th object on Messier’s list, now known as M27 or the Dumbbell Nebula, is a planetary nebula, the type of nebula our Sun will produce when nuclear fusion stops in its core. M27 is one of the brightest planetary nebulae on the sky, and can be seen toward the constellation of the Fox (Vulpecula) with binoculars. It takes light about 1000 years to reach us from M27, shown above in colors emitted by hydrogen and oxygen. Understanding the physics and significance of M27 was well beyond 18th century science. Even today, many things remain mysterious about bipolar planetary nebula like M27, including the physical mechanism that expels a low-mass star’s gaseous outer-envelope, leaving an X-ray hot white dwarf.
[http://apod.nasa.gov/apod/ap140914.html]
Collinder 399 (The Coat Hanger) is an asterism in Vulpecula:
Collinder 399: The Coat Hanger
Is this coat hanger a star cluster or an asterism? This cosmic hang-up has been debated over much of last century, as astronomers wondered whether this binocular-visible object is really a physically associated open cluster or a chance projection. Chance star projections are known as asterisms, an example of which is the popular Big Dipper. Recent precise measurements from different vantage points in the Earth’s orbit around the Sun have uncovered discrepant angular shifts indicating that the Coat Hanger is better described as an asterism. Known more formally as Collinder 399, this bright stellar grouping is wider than the full moon and lies in the constellation of the Fox (Vulpecula). On the far right of the image is the open cluster of stars NGC 6802.
[https://apod.nasa.gov/apod/ap081223.html]
This is the open cluster NGC 6802 in Vulpecula:
Open Star Cluster NGC 6802 in Vulpecula
The field of view is about 9x9 arc minutes, with North at the top. This image was taken under a full moon. The image is a 10 minute black & white exposure taken under dark sky.
[http://www.kopernik.org/images/archive/n6802.htm]
NGC 6820 and NGC 6823 are a reflection nebula and an open cluster, respectively, in Vulpecula:
Emission nebula NGC6820 with open cluster NGC6823
NGC 6820 is a small reflection nebula near the open cluster NGC 6823 in Vulpecula. The reflection nebula and cluster are embedded in a large faint emission nebula called Sh 2-86. The whole area of nebulosity is often referred to as NGC 6820. M27, the Dumbbell Nebula, is found three degrees to the east, and α Vulpeculae three degrees to the west. Open star cluster NGC 6823 is about 50 light years across and lies about 6000 light years away. The center of the cluster formed about two million years ago and is dominated in brightness by a host of bright young blue stars. Outer parts of the cluster contain even younger stars. It forms the core of the Vulpecula OB1 stellar association.
[https://en.wikipedia.org/wiki/NGC_6820_and_NGC_6823]
NGC 7052 is an edge-on spiral galaxy in Vulpecula at a distance of 214 million light-years from Earth:
Disk around a Black Hole in Galaxy NGC 7052
Resembling a gigantic hubcap in space, a 3,700 light-year-diameter dust disk encircles a 300 million solar-mass black hole in the center of the elliptical galaxy NGC 7052. The disk, possibly a remnant of an ancient galaxy collision, will be swallowed up by the black hole in several billion years. Because the front end of the disk eclipses more stars than the back, it appears darker. Also, because dust absorbs blue light more effectively than red light, the disk is redder than the rest of the galaxy (this same phenomenon causes the Sun to appear red when it sets in a smoggy afternoon).
[https://www.spacetelescope.org/images/opo9822a/]
Planetary nebula Hen 2-437 is also located in the constellation of Vulpecula:
Hubble watches the icy blue wings of Hen 2-437
In this cosmic snapshot, the spectacularly symmetrical wings of Hen 2-437 show up in a magnificent icy blue hue. Hen 2-437 is a planetary nebula, one of around 3,000 such objects known to reside within the Milky Way.
Located within the faint northern constellation of Vulpecula (The Fox), Hen 2-437 was first identified in 1946 by Rudolph Minkowski, who later also discovered the famous and equally beautiful M2-9 (otherwise known as the Twin Jet Nebula). Hen 2-437 was added to a catalog of planetary nebula over two decades later by astronomer and NASA astronaut Karl Gordon Henize.
Planetary nebulae such as Hen 2-437 form when an aging low-mass star- such as the sun- reaches the final stages of life. The star swells to become a red giant, before casting off its gaseous outer layers into space. The star itself then slowly shrinks to form a white dwarf, while the expelled gas is slowly compressed and pushed outwards by stellar winds. As shown by its remarkably beautiful appearance, Hen 2-437 is a bipolar nebula- the material ejected by the dying star has streamed out into space to create the two icy blue lobes pictured here.
[https://www.nasa.gov/image-feature/goddard/2016/hubble-watches-the-icy-blue-wings-of-hen-2-437]
Abell 68 is a distant cluster of galaxies toward Vulpecula:
Looking Through Abell 68
Want to use a cluster of galaxies as a telescope? It’s easier than you might think as distant galaxy clusters naturally act as strong gravitational lenses. In accordance with Einstein’s theory of general relativity, the cluster gravitational mass, dominated by dark matter, bends light and creates magnified, distorted images of even more distant background galaxies. This sharp infrared Hubble image illustrates the case for galaxy cluster Abell 68 as a gravitational telescope, explored by amateur astronomer Nick Rose during the ESA-Hubble Hidden Treasures image processing competition. Putting your cursor over the picture will label highlights in the scene. Labels 1 and 2 show two lensed images of the same background galaxy. The distorted galaxy image labeled 2 resembles a vintage space invader! Label 3 marks a cluster member galaxy, not gravitationally lensed, stripped of its own gas as it plows through the denser intergalactic medium. Label 4 includes many background galaxies imaged as elongated streaks and arcs. Abell 68 itself is some 2.1 billion light-years distant toward the constellation Vulpecula. The central region of the cluster covered in the Hubble view spans over 1.2 million light-years.
[https://apod.nasa.gov/apod/ap130308.html]
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