Lyra

Lyra (Latin for lyre, from Greek λύρα) is a small constellation. It is one of 48 listed by the 2nd century astronomer Ptolemy, and is one of the 88 constellations recognized by the International Astronomical Union. Lyra was often represented on star maps as a vulture or an eagle carrying a lyre, and hence sometimes referred to as Aquila Cadens or Vultur Cadens. Beginning at the north, Lyra is bordered by Draco, Hercules, Vulpecula, and Cygnus. Lyra is visible from the northern hemisphere from spring through autumn, and nearly overhead, in temperate latitudes, during the summer months. From the southern hemisphere, it is visible low in the northern sky during the winter months. Covering 286.5 square degrees, it ranks 52nd of the 88 modern constellations in size.

Lyra was frequently visualized as an eagle or vulture as well as a lyre; both are shown on this engraving from the Uranographia of Johann Bode (1801). Near the tip of the vulture’s beak is the bright star Vega, here spelt Wega; Bode also gave it the alternative name Testa in reference to the tortoise shell from which the lyre was supposedly made by Hermes.

[http://www.ianridpath.com/startales/lyra.htm]

In Greek mythology, Lyra represents the lyre of Orpheus. Made by Apollo from a tortoise shell, it was said to be the first lyre ever produced. Orpheus’s music was said to be so great that even inanimate objects such as trees, streams, and rocks could be charmed. Joining Jason and the Argonauts, his music was able to quell the voices of the dangerous Sirens, who sang tempting songs to the Argonauts.

At one point, Orpheus married Eurydice, a nymph. While fleeing from an attack by Aristaeus, she stepped on a snake that bit her, killing her. To reclaim her, Orpheus entered the Underworld, where the music from his lyre charmed Hades. Hades relented and let Orpheus bring Eurydice back, on the condition that he never once look back until outside. Unfortunately, near the very end, Orpheus faltered and looked back, causing Eurydice to be left in the Underworld forever. Orpheus spent the rest of his life strumming his lyre while wandering aimlessly through the land, rejecting all marriage offers from women.

There are two competing myths relating to the death of Orpheus. According to Eratosthenes, Orpheus failed to make a necessary sacrifice to Dionysus due to his regard for Apollo as the supreme deity instead. Dionysus then sent his followers to rip Orpheus apart. Ovid tells a rather different story, saying that women, in retribution for Orpheus's rejection of marriage offers, ganged up and threw stones and spears. At first, his music charmed them as well, but eventually their numbers and clamor overwhelmed his music and he was hit by the spears. Both myths then state that his lyre was placed in the sky by the muses.

Vega and its surrounding stars are also treated as a constellation in other cultures. The area corresponding to Lyra was seen by the Arabs as a vulture or an eagle carrying a lyre, either enclosed in its wings, or in its beak. In Wales, Lyra is known as King Arthur’s Harp (Talyn Arthur), and King David’s harp. The Persian poet Hafiz called it the Lyre of Zurah. In Australian Aboriginal astronomy, Lyra is known by the Boorong people in Victoria as the Malleefowl constellation. Lyra was known as Urcuchillay by the Incas and was worshipped as an animal deity.

In Chinese astronomy Lyra is located within the northern quadrant of the sky, which is symbolized as the Black Tortoise of the North (Běi Fāng Xuán Wǔ). The name of the western constellation in modern Chinese is (tiān qín zuò), meaning ‘the celestial zither constellation.’

[https://en.wikipedia.org/wiki/Lyra_%28Chinese_astronomy%29]

[https://thecuriousastronomer.wordpress.com/tag/galilean-moons/]

The Summer Triangle, and the globular cluster M13 in Hercules, as seen at 10 p.m. on July 20

[http://oneminuteastronomer.com/4253/easy-summer-stargazing/]

This shot is of the Summer Triangle. Brilliant Vega in Lyra is at the top of the frame. Deneb in Cygnus is at lower left. Altair in Aquila is at lower right. The rich star clouds and dark nebulas of the Milky Way in Cygnus dominate the image. The Great Rift runs through the star clouds above Aquila through Cygnus in the center of the frame. Le Gentil 3, a large dark nebula, is to the left of Deneb. The North America Nebula is just below Deneb. Brocchi’s Cluster, also known as the ‘Coathanger’ is also visible in Vulpecula.

[http://www.astropix.com/HTML/BEGINNER/Summer_Triangle.HTM]

Vega through Celestron

Vega (Alpha Lyrae) is the brightest star in the constellation Lyra, the fifth brightest star in the night sky and the second brightest star in the northern celestial hemisphere, after Arcturus. It is a relatively close star at only 25 light-years from Earth, and, together with Arcturus and Sirius, one of the most luminous stars in the Sun’s neighborhood.

The traditional name Vega comes from a loose transliteration of the Arabic word ‘wāqi,’ meaning ‘falling’ or ‘landing,’ via the phrase ‘an-nasr al-wāqi,’ ‘the falling eagle.’

Vega has been extensively studied by astronomers, leading it to be termed the next most important star in the sky after the Sun. It was the northern pole star around 12,000 BCE and will be so again around the year 13,727 when the declination will be +86°14'. It was the first star other than the Sun to be photographed and the first to have its spectrum recorded. It was one of the first stars whose distance was estimated through parallax measurements.

Vega’s spectral class is A0V, making it a blue-tinged white main sequence star that is fusing hydrogen to helium in its core. Since more massive stars use their fusion fuel more quickly than smaller ones, Vega’s main-sequence lifetime is roughly one billion years, a tenth of the Sun’s. The current age of this star is about 455 million years, or up to about half its expected total main-sequence lifespan. After leaving the main sequence, Vega will become a class-M red giant and shed much of its mass, finally becoming a white dwarf. At present, Vega has more than twice the mass of the Sun and its full luminosity is about 40 times the Sun’s value. However, because of its high rate of rotation, the pole is considerably brighter than the equator. Because it is seen nearly pole-on, its apparent luminosity from Earth is notably higher, about 57 times the Sun’s value.

Size comparison of Vega (left) to the Sun (right)

The pole of Vega- its axis of rotation- is inclined no more than five degrees from the line-of-sight to the Earth. At the high end of estimates for the rotation velocity for Vega is 236.2 ± 3.7 km/s along the equator, which is 87.6% of the speed that would cause the star to start breaking up from centrifugal effects. This rapid rotation of Vega produces a pronounced equatorial bulge, so the radius of the equator is 19% larger than the polar radius. The estimated polar radius of this star is about 2.362 solar radii, while the equatorial radius is about 2.818 solar radii. From the Earth, this bulge is being viewed from the direction of its pole, producing the overly large radius estimate.

Based on an observed excess emission of infrared radiation, Vega appears to have a circumstellar disk of dust. This dust is likely to be the result of collisions between objects in an orbiting debris disk, which is analogous to the Kuiper belt in the Solar System. Stars that display an infrared excess because of dust emission are termed Vega-like stars.

[https://en.wikipedia.org/wiki/Vega]

Besides the Summer Triangle asterism, Vega also forms one vertex of a much smaller triangle, along with Epsilon and Zeta Lyrae. Zeta forms a wide binary star visible in binoculars, consisting of an Am star and an F-type subgiant. The Am star has an additional close companion, bringing the total number of stars in the system to three.

Epsilon is a more famous wide binary that can even be separated by the naked eye under good conditions. Both components are themselves close binaries which can be seen with telescopes to consist of A- and F-type stars, and a faint star was recently found to orbit component C as well, for a total of five stars.

In contrast to Zeta and Epsilon Lyrae, Delta Lyrae is an optical double, with the two stars simply lying along the same line of sight east of Zeta. The brighter and closer of the two, Delta2 Lyrae, is a 4th-magnitude red bright giant that varies semiregularly by around 0.2 magnitudes with a dominant period of 79 days, while the fainter Delta1 Lyrae is a spectroscopic binary consisting of a B-type primary and an unknown secondary. Both systems, however, have very similar radial velocities, and are the two brightest members of a sparse open cluster known as the Delta Lyrae cluster.

Sulafat (Gamma Lyrae) (Apr 15, 2004)

[http://www.nikomi.net/english/art/photo/astro/stars/sulafat.htm]

South of Delta is Gamma Lyrae, a blue giant and the second-brightest star in the constellation. With an apparent visual magnitude of 3.3, it is readily visible to the naked eye. Its estimated distance is 620 light-years (190 parsecs) from the Sun. The traditional name Sulafat (Sulaphat) is Arabic for ‘turtle.’ The connection with turtles is that fine harps were traditionally made of tortoiseshell.

This is a giant star with a stellar classification of B9 III, indicating it has exhausted the supply of hydrogen at its core and evolved away from the main sequence. The effective temperature of the outer envelope of this star is 10,080 K, giving it the blue-white hue typical of a B-type star. The interferometry-measured angular diameter of this star is 0.74 ± 0.10 mas, which, at its estimated distance, equates to a physical radius of roughly 15 times the radius of the Sun.

[https://en.wikipedia.org/wiki/Gamma_Lyrae]

The final star forming the lyre’s figure is Beta Lyrae, also a binary composed of a blue bright giant and an early B-type star. In this case, the stars are so close together that the larger giant is overflowing its Roche lobe and transferring material to the secondary, forming a semidetached system. The secondary, originally the less massive of the two, has accreted so much mass that it is now substantially more massive, albeit smaller, than the primary, and is surrounded by a thick accretion disk. The plane of the orbit is aligned with Earth and the system thus shows eclipses, dropping nearly a full magnitude from its 3rd-magnitude baseline every 13 days, although its period is increasing by around 19 seconds per year. It is the prototype of the Beta Lyrae variables, eclipsing semidetached binaries of early spectral types in which there are no exact onsets of eclipses, but rather continuous changes in brightness.

R Lyrae near Vega

Another easy-to-spot variable is the bright R Lyrae, north of the main asterism. Also known as 13 Lyrae, it is a 4th magnitude semiregular variable star, approximately 350 light years away from Earth. It is a red giant star of the spectral type M5III, meaning it has a surface temperature of under 3,500 kelvins. It is much larger and brighter, yet cooler, than the Sun. In the near-infrared J band, it is brighter than the nearby Vega.

R Lyrae is unusual in that it is a red star with a high proper motion, greater than 50 milliarcseconds a year. The variability is not consistent and regular, but periods of 46, 64, 378, and 1,000 days have been reported, with the 46-day period being the strongest. It is calculated that R Lyrae was a 2.0 M☉ star on the main sequence. It is considered an oxygen-rich asymptotic giant branch star, with both hydrogen and helium shells fusing.

[https://en.wikipedia.org/wiki/R_Lyrae]

The RR Lyrae variable stars fall in a particular area on a Hertzsprung–Russell diagram of color versus brightness.

In the extreme east of the constellation is RR Lyrae, the prototype of the large class of variables known as RR Lyrae variables, which are pulsating variables similar to Cepheids, but are evolved population II stars of spectral types A and F. Such stars are usually not found in a galaxy’s thin disk, but rather in the galactic halo. Such stars serve as standard candles, and thus are a reliable way to calculate distances to the globular clusters in which they reside. RR Lyrae itself varies between magnitudes 7 and 8.
[https://en.wikipedia.org/wiki/RR_Lyrae_variable]

Discovery image of Gliese 758 b, taken with Subaru HiCIAO in the near infrared

Gliese 758 is a Sun-like star located 51.4 light-years (15.8 parsecs) from Earth. At about magnitude 6 it is a challenge to view with the naked eye even in good seeing conditions, but can be easily seen through a small telescope or binoculars. It has 97% of the Sun’s mass and 88% of the radius of the Sun. The spectrum matches a stellar classification of G8V, identifying it as a G-type main sequence star that is generating energy through the nuclear fusion of hydrogen at its core. It is radiating this energy into space from its outer envelope at an effective temperature of 5425 K. Estimates of its age put it at about 7.7–8.7 billion years old, although some measurements give it an age as low as 720 million years. The abundance of elements other than hydrogen and helium, what astronomers term the star’s metallicity, are 51% higher than in the Sun.

In November 2009, a team using the HiCIAO instrument of the Subaru Telescope imaged a substellar companion orbiting the star. This object, designated Gliese 758 B, was estimated to be of approximately 10-40 Jupiter masses. A second candidate object was also detected, which was given the designation Gliese 758 C. Follow-up studies of the system suggested the mass range of Gliese 758 b, indicating it to be a companion with approximately 30 to 40 Jupiter masses and revealed that Gliese 758 C is a background star which is not physically associated with the Gliese 758 system. On the other hand, a younger age was suggested from the kinematic stellar grouping.

[https://en.wikipedia.org/wiki/Gliese_758]

Lyra is one of three constellations (along with neighboring Cygnus and Draco) to be in the Kepler Mission’s field of view, and as such it contains many more known exoplanets than most constellations. In April 2013, it was announced that of the five planets orbiting the star Kepler-62, at least two- Kepler-62e and Kepler-62f- are within the boundaries of the habitable zone of that star, where scientists think liquid water could exist, and are both candidates for being a solid, rocky, earth-like planet. The exoplanets are 1.6 and 1.4 times the diameter of Earth respectively, with their star Kepler-62 at a distance of 1,200 light-years:

Kepler-62 and the Solar System

The diagram compares the planets of the inner solar system to Kepler-62, a five-planet system about 1,200 light-years from Earth in the constellation Lyra. The five planets of Kepler-62 orbit a star classified as a K2 dwarf, measuring just two thirds the size of the sun and only one fifth as bright. At seven billion years old, the star is somewhat older than the sun.

Much like our solar system, Kepler-62 is home to two habitable zone worlds, Kepler-62f and Kepler-62e. Kepler-62f orbits every 267 days and is only 40 percent larger than Earth, making it the smallest exoplanet known in the habitable zone of another star. The other habitable zone planet, Kepler-62e, orbits every 122 days and is roughly 60 percent larger than Earth.

The size of Kepler-62f is known, but its mass and composition are not. However, based on previous exoplanet discoveries of similar size that are rocky, scientists are able to determine its mass by association.

The two habitable zone worlds orbiting Kepler-62 have three interior companions, two larger than the size of Earth and one about the size of Mars. Kepler-62b, Kepler-62c and Kepler-62d, orbit every five, 12, and 18 days, respectively, making them very hot and inhospitable for life as we know it.

[https://www.nasa.gov/content/kepler-62-and-the-solar-system]

Line up comparing the Kepler-37 planets system to the moon and planets in the Solar System

Kepler-37 is a G-type main-sequence star located 215.2 light years from Earth in the constellation Lyra. It is host to exoplanets Kepler-37b, Kepler-37c, Kepler-37d and Kepler-37e, all of which orbit very close to it. Kepler-37 has a mass about 80.3 percent of the Sun’s and a radius about 77 percent as large. It has a temperature similar to that of the Sun, but a bit cooler at 5,417 K. It has about half the metallicity of our Sun. With an age of roughly 6 billion years, it is slightly older than the Sun, but is still a main-sequence star.

Kepler-37b is the closest planet to the Kepler-37. At the time of its discovery in February 2013, it was the smallest known exoplanet. At 3,865 kilometres (2,402 mi) in diameter, it is slightly larger than the Moon. It orbits Kepler-37 once every 13 days at a distance of about 0.1 astronomical units (AU). Kepler-37b has a rocky surface and is believed to be too small and too close to its star to support water or maintain an atmosphere. Surface temperature is estimated at 700 K (427 °C; 800 °F).

Kepler-37c is around three-quarters of the diameter of Earth and orbits approximately every 21 days at a distance of just under 0.14 AU. Kepler-37d is about twice the diameter of Earth. It orbits in around 40 days at a distance of nearly 0.21 AU. Neither is able to support water due to their proximity to Kepler-37.

[https://en.wikipedia.org/wiki/Kepler-37]

Size comparison of Kepler-20e and Kepler-20f (artist’s impressions) with Venus and Earth (actual photographs)

Kepler-20 is a star 950 light-years from Earth in the constellation Lyra with a system of five known planets. The apparent magnitude of this star is 12.51, so it cannot be seen with the unaided eye. Viewing it requires a telescope with an aperture of 15 cm (6 in) or more. It is slightly smaller than the Sun, with 94% of the Sun’s radius and about 91% of the Sun’s mass. The effective temperature of the photosphere is slightly cooler than that of the Sun at 5466 K, giving it the characteristic yellow hue of a stellar class G8 star. The abundance of elements other than hydrogen or helium, what astronomers term the metallicity, is approximately the same as in the Sun. It may be older than the Sun, although the margin of error here is relatively large.

On December 20, 2011, the Kepler Space Telescope team reported the discovery of a five-planet system containing three small gas giants and the first two Earth-sized extrasolar planets, Kepler-20e (the first known extrasolar planet smaller than Earth orbiting a main-sequence star) and Kepler-20f, orbiting a Sun-like star. Although the planets are Earth-sized, they are not Earth-like in the respect that they are much closer to their star than Earth, and are hence not near the habitable zone, with expected surface temperatures of 760 °C (1,400 °F) and 427 °C (801 °F), respectively. The three other Neptune-sized planets in the system, Kepler-20b, Kepler-20c, and Kepler-20d, all orbit similarly close to the star. Kepler-20g is a non-transiting exoplanet orbiting Kepler-20.

The masses of e and f are expected masses. Their masses are uncertain as they are too small to detect via radial velocity with current technology.

All planets are at small near resonances; proceeding outwards, they are 3:2, 4:2, 2:1, 4:1.

[https://en.wikipedia.org/wiki/Kepler-20]

Kepler-444: An Ancient System with Five Planets

[https://www.nasa.gov/ames/kepler/kepler-444-an-ancient-system-with-five-planets]

Kepler-444 is a star, estimated to be 11.2 billion years old (more than 80% of the age of the universe), approximately 117 light-years (36 pc) away from Earth in the constellation Lyra. On 27 January 2015, the Kepler spacecraft is reported to have confirmed the detection of five sub-Earth-sized rocky exoplanets orbiting the star. According to NASA, no life as we know it could exist on these hot exoplanets, due to their close orbital distances to the host star.

The original research on Kepler-444 was published in The Astrophysical Journal on 27 January 2015 under the title ‘An ancient extrasolar system with five sub-Earth-size planets’ by a team of 40 authors, the abstract reads as follows:

“The chemical composition of stars hosting small exoplanets (with radii less than four Earth radii) appears to be more diverse than that of gas-giant hosts, which tend to be metal-rich. This implies that small, including Earth-size, planets may have readily formed at earlier epochs in the Universe’s history when metals were more scarce. We report Kepler spacecraft observations of Kepler-444, a metal-poor Sun-like star from the old population of the Galactic thick disk and the host to a compact system of five transiting planets with sizes between those of Mercury and Venus. We validate this system as a true five-planet system orbiting the target star and provide a detailed characterization of its planetary and orbital parameters based on an analysis of the transit photometry. Kepler-444 is the densest star with detected solar-like oscillations. We use asteroseismology to directly measure a precise age of 11.2+/-1.0 Gyr for the host star, indicating that Kepler-444 formed when the Universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. We thus show that Earth-size planets have formed throughout most of the Universe’s 13.8-billion-year history, leaving open the possibility for the existence of ancient life in the Galaxy. The age of Kepler-444 not only suggests that thick-disk stars were among the hosts to the first Galactic planets, but may also help to pinpoint the beginning of the era of planet formation.”

The star is believed to have 2 M dwarfs in orbit around it with the fainter companion 1.8 arc-seconds from the main star.

[https://en.wikipedia.org/wiki/Kepler-444]

WISE 1828+2650 is a brown dwarf or rogue planet of spectral class >Y2, located in constellation Lyra at approximately 47 light-years from Earth. It is the ‘archetypal member’ of the Y spectral class. It was discovered in 2011 from data collected by NASA’s 40 cm (16 in) Wide-field Infrared Survey Explorer (WISE) space telescope at infrared wavelength:

[https://en.wikipedia.org/wiki/WISE_1828%2B2650]

Reigning title-holder for coldest brown dwarf

NASA’s Wide-field Infrared Survey Explorer, or WISE, has uncovered the coldest brown dwarf known so far (green dot in very center of this infrared image). Called WISE 1828+2650, this chilly star-like body isn’t even as warm as a human body, at less than about 80 degrees Fahrenheit (25 degrees Celsius). Like other brown dwarfs, it began life like a star, collapsing under its own weight into a dense ball of gas. But, unlike a star, it didn’t have enough mass to fuse atoms at its core, and shine steadily with starlight. Instead, it has continued to cool and fade since its birth, and now gives off only a feeble amount of infrared light. WISE’s highly sensitive infrared detectors were able to catch the glow of this object during its all-sky scan, which lasted from Jan. 2010 to Feb. 2011.

WISE 1828+2650 is located in the constellation Lyra. The blue dots are a mix of stars and galaxies. This view shows three of WISE’s four infrared channels, color-coded blue, green and red, with blue showing the shortest infrared wavelengths and red, the longest.

[https://www.nasa.gov/mission_pages/WISE/multimedia/pia14721.html]

Messier 56 by Hubble Space Telescope

Messier 56 (also known as M56 or NGC 6779) is a globular cluster in the constellation Lyra. It was discovered by Charles Messier on January 19, 1779. The cluster is located almost midway along an imaginary line between Albireo (β Cygni) and Sulafat (γ Lyrae). It is a challenge to find with large (50–80 mm) binoculars, appearing as a slightly fuzzy star. The cluster can be resolved using a telescope with an aperture of 8 in (20 cm) or larger.

M56 is at a distance of about 32,900 light-years from Earth and measures roughly 84 light-years across, with a combined mass some 230,000 times that of the Sun. It is about 31–32 kly (9.5–9.8 kpc) from the Galactic Center and 4.8 kly (1.5 kpc) above the galactic plane. This cluster has an estimated age of 13.70 billion years and is following a retrograde orbit through the Milky Way. The properties of this cluster suggest that it may have been acquired during the merger of a dwarf galaxy, of which Omega Centauri forms the surviving nucleus. For Messier 56, the abundance of elements other than hydrogen and helium, what astronomers term the metallicity, has a very low value of [Fe/H] = –2.00 dex. This is equivalent to 1% of the abundance in the Sun.

The brightest stars in M56 are of 13th magnitude, while it contains only about a dozen known variable stars. In 2000, a diffuse X-ray emission was tentatively identified coming from the vicinity of the cluster. This is most likely interstellar medium that has been heated by the passage of the cluster through the galactic halo. The relative velocity of the cluster is about 177 km s−1, which is sufficient to heat the medium in its wake to a temperature of 940,000 K.

[https://en.wikipedia.org/wiki/Messier_56]

M57, also known as the ‘Ring Nebula’ or NGC 6720, is one of the best known planetary nebulae and the second to be discovered; its integrated magnitude is 8.8. It was discovered in 1779 by Antoine Darquier. Astronomers have determined that it is between 6,000 and 8,000 years old. The central star itself is a white dwarf with a temperature of 120,000 Kelvin. The nebula can be found halfway between Gamma Lyrae and Beta Lyrae:

M57: The Ring Nebula

Except for the rings of Saturn, the Ring Nebula (M57) is probably the most famous celestial band. Its classic appearance is understood to be due to our own perspective, though. The recent mapping of the expanding nebula’s 3-D structure, based in part on this clear Hubble image, indicates that the nebula is a relatively dense, donut-like ring wrapped around the middle of a football-shaped cloud of glowing gas. The view from planet Earth looks down the long axis of the football, face-on to the ring. Of course, in this well-studied example of a planetary nebula, the glowing material does not come from planets. Instead, the gaseous shroud represents outer layers expelled from the dying, once sun-like star, now a tiny pinprick of light seen at the nebula’s center. Intense ultraviolet light from the hot central star ionizes atoms in the gas. In the picture, the blue color in the center is ionized helium, the cyan color of the inner ring is the glow of hydrogen and oxygen, and the reddish color of the outer ring is from nitrogen and sulfur. The Ring Nebula is about one light-year across and 2,000 light-years away.

[http://apod.nasa.gov/apod/ap130605.html]

NGC 6745 is an irregular spiral galaxy in Lyra that is at a distance of 208 million light-years. Several million years ago, it collided with a smaller galaxy, which created a region filled with young, hot, blue stars. Astronomers do not know if the collision was simply a glancing blow or a prelude to a full-on merger, which would end with the two galaxies incorporated into one larger, probably elliptical galaxy:

A Galaxy Collision in NGC 6745

Galaxies don’t normally look like this. NGC 6745 actually shows the results of two galaxies that have been colliding for only hundreds of millions of years. Just off the above digitally sharpened photograph to the lower right is the smaller galaxy, moving away. The larger galaxy, pictured above, used to be a spiral galaxy but now is damaged and appears peculiar. Gravity has distorted the shapes of the galaxies. Although it is likely that no stars in the two galaxies directly collided, the gas, dust, and ambient magnetic fields do interact directly. In fact, a knot of gas pulled off the larger galaxy on the lower right has now begun to form stars. NGC 6745 spans about 80 thousand light-years across and is located about 200 million light-years away.
[http://apod.nasa.gov/apod/ap120930.html]

The April Lyrids are a meteor shower lasting from April 16 to April 26 each year. The radiant of the meteor shower is located in the constellation Lyra, near this constellation’s brightest star, Vega. Their peak is typically around April 22 each year. Counts typically range from 5 to 20 meteors per hour, averaging around 10.

The source of the meteor shower is particles of dust shed by the long-period Comet C/1861 G1 Thatcher. The April Lyrids are the strongest annual shower of meteors from debris of a long-period comet, mainly because as far as other intermediate long-period comets go (200–10,000 years), this one has a relatively short orbital period of about 415 years. The Lyrids have been observed for the past 2,600 years:

[https://en.wikipedia.org/wiki/Lyrids]

Lyrids in Southern Skies

Earth's annual Lyrid meteor shower peaked before dawn on April 22nd, as our fair planet plowed through dust from the tail of long-period comet Thatcher. Seen from the high, dark, and dry Atacama desert a waning crescent Moon and brilliant Venus join Lyrid meteor streaks in this composited view. Captured over 5 hours on the night of April 21/22, the meteors stream away from the shower’s radiant, a point not very far on the sky from Vega, alpha star of the constellation Lyra. The radiant effect is due to perspective as the parallel meteor tracks appear to converge in the distance. In the foreground are domes of the Las Campanas Observatory housing (left to right) the 2.5 meter du Pont Telescope and the 1.3 meter Optical Gravitational Lensing Experiment (OGLE) telescope.

[https://apod.nasa.gov/apod/ap170427.html]

[https://en.wikipedia.org/wiki/Lyra]

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