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NGC 495

Coordinates: Sky map 01h 22m 56.0s, +33° 28′ 18″
From Wikipedia, the free encyclopedia
NGC 495
NGC 495
SDSS view of NGC 495
Observation data (J2000[1] epoch)
ConstellationPisces[2]
Right ascension01h 22m 56.0s[3]
Declination+33° 28′ 18″[3]
Redshift+0.013679 ± 0.000073[1]
Heliocentric radial velocity(4073 ± 22) km/s[1]
Distance184 Mly[4]
Apparent magnitude (V)13.0[2]
Characteristics
TypeSB0-a[2]
Apparent size (V)1.2' × 0.8'[2]
Other designations
PGC 5037, UGC 920, GC 278, MCG 5-4-35, 2MASS J01225595+3328171, H 3.156,[2][1][5]

NGC 495, also occasionally referred to as PGC 5037, UGC 920 or GC 278, is a barred spiral galaxy in the constellation Pisces.[2] It is located approximately 184 million light-years from the Solar System[4] and was discovered on 12 September 1784 by astronomer William Herschel.[5]

Observation history

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The object was discovered by Herschel along with NGC 496 and NGC 499. He initially described the discovery as "Three [NGC 495 along with NGC 496 and 499], eS and F, forming a triangle.". As he observed the trio again the next night, he was able to make out more detail: "Three, forming a [right triangle]; the [right angle] to the south NGC 499, the short leg preceding [NGC 495], the long towards the north [NGC 496]. Those in the legs [NGC 495 and 496] the faintest imaginable; that at the rectangle [NGC 499] a deal larger and brighter, but still very faint."[6]

NGC 495 was later also observed by Heinrich d'Arrest and Herman Schultz[5] who first noted the object's accurate position. This position is also noted in the New General Catalogue.[6]

One supernova has been observed in NGC 495: SN 1999ej (type Ia, mag. 18.1).[7]

Description

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John Dreyer, creator of the New General Catalogue, uses Herschel's initial notation to describe the position of NGC 495 ("very faint, small, 1st of 3").[5]

Modern observations however call NGC 495 a bright central galaxy with an apparent size of about 1.2' by 0.8'. It also includes fainter outer extensions, about 2.6' by 1.5'.[5] The galaxy is also classified as a barred spiral galaxy of Hubble type SB0-a.[2]

See also

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References

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  1. ^ a b c d "NGC 495". Retrieved 2017-11-07.
  2. ^ a b c d e f g "Revised NGC Data for NGC 495". spider.seds.org. Retrieved 2017-10-05.
  3. ^ a b "Your NED Search Results". ned.ipac.caltech.edu. Retrieved 2017-11-07.
  4. ^ a b An object's distance from Earth can be determined using Hubble's law: v=Ho is Hubble's constant (70±5 (km/s)/Mpc). The relative uncertainty Δd/d divided by the distance is equal to the sum of the relative uncertainties of the velocity and v=Ho
  5. ^ a b c d e "New General Catalog Objects: NGC 450 - 499". cseligman.com. Retrieved 2017-11-07.
  6. ^ a b "astronomy-mall.com/Adventures.In.Deep.Space/NGC%201-7840%20complete.htm". Astronomy Mall. Retrieved 2017-11-07.
  7. ^ Transient Name Server entry for SN 1999ej. Retrieved 31 March 2023.
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