NGC 752

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Open star cluster
NGC 752
NGC 752.jpg
Amateur recording from NGC 752
AladinLite
Constellation Andromeda
Position
equinox : J2000.0
Right ascension 01 h 57 m 34.8 s
declination + 37 ° 50 ′ 00 ″
Appearance

classification III 1 m
Brightness  (visual) 5.7 likes
Angular expansion 75 '
Number of stars approx. 60
Brightest star +8.96 mag
Variable stars DS Andromedae
Redness ( excess color  E (BV)) 0.034 mag
Physical data

Affiliation Milky Way
Redshift (12 ± 6)  ·  10 −6
Radial velocity (3.5 ± 1.8) km / s
distance  1500 ly
(457 pc )
Absolute brightness −2.3 mag
diameter 19 ly
Age about 1.1 billion years
Metallicity [Fe / H] −0.08
history
Discovered by Giovanni Battista Hodierna
Discovery time before 1654
Catalog names
 NGC  752 • C 0154 + 374 • OCl 363 •  Mel  12 •  Cr  23 • Lund 64 •  GC  457 •  H  VII 32 •  h  174 •

NGC 752 is a +5.7 mag bright open star cluster with an area of ​​about 75 'in the constellation Andromeda . It is around 1,500 light years away from the solar system and has a diameter of around 30 light years. According to the state of development of the star cluster, its age is estimated to be 1.1 to 1.6 billion years. Due to his old age he is relatively poor in stars and already very scattered. NGC 752 can be seen as a faint nebula with the naked eye.

The discovery of NGC 752 goes back to the Sicilian scholar and priest, Giovanni Battista Hodierna , who discovered this cluster shortly before 1654. Hodierna observed under a dark country sky with a Galilean telescope that was only 20 times magnified. Later, however, his work was hardly noticed, and it was not until the 1980s that his work was rediscovered.

Individual evidence

  1. ↑ NASA / IPAC EXTRAGALACTIC DATABASE
  2. ↑ a b SEDS : NGC 759
  3. ↑ SIMBAD Query
  4. ↑ WEBDA
  5. ↑ Stars and Space October 2013 p. 66f
  6. ↑ Seligman
  7. ↑ Stars and Space November 2007 p. 62