Arp 7

Arp 7
Arp 7
	Arp 7 by PanSTARRS
Observation data (J2000 epoch)
Constellation	Hydra
Right ascension	8h 50m 30.0s
Declination	−16° 37′ 00″
Redshift	0.018620±0.000002
Heliocentric radial velocity	5,582±1 km/s
Galactocentric velocity	5,384±8 km/s
Distance	103.9 ± 146.4 Mly (31.853 ± 44.901 Mpc)
Apparent magnitude (V)	14.5
Characteristics
Type	SB(rs)bc: HII
Size	40,737 ly; (12.49 kpc); (diameter; 25.0 B-mag arcsec−2); 28,767 ly × 26,451 ly; (8.82 kpc × 8.11 kpc); (diameter; "total" magnitude)
Apparent size (V)	1.3′ × 1.0′
Other designations
	PGC 024836, APG 7

Arp 7 (PGC 24836) is a spiral galaxy in the constellation Hydra.^[1] Redshift-independent measurements of its distance vary widely, from 5.9 to 83.7 megaparsecs (19.24 to 273.0 million light-years).^[3] Its morphological classification is SB(rs)bc,^[3] meaning it is a barred spiral galaxy with some ring-like structure.

Arp 7 was imaged by Halton Arp and included in his Atlas of Peculiar Galaxies under the category of 'split arm' galaxies.^[5] Five other galaxies are also included in this section of the atlas: Arp 8 (NGC 497), Arp 9 (NGC 2523), Arp 10 (UGC 1775), Arp 11 (UGC 717), and Arp 12 (NGC 2608).

References

1 2 Seligman, Courtney. "Celestial Atlas: PCG Objects 24500–4999". Retrieved 2015-11-25.
1 2 3 Results for ARP 007. SIMBAD Astronomical Database. Retrieved 2015-11-25.
1 2 3 4 5 6 7 8 9 10 11 12 "Detailed Information for Object Arp 7". NASA/IPAC Extragalactic Database. Retrieved August 3, 2025.
↑ . Bibcode:1991RC3.9.C...0000d. {{cite journal}}: Cite journal requires |journal= (help); Missing or empty |title= (help)
↑ Arp, Halton (1966). "Atlas of Peculiar Galaxies". Figure 1. Retrieved 2015-11-25.

Notes

1 2 The quick-look major axis physical diameters given by NED of 12.49 kiloparsecs (40,700 light-years) and 8.82 by 8.11 kiloparsecs (28,800 by 26,500 light-years) were based on distance estimates of 31.853 ± 44.901 Mpc (103.9×10^⁶ ± 146.4×10^⁶ ly) using a scale of 154.4 parsec/arcsec multiplied with given angular diameters.

External links

[cseligman-1] 1 2 Seligman, Courtney. "Celestial Atlas: PCG Objects 24500–4999". Retrieved 2015-11-25.

[simbad-2] 1 2 3 Results for ARP 007. SIMBAD Astronomical Database. Retrieved 2015-11-25.

[ned-3] 1 2 3 4 5 6 7 8 9 10 11 12 "Detailed Information for Object Arp 7". NASA/IPAC Extragalactic Database. Retrieved August 3, 2025.

[vaucouleurs-4] . Bibcode:1991RC3.9.C...0000d. {{cite journal}}: Cite journal requires |journal= (help); Missing or empty |title= (help)

[6] Arp, Halton (1966). "Atlas of Peculiar Galaxies". Figure 1. Retrieved 2015-11-25.

[Size_correction-5] 1 2 The quick-look major axis physical diameters given by NED of 12.49 kiloparsecs (40,700 light-years) and 8.82 by 8.11 kiloparsecs (28,800 by 26,500 light-years) were based on distance estimates of 31.853 ± 44.901 Mpc (103.9×10^⁶ ± 146.4×10^⁶ ly) using a scale of 154.4 parsec/arcsec multiplied with given angular diameters.

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v t e Astronomical catalogs
PGC	PGC 24832 PGC 24833 PGC 24834 PGC 24835 PGC 24836 PGC 24837 PGC 24838 PGC 24839 PGC 24840
Arp	Arp 1 Arp 2 Arp 3 Arp 4 Arp 5 Arp 6 Arp 7 Arp 8 Arp 9 Arp 10 Arp 11 Arp 12 Arp 13

This page was redesigned at the edge.

References

Notes

External links