| UGC 6945 | |
|---|---|
 UGC 6945 by Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Ursa Major |
| Right ascension | 11h 57m 54.87s[1] |
| Declination | +36° 23′ 32.8″[1] |
| Redshift | 0.035388 ± 0.000130[2] |
| Heliocentric radial velocity | +10,511 km s−1[2] |
| Distance | 175 Mpc (570 Mly) |
| Characteristics | |
| Type | S?[3] |
| Apparent size (V) | 1.202′[4] |
| Other designations | |
| Arp 194, VV 126 | |
UGC 6945 (also known as Arp 194) is a trio of interacting galaxies. The highly disrupted galaxy to the northwest is actually two galaxies in the advanced stages of merger, and has an angular size of 0′.8 × 0′.6. About 40″ to the southeast is a third galaxy with an angular size of 0′.35 × 0′.35.
Based upon a radial velocity of about 10,500 km s−1, the interacting pair of galaxies at the northwest are located at a distance of 175 Mpc (570 Mly) from us (assuming a Hubble constant value of 60 km s−1 Mpc−1). If we further assume that the third galaxy lies at the same distance away from us, we find that the galaxies are separated by a projected linear distance of roughly 34 Kpc (110 Kly),[5] though later findings from Hubble may cast this assumption into doubt (see below).
As the pair of galaxies in the north gravitationally interact with each other, tidally-stripped gas from both galaxies is draped over the southern galaxy as a series of blobs, which are fueling a burst of star formation.[5] While it has long been believed to be interacting with the northern galaxy, images from the Hubble Space Telescope clearly show that this stream of material is actually superimposed on the southern galaxy.[6] This suggests that this third galaxy may actually lie in the background. Due to this uncertainty, the third galaxy may not be involved in the interaction.
- ^ a b Cite error: The named reference
apjss125_2_409was invoked but never defined (see the help page). - ^ a b Cite error: The named reference
apjs99_391was invoked but never defined (see the help page). - ^ "Results for object NGC UGC 6945 (UGC 6945)". NASA/IPAC Extragalactic Database. California Institute of Technology. Retrieved 2021-02-28.
- ^ Cite error: The named reference
SIMBADwas invoked but never defined (see the help page). - ^ a b Cite error: The named reference
aj125_4_1897was invoked but never defined (see the help page). - ^ "Hubble Celebrates Its 19th Anniversary with a". HubbleSite.org. Retrieved 2020-02-17.