The Local Volume HI Survey (LVHIS)

NGC 300

NGC 300 (HIPASS J0054-37) is large, late-type spiral galaxy in the Sculptor Group, located ~8 degrees (300 kpc) from NGC 55. Both galaxies and their large-scale surroundings were recently mosaicked in HI with the ATCA by Westmeier et al. (2011, 2013) who used 32 pointings covering an area of about 2 degr × 2 degr to reveal much larger gas envelopes than previously known. They also found disturbed outer disc gas in both galaxies as well as high-velocity clouds (HVCs) surrounding NGC 55. We refer to Westmeier et al. for a detailed analysis and literature overview of both Sculptor galaxies.

The large galaxies NGC 55 and NGC 300, together with the dwarf galaxies ESO 294-G010, ESO 410-G005, UGCA 438 and IC 5152 (all detected in HI) form a small subgroup at the near side of the Sculptor Group at a distance of ~2 Mpc.

The ATCA HI distribution of NGC 300 is huge, extending well beyond previous measurements. The outer HI disc is strongly warped, exhibiting a significant twist of the position angle from east-west to nearly north-south. The wide-field HI mapping with a compact array was crucial to discover the extent of the outer disc, which contains nearly 50% of the HI mass. Westmeier et al. (2011) carry out a detailed analysis of the gas kinematics and dark matter distribution, finding a slightly decreasing rotation curve (vmax ~ 100 km/s) that extends to a radius of ~20 kpc. Significant asymmetries in NGC 300's outer disc hint at the possibility of ram-pressure stripping of gas by the intragroup medium. We measure FHI = 1758.3 Jy km/s, about 10% lower than Parkes HI measurements (Koribalski et al. 2004, Westmeier et al. 2017).

Reference: Koribalski et al. 2018 * LVHIS database * LVHIS homepage * next

Last updated on 18 Feb 2018. © Copyright CSIRO