Comet Galaxy

Comet Galaxy
The Comet Galaxy, as taken by the Hubble Space Telescope
Observation data (J2000 epoch)
ConstellationSculptor
Right ascension23h 51m 44.03s
Declination−26° 03′ 59.6″
Redshift0.2265
Heliocentric radial velocity67,753±89 km/s
Galactocentric velocity67,778±89 km/s
Distance3,250 ± 227.7 Mly (996.6 ± 69.8 Mpc)h−1
0.6774
(Comoving)
2.777 Gly (0.8514 Gpc)h−1
0.6774
(Light-travel)
Group or clusterAbell 2667
Apparent magnitude (B)18.642
Characteristics
TypedIrr
Mass3.8×108 (stellar) M☉
Size170,000 ly × 142,000 ly
(52.2 kpc × 43.5 kpc)
Apparent size (V)0.18′ × 0.15′
Notable featuresStripped stream of bright blue knots and diffuse wisps of young stars
Other designations
2dFGRS TGS132Z144, EQ J235144-260358, WISEA J235144.05-260357.9, LEDA 3234374,

The Comet Galaxy (EQ J235144-260358) is a peculiar spiral galaxy located 996.6 megaparsecs (3.3 billion light-years) from Earth in the galaxy cluster Abell 2667 and the constellation Sculptor. This galaxy has slightly more stellar mass than the Milky Way. It was detected on 2 March 2007 with the Hubble Space Telescope.

The galaxy is currently traveling through the galactic cluster at 3.6 million km/h (2.17 million mi/h), and as a result is being stripped of much of its matter as a result of the cluster's tidal forces.

Structure

The Comet Galaxy is a unique, peculiar galaxy that features an extended stream of interstellar gas, blue knots (or large clumps of matter), and wisps of bright-blue young stars. It is currently traveling through Abell 2667 at 3.6 million km/h (1,000 km/s), and as a result of the gravitational forces of the cluster, much of the galaxy's matter is being stripped out into a long tail, similar to a comet; as a result, one of the galaxy's arms appears flatter then the surrounding arms, while the tail contains numerous bright starburst regions.

Its isophotal diameter is currently unknown. Based off its apparent size of 10.8 arcseconds for the main galaxy, along with the galaxy's distance from Earth, it approximately corresponds to a diameter of 52.2 kiloparsecs (170,000 light-years), thus making it slightly larger than the Andromeda Galaxy.

Fate

The Сomet Galaxy is currently being ripped apart as a result of traveling through a large galaxy cluster at speeds of greater than 2 million mph. As the galaxy speeds through, its gas and stars are being stripped away by the tidal forces and charged particles exerted by the cluster. Also contributing to this destructive process is the pressure of the cluster's hot intergalactic gas and plasma, reaching temperatures as high as 100 million degrees. Scientists estimate that the total duration of the transformation process is close to one billion years; the galaxy is seen to be roughly 400 million years into this process.

In spite of the galaxy's large mass, the spiral will inevitably lose majority of its gas and dust, resulting in a gas-poor lenticular or elliptical galaxy with an older population of red stars. The finding sheds light on the process by which some gas-rich galaxies might evolve into gas-poor galaxies over billions of years. Observations also reveal one mechanism that may result in intergalactic stars.

See also

Notes

  1. 1 2 Calculated based on minor and major angular diameters and the quoted comoving distance:

References

  1. 1 2 3 4 Cortese, L. (2007). "The strong transformation of spiral galaxies infalling into massive clusters atz≈ 0.2". Monthly Notices of the Royal Astronomical Society. 376 (1): 157–172. arXiv:astro-ph/0703012. Bibcode:2007MNRAS.376..157C. doi:10.1111/j.1365-2966.2006.11369.x. S2CID 17152868.
  2. 1 2 3 4 5 6 7 "2dFGRS TGS132Z144". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-12-20.
  3. 1 2 3 4 5 6 7 8 9 10 11 12 13 WISEA J235144.05-260357.9 on NASA/IPAC Extragalactic Database
  4. ↑ Colless, Matthew; Dalton, Gavin; Maddox, Steve; Sutherland, Will; Norberg, Peder; Cole, Shaun; Bland-Hawthorn, Joss; Bridges, Terry; Cannon, Russell; Collins, Chris; Couch, Warrick; Cross, Nicholas; Deeley, Kathryn; De Propris, Roberto; Driver, Simon P.; Efstathiou, George; Ellis, Richard S.; Frenk, Carlos S.; Glazebrook, Karl; Jackson, Carole; Lahav, Ofer; Lewis, Ian; Lumsden, Stuart; Madgwick, Darren; Peacock, John A.; Peterson, Bruce A.; Price, Ian; Seaborne, Mark; Taylor, Keith (2001). "The 2dF Galaxy Redshift Survey: Spectra and redshifts". Monthly Notices of the Royal Astronomical Society. 328 (4): 1039. arXiv:astro-ph/0106498. Bibcode:2001MNRAS.328.1039C. doi:10.1046/j.1365-8711.2001.04902.x.
  5. 1 2 3 4 5 6 7 8 9 Fumagalli, Mattia; Gavazzi, G.; Scaramella, R.; Franzetti, P. (April 2011), "Constraining the ages of the fireballs in the wake of the dIrr galaxy VCC 1217/IC 3418", Astronomy & Astrophysics, 528: 9, arXiv:1011.1665, Bibcode:2011A&A...528A..46F, doi:10.1051/0004-6361/201015463, S2CID 119240960, A46
  6. 1 2 3 4 5 "Hubble sees "Comet Galaxy" being ripped apart by galaxy cluster". ESA/Hubble. L. Cortese. 2 March 2007.