| Teacup galaxy | |
|---|---|
The Teacup Galaxy as seen by the Hubble Space Telescope
Credit: NASA, ESA, W. Keel (University of Alabama), and the Galaxy Zoo Team | |
| Observation data (J2000.0 epoch) | |
| Constellation | Boötes[1] |
| Right ascension | 14h30m 29.868s[2] |
| Declination | +13° 39′ 11.79″[2] |
| Redshift | 0.08513[2] |
| Distance | 1,100 Mly (337.26 Mpc) |
| Characteristics | |
| Apparent size (V) | 0.223' × 0.197'[2] |
| Other designations | |
| FIRST J143029.9+133912, IRAS F14281+1352, LEDA 1436754, NVSS J143030+133912, SDSS J1430+1339 | |
The Teacup galaxy,[3] also known as the Teacup AGN[2]orSDSS J1430+1339 is a low redshift type 2 quasar,[4] showing an extended loop of ionized gas resembling a handle of a teacup, which was discovered by volunteers of the Galaxy Zoo project and labeled as a Voorwerpje.[5]
The Teacup galaxy is dominated by a bulge and has an asymmetric structure with a shell-like structure and a tidal tail. The shell and tail are signatures of a recent merger of two galaxies.[6] Dust lanes in the system are interpreted as a gas-rich merger.[7] Several candidate star clusters were identified in this galaxy with Hubble Space Telescope images.[6] Observations with the Gran Telescopio Canarias showed that the Teacup Galaxy has a giant reservoir of ionized gas extending up to 111 kpc. The optical/radio bubbles seem to be expanding across this intergalactic medium.[4]
Early studies of the Teacup AGN suggested that it is fading,[8] although there was no clear evidence.[9] Observations with VLT/SINFONI showed a blueshifted nuclear outflow with a velocity of 1600–1800 km/s.[10] Observations in x-rays with Swift, XMM-Newton and Chandra revealed a powerful, highly obscured active galactic nucleus. This new result suggests that the AGN might not require fading. The quasar has dimmed by only a factor of 25 or less over the past 100,000 years.[11][1]
One bubble was discovered by Galaxy Zoo volunteers in SDSS images as a 5 kpc loop of ionized gas.[5] The loop is dominated by emission lines, such as hydrogen alpha and doubly ionized oxygen, which gives the loop seen in SDSS images a purple color. The emission of [O II] is extremely strong in the Teacup AGN and the quasar 3C 48 shows a similar [O II]/Hβ ratio.[8]
Follow-up observations with the Very Large Array showed two 10-12 kpc bubbles, one "eastern bubble", consistent with the loop in optical observations and a "western bubble", only visible in radio wavelengths. The study also found a bright emission towards the north-east of the AGN, which is consistent with high-velocity ionized gas (-740 km/s). The bubbles are either created by small-scale radio jets or by quasar winds.[7]
Observations with Chandra revealed a loop in x-ray emission, consistent with the "eastern bubble". The Chandra data also show evidence for hotter gas within the bubble, which may imply that a wind of material is blowing away from the black hole. Such a wind, which was driven by radiation from the quasar, may have created the bubbles found in the Teacup.[11][1]
