NASA Hubble Space Telescope's new Advanced Camera for Surveys (ACS) has provided the clearest visible-light view yet of the nearby quasar 3C 273. The ACS' coronagraph was used to block the light from the brilliant central quasar, revealing that the quasar's host galaxy is significantly more complex than had been suggested in previous observations. Features in the surrounding galaxy normally drowned out by the quasar's glow now show up clearly. The ACS reveals a spiral plume wound around the quasar, a red dust lane, and a blue arc and clump in the path of the jet blasted from the quasar. These details had never been seen before. Previously known clumps of hot gas and the inner blue optical jet are now resolved more clearly.
The power of the ACS coronagraph is demonstrated in this picture. The Hubble image on the left, taken with the Wide Field Planetary Camera 2, shows the brilliant quasar but little else. The diffraction spikes demonstrate the quasar is truly a point-source of light (like a star) because the black hole's "central engine" is so compact. Once the blinding "headlight beam" of the quasar is blocked by the ACS (right), the host galaxy pops into view. Note that the ACS' occulting "finger" and other coronagraphic spot are seen in black near the top of the ACS High Resolution Channel image.
Quasars (also known as QSOs - short for quasi-stellar objects) were discovered in the early 1960s, but at least two decades passed before astronomers had observational evidence that they reside in galaxies. They now are commonly accepted to be supermassive black holes accreting infalling gas and dust. Using the ACS, astronomers want to learn what activities in a quasar's host galaxy feed the black hole, allowing it to "turn on" as a quasar.
Credits
WFPC2 image: NASA and J. Bahcall (IAS);ACS image: NASA, A. Martel (JHU), H. Ford (JHU), M. Clampin (STScI), G. Hartig (STScI), G. Illingworth (UCO/Lick Observatory), the ACS Science Team and ESA
| About The Object | |
|---|---|
| Object Name | 3C 273 |
| Object Description | Quasar |
| R.A. Position | 12h 29m 6.7s |
| Dec. Position | 02° 3' 9.0" |
| Constellation | Virgo |
| Distance | 1.9 billion light-years (580 megaparsecs) |
| Dimensions | The ACS image is roughly 30 arcseconds (275 kly or 85 kiloparsecs) in width. |
| About The Data | |
| Data Description | Principal Astronomers, WFPC2 data: J. Bahcall (IAS) ACS science team: H.C. Ford (JHU), G.D. Illingworth (UCO/Lick Observatory), N. Benitez (JHU), M. Clampin (STScI), G.F. Hartig (STScI), D.R. Ardila (JHU), F. Bartko (Bartko Science & Technology), J.P. Blakeslee (JHU), R.J. Bouwens (UCO/Lick Obs.), T.J. Broadhurst (Racah Institute of Physics, The Hebrew University), R.A. Brown (STScI), C.J. Burrows (STScI), E.S. Cheng (NASA-GSFC), N.J.G. Cross (JHU), P.D. Feldman (JHU), M. Franx (Leiden Observatory), D.A.Golimowski (JHU), C. Gronwall (PSU), L. Infante (Pontificia Universidad Catolica de Chile), R.A. Kimble (NASA GSFC), J.E. Krist (STScI), M.P. Lesser (Steward Obs.), A.R. Martel (JHU), F. Menanteau (JHU), G.R. Meurer (JHU), G.K. Miley (Leiden Obs.), M. Postman (STScI), P. Rosati (ESO), M. Sirianni (JHU), W.B. Sparks (STScI), H.D. Tran (JHU), Z.I. Tsvetanov (JHU), R.L. White (STScI/JHU), and W. Zheng (JHU) |
| Instrument | HST>WFPC2 (left), HST>ACS/HRC (right) |
| Exposure Dates | June 4, 1994 (left), and July 19-20, 2002 (right) |
| Filters | WFPC2: F606W (V) ACS/HRC: F475W (g), F502N ([O III]), F606W (V), F814W (I) |
| About The Image | |
| Compass Image |  |
| About The Object | |
|---|---|
| Object Name | A name or catalog number that astronomers use to identify an astronomical object. |
| Object Description | The type of astronomical object. |
| R.A. Position | Right ascension – analogous to longitude – is one component of an object's position. |
| Dec. Position | Declination – analogous to latitude – is one component of an object's position. |
| Constellation | One of 88 recognized regions of the celestial sphere in which the object appears. |
| Distance | The physical distance from Earth to the astronomical object. Distances within our solar system are usually measured in Astronomical Units (AU). Distances between stars are usually measured in light-years. Interstellar distances can also be measured in parsecs. |
| Dimensions | The physical size of the object or the apparent angle it subtends on the sky. |
| About The Data | |
| Data Description |
|
| Instrument | The science instrument used to produce the data. |
| Exposure Dates | The date(s) that the telescope made its observations and the total exposure time. |
| Filters | The camera filters that were used in the science observations. |
| About The Image | |
| Image Credit | The primary individuals and institutions responsible for the content. |
| Publication Date | The date and time the release content became public. |
| Color Info | A brief description of the methods used to convert telescope data into the color image being presented. |
| Orientation | The rotation of the image on the sky with respect to the north pole of the celestial sphere. |
