Monster Galaxy Lacks a Bright Core

 Monster Galaxy Lacks a Bright Core

The giant elliptical galaxy in the center of this image, taken by NASA's Hubble Space Telescope, is the most massive and brightest member of the galaxy cluster Abell 2261.

Spanning a little more than one million light-years, the galaxy is about 10 times the diameter of our Milky Way galaxy. The bloated galaxy is a member of an unusual class of galaxies with a diffuse core filled with a fog of starlight. Normally, astronomers would expect to see a concentrated peak of light around a central black hole. The Hubble observations revealed that the galaxy's puffy core, measuring about 10,000 light-years, is the largest yet seen.

The observations present a mystery, and studies of this galaxy may provide insight into how black hole behavior may shape the cores of galaxies.

Astronomers used Hubble's Advanced Camera for Surveys and Wide Field Camera 3 to measure the amount of starlight across the galaxy, dubbed A2261-BCG. Abell 2261 is located three billion light-years away.

The observations were taken March to May 2011. The Abell 2261 cluster is part of a multi-wavelength survey called the Cluster Lensing And Supernova survey with Hubble (CLASH).

Credits

Credit: NASA, ESA, M. Postman (STScI), T. Lauer (NOAO), and the CLASH team

About The Object
Object Name Abell 2261, A2261-BCG
Object Description Elliptical Galaxy
R.A. Position 17h 22m 28.34s
Dec. Position 32° 9' 12.66"
Constellation Hercules
Distance 3 billion light-years (920 megaparsecs)
About The Data
Data Description The image was created from Hubble data from proposal : M. Postman (STScI) et al.
Instrument HST>ACS/WFC, and HST>WFC3/IR
Exposure Dates March - May 2011, Exposure Time: 13 hours
Filters ACS/WFC: F435W (B), F475W (g), F606W (V) + F625W (r) + F775W (i), F814W (I), and F850LP (z); WFC3/IR: F105W (Y), F110W (YJ), F125W (J), F140W (JH), and F160W (H)
About The Image
Color Info This image is a composite of separate exposures acquired by the ACS instrument. Several filters were used to sample various wavelengths. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are: Blue: ACS/WFC F435W (B) + F475W (g) Green: ACS/WFC F606W (V) + F625W (r) + F775W (i) Red: ACS/WFC F814W (I) + F850LP (z), WFC3/IR F105W (Y) + F110W (YJ) + F125W (J) + F140W (JH) + F160W (H)
Compass Image Monster Galaxy Lacks a Bright Core
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
  • Proposal: A description of the observations, their scientific justification, and the links to the data available in the science archive.
  • Science Team: The astronomers who planned the observations and analyzed the data. "PI" refers to the Principal Investigator.
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.