Star Clusters in the Andromeda Galaxy

 Star Clusters in the Andromeda Galaxy

[Top] – This is a Hubble Space Telescope mosaic of 414 photographs of the nearest major galaxy to our Milky Way galaxy, the Andromeda galaxy (M31). The vast panorama was assembled from nearly 8,000 separate exposures taken in near-ultraviolet, visible, and near-infrared light. Embedded within this view are 2,753 star clusters. The view is 61,600 light-years across and contains images of 117 million stars in the galaxy's disk.

[Bottom-Left] – An enlargement of the boxed field in the top image reveals myriad stars and numerous open star clusters as bright blue knots. Hubble's bird's-eye view of M31 allowed astronomers to conduct a larger-than-ever sampling of star clusters that are all at the same distance from Earth, 2.5 million light-years. The view is 4,400 light-years across.

[Bottom-Right] – This is a view of six bright blue clusters extracted from the field. Hubble astronomers discovered that, for whatever reason, nature apparently cooks up stars with a consistent distribution from massive stars to small stars (blue supergiants to red dwarfs). This remains a constant across the galaxy, despite the fact that the clusters vary in mass by a factor of 10 and range in age from 4 million to 24 million years old. Each cluster square is 150 light-years across.

Credits

NASA, ESA, J. Dalcanton, B.F. Williams, and L.C. Johnson (University of Washington), the PHAT team, and R. Gendler

About The Object
Object Name M31, Andromeda Galaxy
Object Description Spiral Galaxy
R.A. Position 00h 42m
Dec. Position +41° 15'
Constellation Andromeda
Distance 2.5 million light-years (0.8 megaparsecs)
About The Data
Data Description Data of M31 were obtained from the HST PHAT Treasury Proposals: P.I. J. Dalcanton (University of Washington) et al. , , , , , , , , , , , , , , , , , , , , , , and . The science team comprises: D. Weisz and L.C. Johnson (University of Washington), D. Foreman-Mackey (New York University), A. Dolphin (Raytheon Company), L. Beerman, B. Williams, and J. Dalcanton (University of Washington), H.-W. Rix (Max Planck Institute for Astronomy, Heidelberg), D. Hogg (New York University/Max Planck Institute for Astronomy, Heidelberg), M. Fouesneau (Max Planck Institute for Astronomy, Heidelberg), B. Johnson (Harvard-Smithsonian Center for Astrophysics), E. Bell (University of Michigan), M. Boyer (STScI), D. Gouliermis (Max Planck Institute for Astronomy/University of Heidelberg), P. Guhathakurta (University of California, Santa Cruz), J. Kalirai (STScI), A. Lewis (University of Washington), A. Seth (University of Utah), and E. Skillman (University of Minnesota).
Instrument HST>ACS/WFC, HST>WFC3/UVIS, and HST>WFC3/IR
Exposure Dates July 2010 - October 2013
Filters Bottom images: F336W (U), F475W (g), F814W (I), and F160W (H); Top Image: F475W (g) and F814W (I)
About The Image
Color Info These images are composites of separate exposures acquired by the ACS and WFC3 instruments on the Hubble Space Telescope. Several filters were used to sample broad wavelength ranges. 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: WFC3/UVIS F336W (U) Green: ACS/WFC F475W (g) Yellow: ACS/WFC F814W (I) Red: WFC3/IR F160W (H)
Compass Image Star Clusters in the Andromeda Galaxy
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.