Merging galaxy NGC 7252 From the Ground (left) and From Hubble (right)

 Merging galaxy NGC 7252 From the Ground (left) and From Hubble (right)

[Left] Ground-based Telescopic Photograph NGC 7252 has been considered the prototypical example of a merger between two disk-shaped galaxies. The galaxy has a pair of long tails that are unambiguous evidence of the effects of gravitational tidal forces from a galaxy merger. The galaxy is nicknamed the "Atoms-for-Peace" galaxy because its stars form a bizarre loop-like structure that resembles a schematic diagram of electrons orbiting an atomic nucleus. (In December 1953, U.S. President Dwight 0. Eisenhower made his "Atoms for Peace" speech to foster peaceful applications of nuclear energy.) The galaxy is located 300 million light-years away in the constellation Aquarius.

[Right] Hubble Space Telescope Planetary Camera Image of Galaxy Core A NASA Hubble Space Telescope image of the core of the peculiar galaxy NGC 7252 reveals a striking "mini-spiral" disk of gas and stars, and about 40 exceptionally bright and young globular star clusters.

The visible light image was taken with the Wide Field and Planetary Camera (WFPC) in PC mode, on October 10, 1992. The image has been subject to computer image reconstruction. The strong spiral structure is 10,000 light-years across (3.5 arc seconds); the entire picture is 46,000 light-years across. Hubble's resolution is so good the astronomers can measure the diameters of the clusters (0.04 arc seconds, the apparent size of a dime at a distance of 60 miles). They turn out to be about 60 light-years in diameter, the same size as globular clusters that orbit our Milky Way galaxy.

The pinwheel-shaped disk of gas and young stars has an uncanny resemblance to a face-on spiral galaxy. Yet the disk is only 1/20 the diameter of the total galaxy. The disk was probably fueled by the collision.

Credits

Left image: Dr. Francois Schweizer, taken with 4-meter telescope at the Cerro Tololo Inter-American Observatory.;
Right Image: B. Whitmore (STScI), and NASA;
Co-investigators: Francois Schweizer of the Carnegie Institution of Washington, Washington, D.C., and Claus Leitherer, Kirk Borne, and Carmelle Robert of STScI.

About The Object
Object Name NGC 7252
R.A. Position 22h 20m 44.77s
Dec. Position -24° 40' 41.8"
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
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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.