"X" Structure at Core of Whirlpool Galaxy (Four-frame Comparison)

 "X" Structure at Core of Whirlpool Galaxy (Four-frame Comparison)

Hubble Space Telescope provides a detailed look at the core of the giant spiral galaxy M51. These images, taken at different wavelengths of light, reveal complex structure and detail in the galaxy's core, which is thought to hide a massive black hole.

[upper left] – A ground telescopic image of M51, the Whirlpool Galaxy, taken with Kitt Peak National Observatory's 4-meter telescope. M51 is spectacular because it is one of the nearest and brightest galaxies and is tilted nearly face-on to Earth, allowing an unobstructed view of the bright nucleus. The image is 14,000 light-years across.

[upper right] – A NASA Hubble Space Telescope image of the center of M51, taken in visible light with the Wide Field Planetary camera (in PC mode). This image provides the first direct view of what may be an immense ring of dust which fuels a massive black hole at the heart of M51. This "donut-ring" or torus appears as the darkest bar in the striking "X" silhouetted across the bright nucleus. The 'X" marks the exact position of the black hole. Because the giant ring is tilted edge-on as viewed from Earth, it hides the black hole from direct view. The second bar of the "X" could be second disk seen edge on, or possibly rotating gas and dust in M51 interacting with the jets and ionization cones. The image is 1100 light-years across.

[bottom right] – An HST image of the same region, filtered in the light of ionized oxygen shows an hour-glass or double ionization cone structure bisected by the widest bar of the X. The black hole's hot accretion disk, buried deep inside the torus, is presumably the source of the ionizing radiation. The dusty ring confines the radiation from the accretion disk so that it can only escape through the "donut hole' of the torus as a pair of oppositely-directed cones of light.

[bottom left] – An HST image of the same region, filtered in the light of ionized hydrogen, shows a double-lobed hour-glass structure across the nucleus. The dust ring determines the axis of a jet of material being accelerated away from the black hole. The high-speed jet lies in the galaxy's plane and plows into the interstellar medium. The interaction of the nuclear jet with the interstellar medium is analogous to a fire hose directed against a large pile of sand. The jet inflates a cavity of ionized gas which expands and advances into the gas and dust in the M51's disk.

Credits

H. Ford (JHU/STScI), the Faint Object Spectrograph IDT, and NASA

About The Object
Object Name M51, Whirlpool Galaxy
R.A. Position 13h 29m 52.36s
Dec. Position 47° 11' 40.8"
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
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.