Legacy Astronomical Images > Galaxies Series > Spiral Galaxies Unit

Description

Spiral galaxies consist of a flattened rotating disk of young stars, a central bulge of generally older stars, and a surrounding halo of older stars and dense clusters of old stars called globular clusters. The disk is prominent due to the presence of young, hot stars often arranged in a spiral pattern. Spiral galaxies are sometimes the hosts of energetic nuclei which emit jets of high-energy particles which are visible in the radio. Images of those objects are categorized separately under the heading Active Galactic Nuclei, most often in the Seyferts sub-catagory.

Collection Items

Molecular and Atomic Gas in IC 342
Description: An optical image of the nearby barred spiral galaxy IC 342 (shown in blueish-white) with overlays in red to show the location of its atomic hydrogen, and in green to show the location of its cool molecular gas (traced by emission from the carbon…

Neutral Gas Disk of the Milky Way
Description: This figure shows the distribution of atomic hydrogen at all locations in the sky. All of this hydrogen is in our galaxy. Red indicates directions of high hydrogen density, blue and black show areas with little hydrogen. The figure is centered on the…

Melco Antennas
Description: In addition to the up to 32 twelve meter antennas supplied by AUI/NRAO and the up to 32 twelve meter antennas supplied by ESO, NAOJ is supplying four twelve meter antennas and twelve 7m antennas. Here the first three twelve meter antennas, built by…

Hydrogen Halo
Description: Using the Green Bank Telescope, a cross-section of the Milky Way Galaxy's diffuse halo of hydrogen gas has been produced. This image confirms the presence of discrete hydrogen clouds in the halo, and could help astronomers understand the origin and…

Galactic Building Blocks Around Andromeda (M31)
Description: Green Bank Telescope 21 cm observations have revealed a faint, yet extensive atomic hydrogen (HI) cloud population surrounding the Andromeda galaxy (M31). This image depicts several long-sought galactic "building blocks" in orbit of the Andromeda…

M33 Motion Graphic
Description: M33's motion in space, relative to M31 and the Milky Way

HI Disk of NGC 2403
Description: NGC 2403 is a well-known spiral galaxy in the northern sky. Galaxies such as NGC 2403 contain, apart from billions of stars that are visible in the right image, a large disk of hydrogen gas. This gas emits radio waves that can be detected with radio…

Radio/Optical Composite of M51
Description: Three separate sets of observations are involved in this composite image of the spiral galaxy M51, also known as the "Whirlpool Galaxy". The optical image (depicted by green and yellow colors in the above image) highlights the younger stars, as well…

The Whirlpool Galaxy
Description: This image of the spiral galaxy M51, also known as the "Whirlpool Galaxy," and its companion NGC5195 combines observations of neutral Hydrogen emission obtained with the Very Large Array with optical images (R, B) from the Second Palomar Observatory…

Atomic Hydrogen in M81
Description: The galaxy M81 is a spiral galaxy about 11 million light-years from Earth. It is about 50,000 light-years across. In the optical (not shown), the galaxy is known as a "Grand Design" spiral, for its pair of symmetric, well-defined spiral arms. This…

The Galactic Plane in Radio
Description: A section of the Galactic plane as seen in the radio is shown both as the sky and also rendered as a height-map on the ground, with the height of the "mountains" representing the brightness of the radio sky. The radio observations were part of a…

Star Formation in NGC 3596
Description: Where does global star formation end in spiral galaxies? The above multi-wavelength image of NGC3596 combines H alpha emission (red), visible light in the R-band (white), and HI 21cm gas emission (blue). The H alpha and R-band data were obtained with…

Star Formation in NGC 1187
Description: Where does global star formation end in spiral galaxies? The above multi-wavelength image of NGC1187 combines H alpha emission (red), visible light in the R-band (white), and HI 21cm gas emission (blue). The H alpha and R-band data were obtained with…

HI Emission Around Spiral Edge-On Galaxy UGC10043.
Description: The image is centered in the spiral edge-on galaxy UGC10043 and its neighbour MCG +04-37-035, which are at a distance of ~32 Mpc from us and appear to be independent objects in the optical band, but are found to be physically connected by hydrogen…

HI Nearby Galaxy Survey (THINGS)
Description: This image shows an HI composite of all galaxies observed as part of The HI Nearby Galaxy Survey (THINGS). All galaxies are shown on the same physical scale and the color indicates HI surface brightness; all galaxies have been observed using the same…

Magnetic Field Structure in the Nearby Starburst Galaxy NGC253
Description: Our best information about magnetic fields in other galaxies is obtained by studying the radio-wavelength synchrotron radiation emitted by cosmic-ray electrons as they move through a galaxy's magnetic field. In this image, radio data from the NRAO…

Magnetic Field Lines in M51
Description: The total radio continuum emission from the "whirlpool" galaxy M51 (distance estimates range between 13 and 30 million light years) is strongest at the inner edges of the optical spiral arms, probably due to the compression of magnetic fields by…

NGC 4438: A Galaxy in Trouble
Description: The galaxy NGC4438 in the Virgo cluster of galaxies seems to be undergoing a terrible time. The northern early-type galaxy has interacted with it in the past and has severely disturbed the stellar disk(shown in white light from Digitalized Sky…

HI + Optical Image of the Integral Sign Galaxy (UGC 3697)
Description: Composite image of the "Integral Sign'' galaxy, UGC 3697. This edge-on spiral galaxy displays an unusually pronounced warp in both its stellar and gaseous disks. The neutral Hydrogen gas, represented in blue, is overlaid on an optical image of the…

Hydrogen Gas Disk in M33
Description: The distribution of the cold neutral atomic hydrogen gas in the Scd galaxy Messier 33, also known as the "Triangulum Galaxy". Bright regions indicate regions with a high gas density, while dark regions have little or no gas. The underlying stellar…

Rotating Disk of M33
Description: A false color representation of the velocity field for the Scd galaxy Messier 33, also known as the "Triangulum Galaxy". The velocities are inferred from observations of the atomic hydrogen gas in the disk of this galaxy. This gas emits light at a…

M33 in Radio and Optical
Description: This image of the Triangulum Galaxy was created by combining optical data from the National Science Foundation's 0.9-meter telescope on Kitt Peak in Arizona with radio data from the National Science Foundation's Very Large Array (VLA) telescope in…

Collection Tree