The Spiral Galaxy M100 as Seen With the Hubble's Improved Vision

 The Spiral Galaxy M100 as Seen With the Hubble's Improved Vision

An image of the grand design spiral galaxy M100 obtained with the second generation Wide Field and Planetary Camera (WFPC-2), newly installed in the Hubble Space Telescope. Though the galaxy lies several tens of millions of light-years away, modified optics incorporated within the WFPC-2 allow Hubble to view M100 with a level of clarity and sensitivity previously possible only for the very few nearby galaxies that compose our "Local Group." Just as one does not learn about the diversity of mankind by conversing only with your next door neighbor, astronomers must study many galaxies in a host of different environments if they are to come to understand how our own galaxy, out star, and our earth came to be. By expanding the region of the universe that can be studied in such detail a thousand fold, the WFPC-2 will help the Hubble Space Telescope to fulfill this mission.

One of the greateset gains of the high resolution provided by Hubble is the Ability to resolve individual stars in other galaxies. The new camera not only allows astronomers to separate stars which would have been blurred together at the resolution available from the ground, but also allows astronomets to accurately measure the light form very faint stars. The quantitative study of compositions, ages, temperatures, and other properties of stars and gas in other galaxies will provide important clues about how galaxies form and evolve.

In addition, the WFPC-2 will allow the Hubble Space Telescope to be used to attack one of the most fundamental questions in science: the age and scale of the universe. Astronomers have many "yardsticks" for measuring the scale of the universe, but lack a good knowledge of how long these yardsticks really are. M100 is a member of the Virgo Cluster of galaxies. By allowing astronomers to resolve and measure individual stars in the Virgo Cluster - in particular a special type of star called Cepheid variables, which have well known absolute brightnesses - HST observations are expected to provide a crucial measurement of this much needed scale. (Only Space Telescope can make these types of observations. Cepheids are too faint and the resolution too poor, as seen from ground-based telescope, to separate the images in such a crowded region of a distance galaxy.)

The picture is chevron-shaped because it is a mosaic of the three wide field cameras and the planetary camera which make up the WFPC-2. The three wide field detectors in the camera reveal individual stars and filamentary dust lanes in the outer arms of the majestic spiral galaxy. The instrument's planetary camera image (upper right) resolved complex structure in the core of the galaxy, which is the site of vigorous star formation.

The image was taken on December 31, 1993. The field of view is about two and a half arc minutes across. The image aws taken through red, green, and blue filters to create a true color picture. Blue corresponds to the light from yound and massive stars that have recently formed along the spiral arms. The pinkish blobs are huge blouds of glowing hydrogen gas. They indentify sites of new star formation.

Credits

NASA, STScI

About The Object
Object Name M100, NGC 4321
R.A. Position 12h 22m 54.94s
Dec. Position 15° 49' 19.49"
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.