A photogenic and favorite target for amateur astronomers, the full
beauty of nearby spiral galaxy M83 is unveiled in all of its glory in
this Hubble Space Telescope mosaic image. The vibrant magentas and
blues reveal the galaxy is ablaze with star formation. The galaxy, also
known as the Southern Pinwheel, lies 15 million light-years away in
the constellation Hydra.
The Hubble photograph captures thousands of star clusters, hundreds
of thousands of individual stars, and "ghosts" of dead stars called
supernova remnants. The galactic panorama unveils a tapestry of the
drama of stellar birth and death spread across 50,000 light-years.
The newest generations of stars are forming largely in clusters on
the edges of the dark spiral dust lanes. These brilliant young stellar
groupings, only a few million years old, produce huge amounts of
ultraviolet light that is absorbed by surrounding diffuse gas clouds,
causing them to glow in pinkish hydrogen light.
Gradually, the fierce stellar winds from the youngest, most massive
stars blow away the gas, revealing bright blue star clusters and giving
a "Swiss Cheese" appearance to the spiral arms. These youngest star
clusters are about 1 million to 10 million years old. The populations
of stars up to 100 million years or older appear yellow or orange by
comparison because the young blue stars have already burned out.
Interstellar "bubbles" produced by nearly 300 supernovas from massive
stars have been found in this Hubble image. By studying these
supernova remnants, astronomers can better understand the nature of the
stars that exploded and dispersed nuclear processed chemical elements
back into the galaxy, contributing to the next generation of new stars.
This image is being used to support a citizen science project titled
STAR DATE: M83. The primary goal is to estimate ages for approximately
3,000 star clusters. Amateur scientists will use the presence or
absence of the pink hydrogen emission, the sharpness of the individual
stars, and the color of the clusters to estimate ages. Participants
will measure the sizes of the star clusters and any associated emission
nebulae. Finally, the citizen scientists will "explore" the image,
identifying a variety of objects ranging from background galaxies to
supernova remnants to foreground stars.
STAR DATE: M83 is a joint collaborative effort between the Space
Telescope Science Institute and Zooniverse, creators of several citizen
science projects including Galaxy Zoo, Planet Hunters, and the
Andromeda Project (go to www.zooniverse.org to see the full list). The
M83 project is scheduled to launch on Monday, January 13, 2014. People
interested in exploring this remarkable image in more detail, and in
directly participating in a science project, can visit http://www.projectstardate.org .
Source: HubbleSite
