starbust galaxy

NASA’s Hubble Space Telescope has imaged one of the most active galaxies in our local neighborhood. NGC 1569, sparkles with the light from millions of newly formed young stars. At the nucleus of the starburst galaxy is a grouping of three giant star clusters, each containing more than a million stars. The clusters reside in a large, central cavity. The gas in the cavity has been blown out by the multitude of massive, young stars that already exploded as supernovae. NGC 1569 is located 11 million light-years from Earth in the constellation Camelopardalis. Hubble’s Wide Field Planetary Camera 2 and Advanced Camera for Surveys made the observations of NGC 1569 in September 1999, November 2006, and January 2007. This image shows the full region that was imaged by both detectors.

Object Name: NGC 1569

Image Type: Astronomical

Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA), and A. Aloisi (STScI/ESA)

Time And Space

Nicknamed the Southern Pinwheel, M83 is undergoing more rapid star formation than our own Milky Way galaxy, especially in its nucleus. The sharp “eye” of the Wide Field Camera 3 (WFC3) has captured hundreds of young star clusters, ancient swarms of globular star clusters, and hundreds of thousands of individual stars, mostly blue supergiants and red supergiants.

WFC3’s broad wavelength range, from ultraviolet to near-infrared, reveals stars at different stages of evolution, allowing astronomers to dissect the galaxy’s star-formation history.

The image reveals in unprecedented detail the current rapid rate of star birth in this famous “grand design” spiral galaxy. The newest generations of stars are forming largely in clusters on the edges of the dark dust lanes, the backbone of the spiral arms. These fledgling stars, only a few million years old, are bursting out of their dusty cocoons and producing bubbles of reddish glowing hydrogen gas.

The excavated regions give a colorful “Swiss cheese” appearance to the spiral arm. Gradually, the young stars’ fierce winds (streams of charged particles) blow away the gas, revealing bright blue star clusters. These stars are about 1 million to 10 million years old. The older populations of stars are not as blue.

A bar of stars, gas, and dust slicing across the core of the galaxy may be instigating most of the star birth in the galaxy’s core. The bar funnels material to the galaxy’s center, where the most active star formation is taking place. The brightest star clusters reside along an arc near the core.

The remains of about 60 supernova blasts, the deaths of massive stars, can be seen in the image, five times more than known previously in this region. WFC3 identified the remnants of exploded stars. By studying these remnants, astronomers can better understand the nature of the progenitor stars, which are responsible for the creation and dispersal of most of the galaxy’s heavy elements.

M83, located in the Southern Hemisphere, is often compared to M51, dubbed the Whirlpool galaxy, in the Northern Hemisphere. Located 15 million light-years away in the constellation Hydra, M83 is two times closer to Earth than M51.

Object Name: M83

Image Type: Astronomical

Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA), R. O'Connell (University of Virginia) and the Wide Field Camera 3 Science Oversight Committee

Time And Space