Westerlund 2

 Westerlund 2

Celestial Fireworks in Westerlund 2

The brilliant tapestry of young stars flaring to life resemble a glittering fireworks display in this Hubble Space Telescope archival image.

The sparkling centerpiece of this fireworks show is a giant cluster of thousands of stars called Westerlund 2. The cluster resides in a raucous stellar breeding ground known as Gum 29, located 20,000 light-years away from Earth in the constellation Carina.

Hubble's Wide Field Camera 3 pierced through the dusty veil shrouding the stellar nursery in near-infrared light, giving astronomers a clear view of the nebula and the dense concentration of stars in the central cluster. The cluster measures between 6 light-years and 13 light-years across.

The giant stellar grouping is only about 2 million years old and contains some of our Milky Way galaxy's hottest, brightest, and most massive stars. Some of its heftiest stars unleash torrents of ultraviolet light and hurricane-force winds of charged particles that etch away the enveloping hydrogen gas cloud. New Hubble observations are showing that lower-mass stars near the cluster's core do not have the large, dense clouds of dust that eventually could become planets in a few million years. Hubble detected those planet-forming clouds embedded in disks encircling lower-mass stars farther away from the center.

The nebula reveals a landscape of pillars, ridges, and valleys. The pillars, composed of dense gas and thought to be incubators for new stars, are a few light-years tall and point to the central star cluster. Other dense regions surround the pillars, including reddish-brown filaments of gas and dust. The red dots scattered throughout the landscape are a rich population of newly forming stars still wrapped in their gas-and-dust cocoons. The brilliant blue stars seen throughout the image are mostly foreground stars.

The image's central region, which contains the star cluster, blends visible-light data taken by Hubble's Advanced Camera for Surveys with near-infrared exposures taken by the Wide Field Camera 3. The surrounding region is composed of visible-light observations taken by the Advanced Camera for Surveys. The red colors in the nebulosity represent hydrogen; the bluish-green hues are predominantly oxygen.

Credits

NASA, ESA, the Hubble Heritage Team (STScI/AURA), A. Nota (ESA/STScI), and the Westerlund 2 Science Team

About The Object
Object Name Westerlund 2, Gum 29
Object Description Cluster and Star-forming region
R.A. Position 10h 23m 58.1s
Dec. Position -57° 45' 48.96"
Constellation Carina
Distance 20,000 light-years (6,130 parsecs)
About The Data
Data Description Data of Westerlund 2 were obtained from the HST proposals : A. Nota (ESA/STScI), E. Sabbi and C. Christian (STScI), E. Grebel and P. Zeidler (Astronomisches Rechen-Institut, Zentrum für Astronomie der Universität Heidelberg), M. Tosi (INAF, Osservatorio Astronomico di Bologna), A. Bonanos (National Observatory of Athens, Astronomical Institute), and S. de Mink (University of Amsterdam); and : Z. Levay, M. Mutchler, J. Mack, L. Frattare, S. Meyett, M. Livio, and C. Christian (STScI/AURA), K. Noll (NASA/GSFC), A. Nota (STScI/ESA), and E. Sabbi (STScI).
Instrument HST>ACS/WFC and HST>WFC3/IR
Exposure Dates September 2013 - November 2014, Total Exposure Time: 23,074 seconds
Filters ACS/WFC: F555W (V) and F814W (I) WFC3/IR: F125W (J)
About The Image
Color Info These images are composites of separate exposures acquired by the ACS and the WFC3 instruments on the Hubble Space Telescope. Several filters were used to sample broad and narrow wavelength ranges. The color results from assigning different hues (colors) to each monochromatic (grayscale) image associated with an individual filter. In this case, the assigned colors are: Edge/Nebula Blue: F555W (V) Green: F555W (V) and F814W (I) Red: F814W (I) Central portion of Westerlund 2 Cluster Blue: F555W (V) Green: F814W (I) Red: F125W (J)
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.