The most massive and luminous visible → starburst region in the
Galaxy. This is our local → giant H II region lying
at a distance of about 6-7 kpc in the → Carina arm
(→ right ascension = 11h, → declination
= -61°). Its central starburst cluster hosts the
largest known concentration of extremely young,
mostly unevolved → high-mass stars in the Galaxy. With an age of
only 1-2 Myr for its
most massive stars, NGC 3603 is one of the youngest starburst clusters known.
It has about 40 known → O stars
and → W-R stars, producing a → Lyman continuum
flux of 1051 s-1, about 100 times the ionizing
power of the Orion → Trapezium cluster.
The OB stars contribute to more than 2000 → solar masses to the
cluster mass. With a bolometric
luminosity over 107→ solar luminosities, NGC 3603 has
about 10% of the
luminosity of → 30 Doradus and looks in many respects very similar
to its core, → R136. A total mass of 7,000 solar masses is measured in
the inner 1 pc from the cluster center, whereas the → low-mass stars
extend out to at least 5 pc. The mass segregated core of the
cluster, with 105 solar masses per pc3, displays the highest local
stellar density outside the Galactic Center region. The spectral
analysis of the W-R like massive component in the cluster core
(→ HD 97950) suggests a → metallicity
close or equal to solar (See, e.g., Melena et al. 2008, AJ 135, 878, and references
therein).
See also: 3603, a serial number in the → New General Catalogue.
