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The NASA / ESA
Hubble Space Telescope

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has captured a spectacular
image of NGC 3603,

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a giant nebula hosting
one of the most prominent

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massive young clusters
in the Milky Way.

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This is a splendid location for
continuing our detailed study

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of stellar birth
in star forming regions.

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This is the Hubblecast.

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News and images from the
NASA / ESA Hubble Space Telescope.

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Travelling through time and space
with our host, Dr. J

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EPISODE 9: Extreme star cluster
bursts into life!
a.k.a. Dr. Joe Liske.

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Welcome to the Hubblecast.

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Today we are going to travel

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to the heart of a massive
cluster of young stars

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that lies deep inside
a vast nebula of gas and dust.

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The nebula
is called NGC 3603

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and it is located about
20,000 light years from Earth

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in the Carina spiral arm of
our own Milky Way galaxy.

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Now turns out that the nebula

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is actually the nursery
of a star cluster.

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It is thought that
the nebula contains

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hundreds of thousands
of solar masses worth of gas,

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and only about
one million years ago

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some of that gas
collapsed in on itself

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and formed probably all
of the stars in the cluster

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at more or less the same time

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in a massive burst
of star formation.

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Today we see the result as
a glittering collection of stars

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surrounded by a dense cloud
of hydrogen gas.

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In this new detailed
image from Hubble

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we can see thousands
of young blue stars

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sparkling against
their maternal nebula.

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But this is not as tranquil
a place as you might think.

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Some of the action
is still going on.

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The strong
ultraviolet radiation

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and the winds from
these newborn stars

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are shaping and sculpting
the surrounding gas,

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carving out a huge cavity
into the nebula.

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A team of astronomers

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was able to use
the Hubble Space Telescope

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to peer into the hearth
of the star forming region

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which was first observed in 1834
by Sir John Herschel,

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the son of the world-renowned
astronomer Sir William Herschel.

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They were able to make
detailed observations of stars

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whose masses differ
but whose ages are similar.

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Because of this fact astronomers
were able to study a wide range

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of stars at different points
in their respective life cycles

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and make comparisons with
other similar star clusters.

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The new Hubble image is full
of interesting objects

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for astronomers to study.

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Here, at the top right
of the image

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we see a handful
of Bok globules.

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These objects were
first observed in the 1940s

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by astronomer Bart Bok.

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They are some of the coldest
objects in the Universe

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and they are dense clouds
of gas and dust

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of around ten to fifty
solar masses

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and they are collapsing
to form new stars.

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Around the cluster, near the
densest part of the nebula

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we see these
huge pillars of gas

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pointing away from
the cluster's core.

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These were shaped by the
massive young cluster's stars

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and eventually they will be
dispersed into interstellar space.

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One of the most interesting
objects in the image

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is this seemingly
innocuous bright star.

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This star is designated
Sher 25

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and it is actually
a blue super giant

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nearing the very end
of its life.

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Astronomers think that
in the not too distant future

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Sher 25 will explode
as a tremendous event

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like supernova 1987A
which has been observed

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by Hubble on many occasions.

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In doing so it will seed space
with the heavy elements

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necessary for planet formation.

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Perhaps it will even trigger
a new wave of star formation

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in the nearby nebula.

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For now though astronomers
using the Hubble

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are interested in the stars
within the massive young cluster

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at the heart of NGC 3603.

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Several stars
at the cluster's core

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have caused astronomers
to be deceived.

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The huge stars in the innermost
regions of the cluster

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appear to be far more massive

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than our current
theoretical limits dictate.

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Nothing escapes the sharp
eye of Hubble though

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as it was able to show
that these stars are in fact

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the light from several
stars blended together.

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They appear as one star
but are actually composed of

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two or even three components.

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This agrees well with
previous observations

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of this apparently "heavy-weight"
objects as composed of

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several stars of around
80 to 120 solar masses each.

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The new Hubble image
is full of amazing detail.

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Not only are we seeing
a whole cluster of stars

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just one million years
after its birth.

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But there's also one star that
is about to go supernova

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in a gigantic explosion
that will be seen

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across large parts
of the Galaxy.

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In NGC 3603 we are
literally seeing the birth

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and death of stars
right before our eyes.

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So, this apparently
picturesque stellar nursery

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is in fact the site of some
pretty extreme astronomy!

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This is Dr. J
signing off for the Hubblecast.

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Once again, nature has surprised us
beyond our wildest imagination...

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Hubblecast is produced
by ESA / Hubble

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at the European
Southern Observatory in Germany.

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The Hubble mission is a project
of international cooperation

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between NASA and
the European Space Agency.