Astronomers have made an important
advance
in the understanding how clusters of
stars like our sun
form, using data from NASA's Chandra X-ray Observatory
and infrared telescopes. The data show
early notions of how star clusters are
formed cannot be correct.
The simplest idea is stars form
into clusters when a giant cloud of gas
and dust condenses.
The center of the cloud pulls in
material from its surroundings
until it becomes dense enough to trigger
star formation.
This process occurs in the center the
cloud first,
implying that the stars in the middle of
the cluster form first,
and, therefore, are the oldest. These new
results suggest something else is
happening.
By studying two clusters where sun-like stars are forming -- 
NGC 2024, located in the center
the Flame Nebula, and the Orion Nebula
Cluster --
researchers have discovered the stars on
the outskirts of the clusters
are actually the oldest.
The researchers will use this same
technique of combining X-rays
and infrared data to study the age range in
other clusters.
In the meantime, scientists will be hard
at work
to develop other, more complex ideas to
explain what they've seen
in NGC 2024 in the Orion Nebula Cluster.
