Open Star Clusters M35 and NGC 2158

Open Star Clusters M35 and NGC 2158

Image Credit &
Copyright:

Evan Tsai,
LATTE: Lulin-ASIAA Telescope

Explanation:

Framed in this
single, starry, telescopic field of view
are two open star clusters, M35 and NGC 2158.

Located within the boundaries of the
constellation Gemini, they
do appear to be side by side.

Its stars concentrated toward the upper right,
M35 is relatively nearby, though.

M35 (also cataloged
as NGC 2168) is a mere 2800 light-years
distant, with 400 or so stars spread out over a volume
about 30 light-years across.

Bright blue stars frequently distinguish younger open clusters like
M35,
whose age is estimated at 150 million years.

At lower left,
NGC 2158
is about four times more distant than M35
and much more compact, shining with the more yellowish light
of a population
of stars
over 10 times older.

In general, open star clusters are found along the plane of our
Milky Way Galaxy.

Loosely gravitationally bound, their member stars
tend to be dispersed
over billions of years as the open star clusters orbit the galactic center.