Science picture of the month
Science picture of the month

Massive star formation

image

Legend:

Contour lines=Gas-density
Colors=Temperature

Description:
In the related research project (MSF), we investigate the role of the radiation pressure onto the formation of massive stars. Potentially, the strong radiation pressure of a massive star inhibits further accretion onto its surface; such an intrinsic process would e.g. give an upper mass limit for stars in general.
The image illustrates a snapshot of a high-resolution radiation hydrodynamics simulation of the collapse of a pre-stellar core of cold gas and dust of 120 solar masses. In the center of the core, a new star is born during the free-fall epoch of the collapsing core. Afterwards the newborn star gains further mass from an accretion disk, which formed due to angular momentum conservation from the initially slowly rotating core.
After some while, the luminosity of the massive star has increased so much, that the resulting radiation pressure drags the in-falling mass from the bipolar direction into outer space. The concentrated opaque density of the accretion disk (the blue region) hampers the radiation pressure in this midplane layer at this point in time.
At the point when the accretion from the envelope region onto the disk has sufficiently decreased, the accretion disk looses its opaqueness and without this shielding effect the radiation pressure of the star starts to clear also the midplane layer.
In the end, the final star has accreted approximately 56.5 solar masses.

Authors:
Rolf Kuiper

More information:
Homepage of the author
Scientific background
YouTube channel

Old pictures of the month

Page last modified on 26.02.2010.
Please send questions and comments about this page to webmaster.