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Exploring our Solar System and unlocking the secrets of the Universe
Go to topicProtecting life and infrastructure on Earth and in orbit
Go to topicUsing space to benefit citizens and meet future challenges on Earth
Go to topicMaking space accessible and developing the technologies for the future
Go to topicThis computer simulation shows the gas density around a colliding wind binary named WR 22. The star locations are marked by yellow dots, and decreasing gas density is indicated by the sequence of red, white and blue colours. In this simulation, a 26 solar mass O-type star orbits the hotter and more massive 72 solar mass Wolf-Rayet star WR 22. During closest approach, the more massive star's stellar wind is so intense that the collision region is forced back onto the O star. Such a collapse of the wind region does not occur with Cygnus OB2 #9, which makes it a well-behaved and important example of wind-wind interactions.
Credits: University of Liège/Australian National University/E. R. Parkin and E. Gosset.