Universe  ID: 11109

X-ray Satellites Monitor the Clashing Winds of a Colossal Binary

One of the nearest and richest OB associations in our galaxy is Cygnus OB2, which is located about 4,700 light-years away and hosts some 3,000 hot stars, including about 100 in the O class. Weighing in at more than a dozen times the sun's mass and sporting surface temperatures five to ten times hotter, these ginormous blue-white stars blast their surroundings with intense ultraviolet light and powerful outflows called stellar winds.

Two of these stars can be found in the intriguing binary system known as Cygnus OB2 #9. In 2011, NASA's Swift satellite, the European Space Agency's XMM-Newton observatory and several ground-based facilities took part in a campaign to monitor the system as the giant stars raced toward their closest approach. The observations are giving astronomers a more detailed picture of the stars, their orbits and the interaction of their stellar winds.

An O-type star is so luminous that the pressure of its starlight actually drives material from its surface, creating particle outflows with speeds of several million miles an hour. Put two of these humongous stars in the same system and their winds can collide during all or part of the orbit, creating both radio emission and X-rays.

In 2008, research showed that Cygnus OB2 #9 emitted radio signals that varied every 2.355 years. In parallel, Yael Naz



For More Information



Scott Wiessinger (USRA): Lead Animator
Scott Wiessinger (USRA): Video Editor
Scott Wiessinger (USRA): Narrator
Scott Wiessinger (USRA): Producer
Stefan Immler (UMCP): Scientist
Francis Reddy (Syneren Technologies): Writer
Scott Wiessinger (USRA): Writer
Please give credit for this item to:
NASA/Goddard Space Flight Center. However, individual images should be credited as indicated above.

Science Paper:

Short URL to share this page:


Data Used:
Note: While we identify the data sets used in these visualizations, we do not store any further details nor the data sets themselves on our site.

This item is part of these series:
Astrophysics Simulations
Astrophysics Stills
Astrophysics Features

Goddard TV Tape:
G2012-102 -- Colliding Winds-Cyg OB2

SVS >> Music
SVS >> Solar Wind
SVS >> X-ray
SVS >> Astrophysics
SVS >> Edited Feature
SVS >> Swift
SVS >> Binary Star
DLESE >> Narrated
SVS >> XMM-Newton observatory
SVS >> Star
NASA Science >> Universe