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t he brightest stars do not live alone. B ackground Design E. Buunk / S.E. de Mink, HST image: NASA Paresce. Selma E. de Mink Hubble Science Briefing , February 7, 2013 Hubble Fellow at Space Telescope Science Institute / Johns Hopkins University. t he brightest stars .
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the brightest stars do not live alone Background Design E. Buunk / S.E. de Mink, HST image: NASA Paresce Selma E. de Mink Hubble Science Briefing , February 7, 2013 Hubble Fellow at Space Telescope Science Institute / Johns Hopkins University
the brightest stars are up to a million times brighter than the Sun are rare Background Design E. Buunk / S.E. de Mink, HST image: NASA Paresce live fast and die young are embedded in clouds of gas & dust are very hard to study 2
This is what we thought … Massive Stars* BOOM Low-mass Stars *8-150 times more massive than the sun …. but it turns out that it is not that simple 3
The Sun is a single star If the Sun were the size of a baseball … … in Yankee stadium… … the nearest star would be in Houston, TX (1,400 mi. away) 5
many stars are quite unlike the Sun Artist impression: (ESO/L. Calçada/Nick Risinger) Alpha Centauri, our nearest neighbor, is a multiple system: Star A & B orbit each other every 80 years 6
another famous multiple Alcor & Mizar Image Credit: ESO Online Digitized Sky Survey 7
3 binaries forming a sextuple system Alcor A & B Mizar A: a & b Mizar B: a & b A Spectroscopic binary Zimmerman et al. 2009 Image Credit: ESO Online Digitized Sky Survey Mizar A & B 8
Classic definition Binary System = a system of two objects in space (usually stars), which are so close that their gravitationalinteraction causes them to orbitaround their common center of mass. According to this definition, almost all stars are binaries(or multiples). The Sun is one of the exceptions. 9
Not every binary is equal • Close Binary System • Closer than the distance from the Sun to Mars. • One orbit takes between a day and few years. • Wide Binary System • Widerthan the distance from the Sun to Jupiter. • One orbit takes a few years up to centuries or more. 10
A typical star becomes about 100-1000 times bigger during its life … 12
= Therefore, stars in close binary systems will interact 13
Artist Illustration of a “vampire star system”: ESO: Calçada/Kornmesser/de Mink 14
What % of massive stars will interact 22 Sana & de Mink et al. Science, Cartoons: de Mink / Buunk
It is not this simple … Massive Stars* BOOM Low-mass Stars See video: http://hubblesite.org/newscenter/archive/releases/2012/33/video/b/ 23
Conclusion 26
the brightest stars do not live alone Background Design E. Buunk / S.E. de Mink, HST image: NASA Paresce Science 27 July 2012: Vol. 337 no. 6093 pp. 444-446 Selma E. de Mink More information: http://hubblesite.org/newscenter/archive/releases/2012/33/full/