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A 15-MSUN star that has been monitored for decades is found to be orbiting in a highly eccentric ellipse about an unseen mass (presumably a supermassive black hole) at the center of Milky Way with a period of 15.6 years and a semimajor axis of about 1,000 AU.What is the mass of the unseen object?
Pupil Dilation
The expansion of the pupil of the eye, which can occur due to various factors, including emotional arousal, changes in light, or the influence of certain drugs.
Color Receptors
Specialized cells in the retina of the eye, called cones, that are sensitive to different wavelengths of light, enabling color vision.
Hermann Von Helmholtz
A German physicist and physician known for his contributions to the understanding of the conservation of energy, optics, and acoustics.
Thomas Young
A British polymath known for his contributions to the fields of vision, light, solid mechanics, energy, physiology, and language.
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