The mirrors for X-ray telescopes are the same shape as those of optical reflectors.
Indicate whether the statement is true or false
Question 2
Why is a dense cloud more likely to produce an elliptical galaxy than a spiral galaxy?
A) The higher density of gas has a stronger force of gravity, and therefore the cloud collapses more quickly.
B) The thickness of the dense cloud prevents a disk from forming.
C) The higher gas density forms stars more efficiently, so all the gas is converted into stars before a disk can form.
D) The force of gravity can pull the material into a more spherical shape.
E) The more frequent collisions between particles randomize the particle orbits.
Classification of bones by shape.
Taken by Hinode's Solar Optical Telescope on January 12, 2007, this image of the Sun reveals th
Optical biopsy.
Bones change radically in size and shape from newborn to adult, as these cervical vertebrae demonstr
optical illusions
Optical Illusion