Spark image


The angle between mirror 2 and the telescope is 6 0o. One half of this mirror is silvered and the other half is clear glass. Mirror M1 is completely silvered and can be rotated on the arm M1V. When the arm is in position O the two mirrors are parallel to each other.

Light coming from one object (B) makes an angle of Ao with light coming from another object (C). Direction B could be the horizon and direction C the Sun or a star.
© Keith Gibbs 2013