Microlensing Light Curve for Stellar Objects

closest projected approach

u

0

0.07

relative angular motion

Einstein ring radius

= c

1

farthest ± time displayed T

2

height of graph z

25

Gravitational microlensing is a phenomenon in which a compact, massive foreground object (the lens) bends the light of a background object (the source, such as a star or galaxy) so that multiple images of the source can be seen. If the source travels close enough to the lens in the sky, there is a chance of observing a microlensing event, during which the brightness of the source, and therefore of the entire system, increases for a brief period. This interactive graph shows the light curve of such an event, based on various parameters of the system.