Magic mirrors:
making the
atmosphere
disappear

Deformable surface

The adaptive secondary mirror surface can reshape 1,000 times per second using the world’s most advanced wavefront sensors and algorithms to correct for the optical blurring effect of Earth’s atmosphere.

Small and thin

Adaptive secondary mirrors have a glass-like Zerodur surface that is flexible because of its 1.05 meter diameter and 2 millimeter thickness.

Powered by magnets

To control the shape of the adaptive secondary mirror, 675 magnets are bonded to the back of the mirror that are pushed or pulled on by electromagnetic actuators.

Internal metrology

The 150 micron (thickness of 3 human hairs) air gap between the mirror surface and its frame is used to form a capacitive sensor to help measure its alignment and adjust how the mirror’s surface must adapt to incoming light.

Seven pack match

Each adaptive secondary mirror is paired and aligned with only one of the giant seven primary mirrors and is responsible for receiving the distorted light reflected from this primary mirror.

Revolution in Resolution

agosto 14, 2018

Excavation Begins on Giant Magellan Telescope Site in Chile

News

24.5 M

is the total area of the primary mirrors. The primary mirror will be comprised of seven separate 8.4 meter (27 foot) diameter segments.

<10G

The thickness of the aluminium film that the mirrors are coated with is just a few atoms. Thus the huge mirror needs just a few grams of aluminium for the coat.

17 TONS

is the total weight of the mirrors. It is a borosilicate glass with a very low, and very uniform, rate of thermal expansion.