Apollo 11 Astronaut Buzz Aldrin is seen setting up scientific instruments on the moon. They include a seismometer to measure moonquakes and a mirror array to measure the distance between the Earth and moon. The lunar lander and an American flag can be seen in the background. Those items also were left on the moon.

The bending of starlight caused by Earth’s atmosphere could be used to create a giant telescope, one scientist suggests. It would require placing a detector out in space (illustrated).

There are hypothetical dark matter particles called “macros.” Macros might stream through space and constantly bombard Earth. Some could seriously injure any unlucky humans they pass through. But a lack of mysterious deaths suggests the biggest potential macros don’t exist.

Small enough to fit on a table, this mini Kibble balance measures smaller units of mass, such as a few grams, with amazing accuracy. A Lego figurine perched on the top right holds a 1-gram mass for scale.