In the early 20th century, when Henrietta Leavitt began studying photographs of distant stars at the Harvard College Observatory, astronomers had no idea how big the universe was....Leavitt, working as a poorly paid member of a team of mostly women [computers] who cataloged data for the scientists at the observatory, found a way to peer out into the great unknown and measure it.

Leavitt discovered the period-luminosity relationship for Cepheid variable stars. The relationship, now known as Leavitt's Law, is a crucial rung in the cosmic distance ladder, the methods for measuring the distance to stars, galaxies, and across the visible universe.

[Leavitt's Law] underpinned the research of other pioneering astronomers, including Edwin Hubble and Harlow Shapley, whose work in the years after World War I demolished long-held ideas about our solar system’s place in the cosmos. Leavitt’s Law has been used on the Hubble Telescope and the James Webb Space Telescope in making new calculations about the rate of expansion of the universe and the proximity of stars billions of light years from earth.

“She cracked into something that was not only impressive scientifically but shifted an entire paradigm of thinking....”

On Friday, Earth’s haunting silence will come to an end as NASA switches that communications channel back on, restoring humanity’s ability to say hello to its distant explorer.

Because of the direction in which it is flying out of the solar system, Voyager 2 can only receive commands from Earth via one antenna in the entire world. It’s called DSS 43 and it is in Canberra, Australia. It is part of the Deep Space Network, or DSN, which along with stations in California and Spain, is how NASA and allied space agencies stay in touch with the armada of robotic spacecraft exploring everything from the sun’s corona to the regions of the Kuiper belt beyond the orbit of Pluto. (Voyager 2’s twin, Voyager 1, is able to communicate with the other two stations.)

A round-trip communication with Voyager 2 takes about 35 hours — 17 hours and 35 minutes each way....

While Voyager 2 was able to call home on the Canberra site’s smaller dishes during the shutdown, none of them could send commands to the probe....

NASA ... did send one test message to the spacecraft at the end of October when the antenna was mostly reassembled.

On June 7, 1954, Alan Turing, a British mathematician who has since been acknowledged as one the most innovative and powerful thinkers of the 20th century — sometimes called the progenitor of modern computing — died as a criminal, having been convicted under Victorian laws as a homosexual and forced to endure chemical castration. Britain didn’t take its first steps toward decriminalizing homosexuality until 1967.

Only in 2009 did the government apologize for his treatment.