Lasers for Space Broadband

Speeds of 622 Mbps from the moon:

Wireless broadband service went cosmic in a demo conducted by the Massachusetts Institute of Technology’s (MIT) Lincoln Laboratory and NASA, in which a laser-based communication uplink between the moon and earth beat the previous record transmission speed by a factor of 4,800.

The team’s Lunar Laser Communication Demonstration (LLCD) transmitted data over the 384,633 kilometers between the moon and earth at a download rate of 622 Mbps. In addition, data was transmitted from the earth to the moon at 19.44 Mbps, a factor 4,800 times faster than the best radio-frequency uplink ever used, MIT said.

Other moon-laser applications here:

Alert the Queen!

Via What-If xkcd:

When (if ever) did the Sun finally set on the British Empire?

—Kurt Amundson

It hasn’t. Yet. But only because of a few dozen people living in an area smaller than Disney World.

The world’s largest empire

The British Empire spanned the globe. This led to the saying that the Sun never set on it, since it was always daytime somewhere in the Empire.

It’s hard to figure out exactly when this long daylight began.  The whole process of claiming a colony (on land already occupied by other people) is awfully arbitrary in the first place. Essentially, the British built their empire by sailing around and sticking flags on random beaches.[1] This makes it hard to decide when a particular spot in a country was “officially” added to the Empire.

Every night, around midnight GMT, the Sun sets on the Cayman Islands, and doesn’t rise over the British Indian Ocean Territory until after 1:00 AM. For that hour, the little Pitcairn Islands in the South Pacific are the only British territory in the Sun.

But not forever. Eventually—many millennia in the future—an eclipse will come for the island, and the Sun will finally set on the British Empire.

More here.