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Rovers Will Unroll a Telescope on the Moon’s Far Side

Astronomers need a quiet place to observe the cosmic dawn

2 min read
Illustration of a rover laying down flexible antenna on the lunar surface.
Illustration: Peter Sanitra

Illustration: Peter Sanitra

The central electronics box would sift and compress signals from the antenna before transmitting data back to Earth via a relay satellite. The equipment will have to withstand extremes of heat and cold during the moon’s month-long day/night cycle.

For decades, astronomers have gazed up at the moon and dreamed about what they would do with its most unusual real estate. Because the moon is gravitationally locked to our planet, the same side of the moon always faces us. That means the lunar far side is the one place in the solar system where you can never see Earth—or, from a radio astronomer’s point of view, the one place where you can’t hear Earth. It may therefore be the ideal location for a radio telescope, as the receiver would be shielded by the bulk of the moon from both human-made electromagnetic noise and emissions from natural occurrences like Earth’s auroras.

Early plans for far-side radio observatories included telescopes that would use a wide range of frequencies and study many different phenomena. But as the years rolled by, ground- and satellite-based telescopes improved, and the scientific rationale for such lunar observatories weakened. With one exception: A far-side telescope would still be best for observing phenomena that can be detected only at low frequencies, which in the radio astronomy game means below 100 megahertz. Existing telescopes run into trouble below that threshold, when Earth’s ionosphere, radio interference, and ground effects begin to play havoc with observations; by 30 MHz, ground-based observations are precluded.

In recent years, scientific interest in those low frequencies has exploded. Understanding the very early universe could be the “killer app” for a far-side radio observatory, says Jack Burns, an astrophysics professor at the University of Colorado and the director of the NASA-funded Network for Exploration and Space Science. After the initial glow of the big bang faded, no new light came into the universe until the first stars formed. Studying this “cosmic dawn [PDF],” when the first stars, galaxies, and black holes formed, means looking at frequencies between 10 and 50 MHz, Burns says; this is where signature emissions from hydrogen are to be found, redshifted to low frequencies by the expansion of the universe.

With preliminary funding from NASA, Burns is developing a satellite mission that will orbit the moon and observe the early universe while it travels across the far side. But to take the next step scientifically requires a far larger array with thousands of antennas. That’s not practical in orbit, says Burns, but it is feasible on the far side. “The lunar surface is stable,” he says. “You just put these things down. They stay where they need to be.”

This article appears in the July 2019 print issue as “The View From the Far Side.”

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Always Break Yolks: The Joy of Microwave Cooking

A homeowner’s intro to microwave oven cuisine, circa 1980

6 min read
A rectangular kitchen appliance with a metal housing, a glass door, and two dials on the righthand side.

In 1975, when this Amana Radarange was introduced, U.S. sales of microwave ovens surpassed those of gas ovens for the first time.

As I write this month’s article, my house is a noisy, dusty construction zone. I am renovating my kitchen, which was originally built in 1964. Although I’m happy to be rid of some of the disastrous 1960s design missteps—seriously, only one electrical receptacle in the entire kitchen?—I was sad to part with a small piece of history: my Amana Touchmatic Radarange microwave oven, with its 700 watts of glorious electromagnetic cooking power.

The ever evolving and revolving microwave oven

My Radarange was installed by the previous homeowner in 1980 and had a decidedly vintage feel, but it was actually a third-generation model. The original Radarange came out in 1947 and was intended for commercial kitchens. Two years prior, Raytheon engineer Percy Spencer had filed a patent for a “Means for Treating Foodstuff,” and the company tested the oven in a Boston restaurant. This water-cooled model was the size of a modest refrigerator, standing approximately 1.7 meters tall and weighing 340 kilograms. It would take a while for the microwave oven to evolve into the countertop version we all know today.

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FAST Labs’ Cutting-Edge R&D Gets Ideas to the Field Faster

BAE Systems’ FAST Labs engineers turn breakthrough innovations into real-life impact

1 min read
Woman uses her hands to operate control system next to man who observes other equipment.

FAST Labs is an R&D organization where research teams can invent and see their work come to life.

BAE Systems

This is a sponsored article brought to you by BAE Systems.

No one sets out to put together half a puzzle. Similarly, researchers and engineers in the defense industry want to see the whole picture – seeing their innovations make it into the hands of warfighters and commercial customers.

That desire is fueling growth at BAE Systems’ FAST Labs research and development (R&D) organization.

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