Skip to Content
Uncategorized

Astronomers Plan Galaxy-Sized Observatory For Gravitational Waves

An array of pulsars should shimmer as gravitational waves wash over it, making a galaxy-sized observatory

Gravitational waves squash and stretch space as they travel through the universe. Current attempts to spot them involve monitoring a region of space several kilometres across on Earth for the tell tale signs of this squeezing. Although great things are expcted, these experiments have so far thrown up precisely nothing.

But there’s another way. Gravitational waves should also stretch and squeeze pulsars as they pass by, subtly changing the radio pulses they produce. So by monitoring an array of pulsars throughout the galaxy, astronomers should be able to see the effects of nanohertz to microhertz gravitational waves passing by. The array of pulsars should effectively shimmer as the waves wash over it, like a grid of buoys bobbing on the ocean.

So the plan is to keep a beedy eye on an array of carefully chosen pulsars. It’s called the North American Nanohertz Observatory for Gravitational Waves or NANOGrav and it’s part of an international effort to spot gravitational waves in this way.

Of course, these kinds of observations are hard to make. First, astronomers need well-characterised millisecond pulsars to observe. They’re not easy to find and there appears to be a particular dearth of them in the northern hemisphere. And measuring them with the required accuracy isn’t easy either, say Fredrick Jenet at the University of Texas, Brownsville, and a few buddies.

But there’s hope on the horizon. These guys say the next generation of radio telescope arrays such as the Allen Telescope Array in California and the Square Kilometer Array in Australia or South Africa, should be capable of making the required measurements. And the scientific potential of the data is huge.

The team says the observations should help them understand how galaxies and supermassive black holes evolve together, shed light on the physics of the early universe such as inflation as well as probing the nature of space-time, perhaps revealing quantum gravity corrections to classical gravity. It may even throw up some new sources of gravitational waves.

Of course, many of those things are also the goals of the Earth-based gravitational wave observatories, which have cost hundreds of millions of dollars to build and more to maintain and upgrade. By contrast, the NANOGrav team estimates the cost of its project over ten years to be a mere $66 million.

It expects to be up and running by 2020 and at that price looks remarkably good value.

Ref: arxiv.org/abs/0909.1058: The North American Nanohertz Observatory for Gravitational Waves

Deep Dive

Uncategorized

Five poems about the mind

DREAM VENDING MACHINE I feed it coins and watch the spring coil back,the clunk of a vacuum-packed, foil-wrappeddream dropping into the tray. It dispenses all kinds of dreams—bad dreams, good dreams,short nightmares to stave off worse ones, recurring dreams with a teacake marshmallow center.Hardboiled caramel dreams to tuck in your cheek,a bag of orange dreams…

Work reinvented: Tech will drive the office evolution

As organizations navigate a new world of hybrid work, tech innovation will be crucial for employee connection and collaboration.

lucid dreaming concept
lucid dreaming concept

I taught myself to lucid dream. You can too.

We still don’t know much about the experience of being aware that you’re dreaming—but a few researchers think it could help us find out more about how the brain works.

panpsychism concept
panpsychism concept

Is everything in the world a little bit conscious?

The idea that consciousness is widespread is attractive to many for intellectual and, perhaps, also emotional
reasons. But can it be tested? Surprisingly, perhaps it can.

Stay connected

Illustration by Rose WongIllustration by Rose Wong

Get the latest updates from
MIT Technology Review

Discover special offers, top stories, upcoming events, and more.

Thank you for submitting your email!

Explore more newsletters

It looks like something went wrong.

We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at customer-service@technologyreview.com with a list of newsletters you’d like to receive.