Tag Archives: National Radio Astronomy Obeservatory

SDRs processing Fast Radio Bursts from distant universe

The Green Bank Telescope (Source: NRAO)

Many thanks to SWLing Post contributor, Ed, who shares a link to the following article at Breakthrough Initiatives:

Green Bank Telescope observations of a dwarf galaxy three billion light years away reveal 15 bursts of radio emission. This is the first time bursts from this source have been seen at these frequencies.

San Francisco – August 29, 2017 – Breakthrough Listen – the initiative to find signs of intelligent life in the universe – has detected 15 fast radio bursts emanating from the mysterious “repeater” FRB 121102. Fast radio bursts, or FRBs, are brief, bright pulses of radio emission from distant galaxies. First detected with the Parkes Telescope in Australia, FRBs have now been seen by several radio telescopes around the world. FRB 121102 was discovered in 2012, on November 2nd (hence its name). In 2015, it was the first FRB seen to repeat, ruling out theories of the bursts’ origins that involved the catastrophic destruction of the progenitor (at least in this particular instance). And in 2016, the repeater was the first FRB to have its location pinpointed with sufficient precision to allow its host galaxy to be identified. It resides in a dwarf galaxy about 3 billion light years away from Earth.

Attempts to understand the mechanism that generates FRBs have made this galaxy a target of ongoing monitoring campaigns by instruments across the globe. Possible explanations for FRBs range from outbursts from rotating neutron stars with extremely strong magnetic fields, to more speculative ideas that they are directed energy sources used by extraterrestrial civilizations to power spacecraft.

Breakthrough Listen is a global astronomical initiative launched in 2015 by Internet investor and philanthropist Yuri Milner and cosmologist Stephen Hawking. As part of their program to observe nearby stars and galaxies for signatures of extraterrestrial technology, the Listen science team at UC Berkeley added FRB 121102 to their list of targets. In the early hours of Saturday, August 26, UC Berkeley Postdoctoral Researcher Dr. Vishal Gajjar observed the location of FRB 121102 using the Breakthrough Listen backend instrument at the Green Bank Telescope in West Virginia. The instrument accumulated 400 TB of data on the object over a five hour observation, observing the entire 4 to 8 GHz frequency band.[…]

Analysis by Dr. Gajjar and the Listen team revealed 15 new pulses from FRB 121102. As well as confirming that the source is in a newly active state, the high resolution of the data obtained by the Listen instrument will allow measurement of the properties of these mysterious bursts at a higher precision than ever possible before.

The observations also show for the first time that FRBs emit at higher frequencies (with the brightest emission occurring at around 7 GHz) than previously observed. The extraordinary capabilities of the Listen backend, which is able to record several gigahertz of bandwidth at a time, split into billions of individual channels, enable a new view of the frequency spectrum of FRBs, and should shed additional light on the processes giving rise to FRB emission.
When the recently-detected pulses left their host galaxy our entire Solar System was just 2 billion years old. […]

The new results are reported as an Astronomer’s Telegram at www.astronomerstelegram.org/?read=10675 and will be described in further detail in an upcoming scientific journal article.

Breakthrough Listen is a scientific program in search for evidence of technological life in the Universe. It aims to survey one million nearby stars, the entire galactic plane and 100 nearby galaxies at a wide range of radio and optical bands.[…]

The linked animation shows 14 of the 15 detected bursts in succession, illustrating their dispersed spectrum and extreme variability. Capturing this diverse set of bursts was made possible by the broad bandwidth that can be processed by the Breakthrough Listen backend at the Green Bank Telescope:

https://storage.googleapis.com/frb121102/FRB121102_Cband_GB.gif

Click here to read the full article at Breakthrough Initiatives.

Will Green Bank soon become a little less radio quiet?

GreenBankTelescope(Source: BBC News via Richard Langley)

Disturbing the peace: Can America’s quietest town be saved?

There’s a town in West Virginia where there are tight restrictions on mobile signal, wifi and other parts of what most of us know as simply: modern life. It means Green Bank is a place unlike anywhere else in the world. But that could be set to change.

“Do you ever sit awake at night and wonder, what if?” I asked.

Mike Holstine’s eyes twinkled like the stars he had spent his life’s work observing.

“The universe is so huge,” he began.

“On the off chance we do get that hugely lucky signal, when we look in the right place, at the right frequency. When we get that… can you imagine what that’s going to do to humankind?”

Holstine is business manager at the Green Bank Observatory, the centrepiece of which is the colossal Green Bank Telescope. On a foggy Tuesday morning, I’m standing in the middle of it, looking up, feeling small.

Though the GBT has many research tasks, the one everyone talks about is the search for extra-terrestrial intelligence. The GBT listens out for signs of communication or activity by species that are not from Earth.

[…]Green Bank sits at the heart of the National Radio Quiet Zone, a 13,000 square mile (33,669 sq km) area where certain types of transmissions are restricted so as not to create interference to the variety of instruments set up in the hills – as well as the Green Bank Observatory, there is also Sugar Grove, a US intelligence agency outpost.

For those in the immediate vicinity of the GBT, the rules are more strict. Your mobile phone is useless here, you will not get a TV signal and you can’t have strong wi-fi? -?though they admit this is a losing battle. Modern life is winning, gradually. And newer wi-fi standards do not interfere with the same frequencies as before.[…]

Read the full article on the BBC News website.

Additionally, if you have access to the BBC iPlayer, click here to watch the Click episode featuring Green Bank.

National Radio Quiet Zone featured in BBC Radio 4 series

GreenBankTelescope

Many thanks to SWLing Post reader, David Freeborough, who shares this brilliant, in-depth radio documentary featured on the BBC News and BBC Radio 4.

This BBC News Magazine article introduces the documentary:

“Anyone driving west from Washington DC towards the Allegheny Mountains will arrive before long in a vast area without mobile phone signals. This is the National Radio Quiet Zone – 13,000 square miles (34,000 sq km) of radio silence. What is it for and how long will it survive?

As we drive into the Allegheny Mountains the car radio fades to static. I glance at my mobile phone but the signal has disappeared.

Ahead of us a dazzling white saucer looms above the wooded terrain of West Virginia, getting bigger and bigger with every mile. It’s the planet’s largest land-based movable object – the Robert C Byrd Green Bank Telescope (GBT) – 2.3 acres in surface area, and taller than the Statue of Liberty.

But it needs electrical peace and quiet to do its job.”

[Continue reading…]

The story continues on the BBC News site, but I would encourage you to listen to the five part radio documentary series on BBC Radio 4 first. Green Bank, WV, is certainly one part of the planet where a shortwave radio listener would be quite happy: residents have virtually no radio interference or obnoxious electrical noises that plague the rest of the modern world.

telescopes-1911The radio documentary can be streamed on the Radio 4 website.  I’ve included links to each episode below. As far as I can tell, there are no expiration dates on the Radio 4 streams:

My wife and I have camped near the NROA site in Green Bank–it’s a beautiful part of the world. I’m certainly long overdue to return!

Again, David, many thanks for sharing this!