Tag Archives: Radio Astronomy

Tom explores the depths of radio astronomy

26 meter telescope at the Pisgah Astronomical Research Institute.

Many thanks to SWLing Post contributor, Tom L, who writes:

I have been curiously surveying uses of radio in different areas of industry and Astronomy came up as a hot topic the last couple of years according to recent Google searches. Radio was a giant popular commercial success in the 1930’s and 1940’s. But Radio Astronomy was still in its infancy with military radar. A Bell Labs engineer (Karl Jansky) accidentally discovered signals coming from an unknown source. He and his mentor figured out that it was coming from the center of the Milky Way.

https://en.wikipedia.org/wiki/Radio_astronomy

Fast forward to today and it looks nothing like the early days. Computer control and very large arrays have made it possible to boost the wide-field resolution massively. We are now able to see molecules in space outside our solar system and filaments connecting star nurseries. Here are just a few recent articles that hint at major news coming from this field of study. If you have a science student interested and has the talent for Astronomy, Radio Astronomy promises to be on a variety of cutting edges of discoveries over the next few decades from local Space Weather, biological search, and how stars form.

Radio telescopes are essential to discovering “Galaxy Ecosystems”: Click here to download PDF.

Enjoy!

Thanks, Tom!  I’ve been fascinated with radio astronomy since my undergraduate years in the early 1990s. I’m now a volunteer at the Pisgah Astronomical Research Institute (PARI) and have learned so much through their research. If you ever have the time, I would encourage you to visit PARI or one of the NROA sites like Green Bank or the Very Large Array.  Well worth the detour! Thanks for sharing those articles!

Listening to Oumuamua via the Green Bank Telescope

Many thanks to SWLing Post contributor, Ferruccio Manfieri, who writes:

I bother you to mention this uncommon radio listening project i’ve just found via The Guardian:

Green Bank telescope in West Virginia will listen for radio signals from ‘Oumuamua, an object from another solar system

Astronomers are to use one of the world’s largest telescopes to check a mysterious object that is speeding through the solar system for signs of alien technology.

The Green Bank telescope in West Virginia will listen for radio signals being broadcast from a cigar-shaped body which was first spotted in the solar system in October. The body arrived from interstellar space and reached a peak speed of 196,000 mph as it swept past the sun.

Scientists on the Breakthrough Listen project, which searches for evidence of alien civilisations, said the Green Bank telescope would monitor the object, named ‘Oumuamua, from Wednesday. The first phase of observations is expected to last 10 hours and will tune in to four different radio transmission bands.

“Most likely it is of natural origin, but because it is so peculiar, we would like to check if it has any sign of artificial origin, such as radio emissions,” said Avi Loeb, professor of astronomy at Harvard University and an adviser to the Breakthrough Listen project. “If we do detect a signal that appears artificial in origin, we’ll know immediately.”

The linked article says that “(…)Scientists on the Breakthrough Listen project, which searches for evidence of alien civilisations, said the Green Bank telescope would monitor the object, named ‘Oumuamua, from Wednesday. The first phase of observations is expected to last 10 hours and will tune in to four different radio transmission bands.”

From the website of the project (http://breakthroughinitiatives.org/initiative/1):

Breakthrough Listen is the largest ever scientific research program aimed at finding evidence of civilizations beyond Earth. The scope and power of the search are on an unprecedented scale:

The program includes a survey of the 1,000,000 closest stars to Earth. It scans the center of our galaxy and the entire galactic plane. Beyond the Milky Way, it listens for messages from the 100 closest galaxies to ours.

The instruments used are among the world’s most powerful. They are 50 times more sensitive than existing telescopes dedicated to the search for intelligence.
The radio surveys cover 10 times more of the sky than previous programs. They also cover at least 5 times more of the radio spectrum – and do it 100 times faster. They are sensitive enough to hear a common aircraft radar transmitting to us from any of the 1000 nearest stars.

In particular:

“Listen’s observation campaign will begin on Wednesday, December 13 at 3:00 pm ET. Using the Robert C. Byrd Green Bank Telescope, it will continue to observe ‘Oumuamua across four radio bands, from 1 to 12 GHz. Its first phase of observations will last a total of 10 hours, divided into four “epochs” based on the object’s period of rotation.”

I know it’s out of our common shortwave range and scope of interest, but as a radio listening enthusiast I’m fascinated by this visionary scientific enterprise.

Thank you, Ferruccio, for sharing this.  Being a fan of radio astronomy, SETI, and weak signal DXing, of course I find this fascinating!  Thanks for sharing!

Hurricane Damages Arecibo Radio Telescope

Arecibo Observatory

(Source: National Geographic via Eric WD8RIF)

Hurricane Damages Giant Radio Telescope—Why It Matters” at National Geographic, written by the daughter of Frank Drake, pioneer SETI investigator:

Scientists and ham radio operators have confirmed that the Arecibo Observatory in Puerto Rico—arguably the world’s most iconic radio telescope, which has a dish stretching a thousand feet across—has come through Hurricane Maria mostly intact, but with some significant damage.

More importantly, the observatory’s staff sheltering on-site are safe, and the facility is in good enough condition to potentially serve as a local center for the U.S. Federal Emergency Management Agency, or FEMA, reports Arecibo deputy director Joan Schmelz.

Because of its deep water well and generator, the observatory has been a place for those in nearby towns to gather, shower, and cook after past hurricanes. It also has an on-site helicopter landing pad, so making sure the facility is safe in general is not just of scientific importance, but is also relevant for local relief efforts.

News about the facility has been primarily coming from Arecibo telescope operator Ángel Vazquez, who managed to get to the site and start communicating via short-wave radio in the early evening of September 21.

According to initial reports, the hurricane damaged a smaller, 12-meter dish and it caused substantial damage to the main dish, including about 20 surface tiles that were knocked loose.

Also because of the storm, a 96-foot line feed antenna—which helps focus, receive, and transmit radio waves—broke in half and fell about 500 feet into the huge dish below, puncturing it in several places, says Pennsylvania State University’s Jim Breakall, who talked with Vazquez.[…]

Click here to read the full article.

Five reasons why FRBs aren’t being broadcast by ET

Many thanks to SWLing Post contributor, Ed, who shares an update to his previous post regarding Fast Radio Bursts. Ed writes:

Here’s a followup article explaining, “Five Reasons Why The Signals From Stephen Hawking’s Breakthrough Initiative Aren’t Aliens”.

It compares the power of these Fast Radio Bursts (FRB’s) with that of the mediumwave array in Roumoules, France (the most powerful radio broadcast facility in the world) which is reportedly nineteen orders of magnitude *weaker* than these FRB signals. Wow!

https://www.forbes.com/sites/startswithabang/2017/09/04/five-reasons-why-the-signals-from-stephen-hawkings-breakthrough-initiative-arent-aliens/#7544e2c017a7

It also mentions the novel Canadian CHIME radio telescope under construction [above], which will have the most gain of any in the world.

http://chime.phas.ubc.ca/

Thanks, Ed! Yeah, while I would certainly love to hear that the SETI program has identified broadcasts from other intelligent beings, the likelihood is that any candidate signal(s) are explainable in many other ways. Still, what’s so great about the SETI program is they doggedly pursue the search, pour over the data, scrutinize the results, draw conclusions then continue the search.

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.