Allen Telescope Array

ATA aerial

Allen Telescope Array Gallery

These images of the Allen Telescope Array can be used for free without requesting permission.  Credit should be “Seth Shostak/SETI Institute”.    For higher-resolution versions, please inquire at  

Is this mysterious space rock actually an alien spaceship?

It’s in the news because people want to know if it’s a rock or a rocket. The “it” in question is a weirdly oblong asteroid that goes by the barely pronounceable moniker 'Oumuamua. It was first seen about a month ago by Pan-STARRS, a collection of telescopes perched high above the handsome beaches of the Hawaiian island of Maui. Like a motorcycle on the freeway, it was observed by astronomers…
Green Bank Telescope

FRB 121102: Radio Calling Cards from a Distant Civilization?

It’s a signal that begs for superlatives.  The Breakthrough Listen project recently announced the detection of 15 pulses of radio energy from an object known to the astronomy community as FRB 121102. There have been roughly 30 fast radio bursters (FRBs) detected so far, but FRB 121102 is the only one that has erupted more than once.  Repetition is a boon for those trying to unravel the nature of…
Tabby's Star

What’s Up with Tabby’s Star?

By now you have surely heard that Boyajian’s star, aka Tabby’s star, aka KIC8462852, is going through another weird dimming phase. We do not have a satisfactory explanation for why Boyajian’s star sometimes dims by 20%, and many astronomers are monitoring the star with optical and infrared telescopes, hoping to learn more about this strange behavior. Likewise, the SETI Institute has shifted into…
Galactic Center

SETI on the ATA: Galactic Center Survey

The region near the center of our galaxy contains the highest concentration of stars in the sky, yet has only been searched for ETI signals at a few “magic” frequencies. We will search a large area near the galactic center over the entire “waterhole” frequency range, from 1420 to 1720 MHz. This frequency range is defined by the spectral lines for the dissociation products of water, the sine qua…
Ross 128

Signals from A Nearby Star System?

UPDATE July 24, 2017   Encouraged by the strange signals recorded at the Arecibo radio telescope, the Allen Telescope Array was used to try and confirm same, as noted. The ATA observed Ross128 for about 16 hours over three days, and while there was human-generated interference, there was no evidence for a signal originating from the star system. The Green Bank Telescope, part of the Breakthrough…

Rosetta's Target: Comet 67P/Churyumov-Gerasimenko

As Rosetta crashed into comet 67p, it dipped below the horizon for the last time as seen from the Allen Telescope Array (ATA) at 05:55pm Pacific time, September 29, 2016. I've used its signal a lot over the years to test our receiving system. Now I'll have to find another spacecraft! For 12+ hours a day we use the ATA to search for radio transmissions from distant stars and planets. But it was a…
Allen Telescope Array

Meteor passes near to Allen Telescope Array

SETI Institute astronomer Peter Jenniskens notes that a very bright meteor, a so-called fireball, was seen in the vicinity of the Allen Telescope Array on Thursday, September 15 at about 7:48 pm local time.  Image screenshot taken from the American Meteor Society website. You can read the report here:  
OSIRIS-REx graph

OSIRIS-REx says hello to the ATA!

The Allen Telescope Array (ATA) uses 42 radio dishes to search for radio transmissions from ET. How do we know the system is working? To answer that question, we point the dishes in the direction of a spacecraft we know is transmitting radio signals back to Earth. If our software detects a radio transmission at the exact frequency as the spacecraft's transmission, we know things are working as…

A SETI Signal?

A star system 94 light-years away is in the spotlight as a possible candidate for intelligent inhabitants, thanks to the discovery of a radio signal by a group of Russian astronomers. The RATAN-600 radio telescope, credit: HD 164595, a solar system a few billion years older than the Sun but centered on a star of comparable size and brightness, is the purported source of a signal…