Monday, April 29, 2013

Needles in the Cosmic Haystack: Reflections on Dr. Jill Tarter's Lecture on Cosmic Boundaries

On Monday, April 29, 2013, Dr. Jill Tarter, from the SETI Institute, provided an insightful overview of "specific searches for technological civilizations that might occupy one or more of the recently discovered exoplanets in our galactic neighborhood." Tarter is credited as Carl Sagan’s inspiration for the novel and subsequent film Contact. Read more here.

Event producers noted, "The Center for SETI Research collects an outstanding 3 petabytes of raw data from the Allen Telescope Array each day and sifts through the 9-dimensional 'Cosmic Haystack' to find some 'needle' of a signal. For the last 35 years, Dr. Tarter and the SETI Institute have been using telescopes to systematically search for evidence of other technological civilizations in the Milky Way Galaxy." SETI engages in an archeology of the future. 
SETI drives the search for intelligent life; this is the noble work of astrobiologists. 

No mean undertaking. 

A recent major breakthrough is the Allen Telescope Array (ATA) built from scratch for SETI radio astronomy. On the ATA, SETI reports:
"The Allen Telescope Array (ATA) is a "Large Number of Small Dishes" (LNSD) array designed to be highly effective for “commensal” (simultaneous) surveys of conventional radio astronomy projects and SETI (search for extraterrestrial intelligence) observations at centimeter wavelengths."
"The idea for the ATA emerged in a series of workshops convened by the SETI Institute in 1997 to define the path for future development of technology and search strategies for SETI. The advance of computer and communications technology made it clear that LNSD arrays were more efficient and less expensive than traditional large antennas. The final report of the workshop, “SETI 2020,” recommended the construction of the One Hectare Telescope. (1HT) (A hectare is an area equivalent to a square 100 meters on a side.)The SETI Institute sought private funds for the 1HT and in 2001 Paul Allen (co-founder of Microsoft) agreed to fund the technology development and first phase of construction (42 antennas). In October 2007 the array began commissioning tests and initial observations.The array is now being used for radio astronomy observations of our galaxy and other galaxies, gamma ray bursts and transient radio sources, and SETI."
There are a number of current challenges with collecting and interpreting "big space data," technical challenges to technolgical progress, and challenges in communicating the SETI mission with larger audiences. This talk was particularly timely given the current state of space-exploration and given the recent discovery of a new planetary system.

Humans have been on a journey to explore the meaning of life and the nature of life since the beginning of human experience. Enter astronomy. Are we a lonely planet floating through the multiverse alone? Unlikely. 

In some ways, we are in the boondocks of the Milky Way. 400 billion stars in the grand spiral galaxies, which is 1 of 100 billion galaxies. We have only charted 4% of the mass density of the universe: the rest: dark matter/energy. The unknown. So...there is some work to do yet. 

"We are on a fragile island of life in a universe full of possibilities."
artist rendition: Kepler Spacecraft
Critical Question: Where is the second planet or solar system that is full of life? Until 1995, we didn't know about the existence of planets orbiting other stars - exoplanets. Enter NASA's Kepler spacecraft that searches 100 square degrees, 1-400th of the total sky. The spacecraft uses a 93 mega-pixel camera to stare at 150,000 stars selected by Kepler scientists. 
"Kepler is part of NASA's Discovery Program of relatively low-cost, focused primary science missions. The telescope's construction and initial operation were managed by NASA's Jet Propulsion Laboratory, with Ball Aerospace responsible for developing the Kepler flight system. The Ames Research Center is responsible for the ground system development, mission operations since December 2009, and science data analysis. The initial planned lifetime was 3.5 years, but in 2012 this was extended to 2016, partly due to difficulties in processing and analyzing the huge volume of data collected by the spacecraft." (Wiki, 2013)
Kepler by the Numbers
  • 122 exoplanets confirmed
  • 2740 candidate exoplanets
  • 58 in HZ (183-303k) - the temp on the these planets might have liquid water.
We are close to finding Earth 2.0., and we might find this planet in a habitable zone that orbits as star similar to the sun.
"Smaller planets are more easily found around smaller stars." 
Signal Detection Critical Questions
  • How long do these technologies last? 
  • How do they activate and turn-off?
  • Are we close enough in time-space to find these signals?
The search for intelligent life began in earnest in the 1950s with radio signals and the re- purposing of satellite dishes used in WWII for interstellar signal searching. Fast-forward to today, can we find life that uses technology to modify its environments, and can we find those life-markers using our technology? Today, SETI uses frequency compression, signals so narrow that only technology can create or recognize such signals. The thought is to detect technologies emanating from a planet analogous to Earth. The problem is that those signals come from a long way away and long time away. As Tarter phrased it, "Here is the tyranny of light speed." 

We are in our technological infancy. Young technology in an old universe. We need to find long-lived technology. If we find said technology, it might mean we ourselves could also create long-standing technologies. Tarter argued that technology will have to live for 100,000 years for us to currently detect intelligent signals. A short period of time in cosmic speak, many times many ages in human time.

SETI is looking for two kinds of deliberate signals:

1. Things that look almost "natural"

  • One such example would be a pulsar. There are a number of pulsar surveys of the sky. There could be a signal of life. 
2. Engineered - purposeful signals not created in nature as we know it
  • single frequency on dial 
  • single nanosecond in time
Finding a needle (signal) in the cosmic haystack involves a 9-dimensional-space to search. 
3 - space
1 - time
2 - polarizations
1 - frequency
1 - modulation scheme
1 - sensitivity
9 dimensions

The exponential growth of technology is now allowing astrobiologist to meet the demands of these dimensions. New tech includes sky surveys using OSETI (commensal on bigger glass).
One exciting area of growth is the mixing of SETI technology with machine learning to teach machines to better recognize signals. Smarter machines will mean greater likelihood to locate intelligent signals.

What does the future-now hold? One example is the James Webb Space Telescope (JWST) that will search for bio-signatures and the byproducts of biotechnology. NASA reports:
Webb diagram
"The James Webb Space Telescope (sometimes called JWST) is a large, infrared-optimized space telescope. The project is working to a 2018 launch date. Webb will find the first galaxies that formed in the early Universe, connecting the Big Bang to our own Milky Way Galaxy. Webb will peer through dusty clouds to see stars forming planetary systems, connecting the Milky Way to our own Solar System. Webb's instruments will be designed to work primarily in the infrared range of the electromagnetic spectrum, with some capability in the visible range. Webb will have a large mirror, 6.5 meters (21.3 feet) in diameter and asunshield the size of a tennis court. Both the mirror and sunshade won't fit onto a rocket fully open, so both will fold up and open once Webb is in outer space. Webb will reside in an orbit about 1.5 million km (1 million miles) from the Earth."

Tarter challenged the audience to seek out anomalies in the data. We can take this advice and enact it across disciplines. Seek out the unknown, the margins, the outliers, the data outside the mean to help better understand our research, business questions, and new technologies. 

The critical point here is that all humans belong to one tribe - earthlings - this is the larger frame that SETI asks us to consider. SETI research might help to bridge our sociocultural differences, and provide an opportunity, through global scientific practice, to meet the challenges that we face as humans. SETI is good practice for global cooperation. These are problems that don't recognize (but are influenced by) national borders: global warming, water access, food shortages, and technological growth. Transnational cooperation is the call from SETI. Heed it.

Interested in learning more? Me too. Check out SETI@home. Why not use your home computer in the search for life? Pitch in.

This event was sponsored by PayPal's TechXploration Meet-Up in partnership with the SETI Institute. Find more about this growing meet-up here.

ATA  - Jill Tarter

(Video source: SETI Institute)

Kepler Mission: Past, Present, and Future - Bill Borucki (SETI Talks)

(Video source: SETI Institute)

Image source: By SESI-BOINC (SETI OFFICAL SITE) [CC0], via Wikimedia Commons

Image source: By Jcolbyk at en.wikipedia [GFDL ( or CC-BY-SA-3.0 (], from Wikimedia Commons

Image source: By NASA [Public domain], via Wikimedia Commons

Image source: Tropenmuseum of the Royal Tropical Institute (KIT) [CC-BY-SA-3.0 (], via Wikimedia Commons

Image source: By NASA ( [Public domain], via Wikimedia Commons

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