SearchLites - Vol 14 No 4

Magazine Overview

SearchLites, Volume 14, Number 4, Autumn 2008, is the quarterly newsletter of The SETI League, Inc. This issue features articles on the intersection of SETI with international organizations, scientific inquiries into cosmic phenomena, and updates on radio astronomy activities and funding.

UNESCO and SETI

Authored by Kathryn Denning and Elisabeth Piotelat, this article explores how the Search for Extraterrestrial Intelligence (SETI) fits within the mission and worldview of UNESCO (United Nations Educational, Scientific, and Cultural Organisation). The authors argue that SETI aligns well with UNESCO's purpose of building peace through education, science, culture, and communication. Its international scope, encouragement of big-picture thinking, need for cross-cultural understanding, and role in debating Earth's future and 'who speaks for Earth?' all resonate with UNESCO's mandate. The article highlights how SETI@home, a distributed computing experiment, fostered a sense of community and scientific inquiry among its users, indirectly contributing to humanitarian efforts like fighting malaria. The authors conclude that SETI is a logical extension of the mission of organizations like UNESCO and the United Nations, which were founded to foster international understanding.

Stonehenge and SETI

In this guest editorial, Dennis Price posits that Stonehenge, a prehistoric monument, can be viewed as an early SETI structure. He argues that the builders, possessing significant intelligence, were fascinated by the night sky and engaged in a 'prolonged search for extra-terrestrial intelligence,' whether defined as information gleaned from observation or sentient existence beyond Earth. Price draws parallels between the ancient sky-watchers and modern SETI practitioners, noting that both sought to understand the cosmos and potential intelligent life within it. He recounts seeking a second opinion from Christopher J Corbally of the Vatican Observatory, who agreed that the builders likely pondered life and intelligent life elsewhere, even if their scientific tools were different.

Ask Dr. SETI®

This section addresses several reader questions:

Black Holes and FTL

A reader from Portland asks if crossing a black hole's event horizon constitutes traveling faster than light and if a gravity-assist maneuver could achieve such speeds. The Doctor responds that while spacetime is warped by a black hole's gravity, the 'c' limit is preserved from external viewpoints. Inside the event horizon, exceeding 'c' would mean ceasing to exist, making practical harnessing difficult.

Shouldn't Earth Temperature Dominate?

David from Alaska inquires why a receiver pointed away from Earth doesn't register the reflector's temperature instead of the low temperature of space. The Doctor explains that a parabolic reflector acts as a thermal mirror, reflecting the sky's temperature. While the reflector and Earth contribute noise, sky temperature usually dominates unless the system design is flawed.

NASA Deep Space Network SETI Beacons

Ed from Alaska asks about using 8.4 GHz (NASA Deep Space Network frequency) for SETI. The Doctor acknowledges X-band as a valid spectrum for monitoring, but doubts that signals from our spacecraft, designed for low power and directed Earthward, could be detected by extraterrestrials over interstellar distances. However, uplink signals from Earth to spacecraft, transmitted by powerful NASA Deep Space Network transmitters, might be detectable.

Dark Matter Frequencies

Grant from Australia questions the logic of searching for SETI signals on the Hydrogen line (1420MHz) when dark matter constitutes a much larger portion of the universe. The Doctor explains that while the logic is sound, the nature of dark matter is unknown—it's invisible, and its emission frequencies, if any, are undiscovered. In contrast, baryonic matter like Hydrogen emits detectable electromagnetic signposts.

RF Absorption of Polystyrene Foam

Marcus from Canada asks about the RF absorption of polystyrene foam at L-band frequencies. The Doctor suggests a simple microwave test: if the foam warms up, it absorbs RF. Marcus reports that standard pink styrofoam showed minimal warming, suggesting it would be suitable for insulation at 21cm.

Tree Attenuation

Greg from Sweden asks if trees significantly attenuate L/S-band signals. The Doctor explains three mechanisms: water attenuation (due to water molecules resonating at microwave frequencies), thermal radiation from the trees themselves, and physical resonances where foliage can act like a dipole antenna. He advises clearing trees if possible or hoping for dry conditions, cold winters, and non-resonant leaves.

Radio Astronomers Offer Membership Incentive

This section announces a membership incentive offered by the Society of Amateur Radio Astronomers (SARA), a SETI League affiliate. For one year, SETI League members can join SARA and receive full membership benefits through June 2010, plus a free copy of the SARA Journal CD. This reciprocal offer mirrors a previous deal where SARA members joining The SETI League received benefits.

Proceedings of the 2008 Conference of the Society of Amateur Radio Astronomers

A listing of the table of contents for the 2008 SARA Conference Proceedings is provided, detailing various presentations on radio astronomy, cosmology, and SETI-related topics. The proceedings are available for purchase.

Arecibo Observatory Funding

By G. Warren Coleman, WD4NIT, this article discusses the significant funding reductions facing the Arecibo Radio-Radar Observatory in Puerto Rico. Originally funded by the Department of Defense for ionospheric research, Arecibo evolved into a general-purpose radio-radar observatory with notable achievements, such as determining Mercury's rotation rate and confirming Crab Nebula pulses. The National Science Foundation assumed control in 1969. The author urges readers to contact Congress to maintain Arecibo's funding, emphasizing its critical role in planetary surveillance and NEO detection, while downplaying its SETI work due to potential negative congressional attitudes.

The SETI League Thanks

A brief acknowledgment of an anonymous donation in memory of Gary Schaefer.

Event Horizon

A list of upcoming conferences and meetings related to SETI and astronomy is provided, with dates and locations, inviting members to attend and share information.

Annual Renewal

This section serves as a renewal notice for SETI League memberships, reminding members to check their expiration dates and renew. It also lists various membership categories and premiums available for purchase, including proceedings, books, and merchandise.

Recurring Themes and Editorial Stance

The recurring themes in this issue include the international and collaborative nature of SETI, its potential to foster understanding and address ethical issues, and its connection to broader scientific endeavors like radio astronomy and space exploration. The newsletter consistently promotes the SETI League's mission and encourages member participation and support. The editorial stance is one of advocacy for SETI research, scientific inquiry, and international cooperation in the pursuit of knowledge about extraterrestrial intelligence and the universe.