SETI@home

It is hosted by the Space Sciences Laboratory at the University of California, Berkeley, and is one of many activities undertaken as part of the worldwide SETI effort.

However, the team left open the possibility of eventually resuming volunteer computing using data from other radio telescopes, such as MeerKAT and FAST.

The current BOINC environment, a development of the original SETI@home, is providing support for many computationally intensive projects in a wide range of disciplines.

The data is then parsed into small chunks in frequency and time, and analyzed, using software, to search for any signals—that is, variations which cannot be ascribed to noise, and hence contain information.

Thus what appears a difficult problem in data analysis is reduced to a reasonable one by aid from a large, Internet-based community of borrowed computer resources.

The potential "signal" is thus processed in many ways (although not testing all detection methods nor scenarios) to ensure the highest likelihood of distinguishing it from the scintillating noise already present in all directions of outer space.

More technically, it involves a lot of digital signal processing, mostly discrete Fourier transforms at various chirp rates and durations.

Astronomer Seth Shostak stated in 2004 that he expects to get a conclusive signal and proof of alien contact between 2020 and 2025, based on the Drake equation.

[19] This implies that a prolonged effort may benefit SETI@home, despite its (present) twenty-year run without success in ETI detection.

Anybody with an at least intermittently Internet-connected computer was able to participate in SETI@home by running a free program that downloaded and analyzed radio telescope data.

[24] The SETI@home volunteer computing software ran either as a screensaver or continuously while a user worked, making use of processor time that would otherwise be unused.

Other plans include a Multi-Beam Data Recorder, a Near Time Persistency Checker and Astropulse (an application that uses coherent dedispersion to search for pulsed signals).

[30] Astropulse will team with the original SETI@home to detect other sources, such as rapidly rotating pulsars, exploding primordial black holes, or as-yet unknown astrophysical phenomena.

On March 31, 2020, UC Berkeley stopped sending out new data for SETI@Home clients to process, ending the effort for the time being.

To combat cheats, the SETI@home system sends every work unit to multiple computers, a value known as "initial replication" (currently 2).

If, due to computation errors or cheating by submitting false data, not enough results agree, more identical work units are sent out until the minimum quorum can be reached.

Other users collect large quantities of equipment together at home to create "SETI farms", which typically consist of a number of computers consisting of only a motherboard, CPU, RAM and power supply that are arranged on shelves as diskless workstations running either Linux or old versions of Microsoft Windows "headless" (without a monitor).

[35] Until 2020, SETI@home procured its data from the Arecibo Observatory facility that was operated by the National Astronomy and Ionosphere Center and administered by SRI International.

In one documented case, an individual was fired for explicitly importing and using the SETI@home software on computers used for the U.S. state of Ohio.

[38] In another incident a school IT director resigned after his installation allegedly cost his school district $1 million in removal costs; however, other reasons for this firing included lack of communication with his superiors, not installing firewall software and alleged theft of computer equipment,[39] leading a ZDNet editor to comment that "the volunteer computing nonsense was simply the best and most obvious excuse the district had to terminate his contract with cause".

[40] As of 16 October 2005[update], approximately one-third of the processing for the non-BOINC version of the software was performed on work or school based machines.

For example, in 2012, Piotr Luszczek (a former doctoral student of Jack Dongarra) presented results showing that an iPad 2 matched the historical performance of a Cray-2 (the fastest computer in the world in 1985) on an embedded LINPACK benchmark.

The BOINC Manager working on the SETI@home project (v 7.6.22)
Screenshot of SETI@home Classic Screensaver (v3.07)