SETI@home

Preguntas corrientes sobre SETI@home - FAQ
- En proceso de traducción -


Perdonen las molestias

Categorias FAQ

  1. Empezando
  2. Ejecutando SETI@home
  3. Prestaciones y crédito
  4. El proyecto
  5. Windows
  6. Macintosh
  7. UNIX
  8. Plataforams
  9. Distribución de datos SETI@home
  10. La ciencia en SETI@home
  11. SETI en general

Si no puede encontrar a su pregunta, por favor añádala.


Empezando

  1. Que necesito para participar en SETI@home?
  2. Necesito saber algo de ciencia o extraterrestre para usar SETI@home?
  3. Cuanto tiempo se tarda en descargar el salvapantallas?
  4. Pago por cada hora que me conecto a Internet. Cuanto tiempo necesito conectarme a SETI@home?
  5. Que hay de la seguridad?
  6. Es muy complejo el software? Los usuarios tienen que estar conectando y desconectando o enviando los resultados? Tiene que estar el computador conectado a Internet todo el tiempo?
  7. Descargué el software pero mi computador no sabe que hacer con un fichero .exe/.sit/.hqx/.tar - ¿ Que hago ?

Ejecutando SETI@home

  1. Los gráficos no se mueven. ¿ Se quemará mi pantalla ?
  2. ¿Si apago el computador con SETI@home funcionando se pierden los datos?
  3. ¿Puedo hacerlo funcionar en todos los computadores que quiera con el mismo usuario SETI@home?
  4. ¿Puedo usar SETI@home usando otro salvapantallas?
  5. ¿Funciona SETI@home a través de firewalls (o proxys)?
  6. Tengo SETI@home como salvapantallas, pero se interrumpe cada vez que comienza. ¿Que pasa?
  7. Tengo problemas conectando a Internet. ¿Que significan esos números?
  8. Soporta SETI@home la autentificación proxy?
  9. ¿Como cambio mi dirección de acceso o la información de usuario?
  10. ¿Porque sólo aparece una parte de la ventana SETI@home en mi pantalla?
  11. ¿Se sobrecargará o quemará mi CPU ejecutando SETI@home?
  12. Todavía tengo problemas conectando a través de mi Microsoft Proxy Server. ¿Que hago?
  13. Estoy ejecutando SETI@home version x.xx. Necesito hacer algo especial antes de acceder a una version superior?

Prestaciones y reconocimiento

  1. ¿Porque algunas unidades tardan muy poco en completarse?
    ¿Porque la barra de progresos salta al 100% sin completar el analisis?
  2. ¿Porque varían tanto los tiempos de completar el analisis en la versión 3.x?
  3. ¿En un ordenador con más de un procesador, el salvapantallas usa más de un procesador?
  4. Segun las estadísticas la plataforma X corre Y veces más rápido que yo!! ¿Porque?
  5. Cuando devuelvo mis resultados y obtengo una nueva unidad ¿Porque no están actualizados las "Unidades completadas" y el "Tiempo total de computador"?
  6. Estoy intentando acceder a mi cuenta pero he perdido mi contraseña. La dirección de e-mail que di al registrarme ya no es válida. ¿Pueden darme acceso de nuevo a mi cuenta?
  7. ¿Seré reconocido si mi computador detecta una señal?
  8. ¿Funciona más rápido SETI@home con más RAM (e.g., 256 MB en lugar de 128 MB)?
  9. SETI@home estaba a medio completar una unidad, pero el programa se ha resetado y vuelve a partir de cero. ¿Que pasa?

El proyecto

  1. ¿Porque no muestran el código de los programas?
  2. ¿Porque no lo hacen en Java?
  3. ¿Porque hacen un salvapantallas en lugar de un programa que funcione siempre en segundo plano?
  4. ¿Es SETI@home un buen modelo para el trabajo científico del futuro? Hay más ideas de proyectos similares?
  5. ¿Como se compara la potencia de Seti@home con los Supercomputadores existentes?
  6. ¿Cuando y donde alguien dijo "Eureka! Hey, podemos hacer estos analisis con los computadores que tiene la gente en casa"?

Windows

Más información sobre SETI@home y Windows se puede encontrar en páginas relacionadas.

  1. ¿Como puedo hacer que SETI@home sea más veloz?
  2. ¿Se puede proteger el salvapantallas de Windows con contraseña?
  3. SETI@home usa el 90% del tiempo de dos CPU. ¿Porque lo hace si no es multitarea?
  4. El computador dice "file open failed in state.txt." ¿Porque?
  5. ¿como se hace para desconectar el PC de Internet automaticamente despues de comunicar con el servidor de SETI@home?
  6. Tengo problemas conectando por Internet.¿Que significan esos números?
  7. Siempre que SETI@home intenta conectar al servidor, immediatamente da error
  8. ¿Como configuro el PC para que se conecte automaticamente ?
  9. ¿Puedo procesar la misma unidad una parte con la version gráfica y otra con la de comando?
  10. ¿Se va a realizar una version para las instrucciones G4/3DNow/etc.?
  11. ¿Existe una version que funcione como un servicio NT? ¿Como ejecuto SETI@home como un servicio NT?
  12. Encuentro muchas copias de "state.sah" en mi PC. ¿Que pasa?

Macintosh

Puede encontrar más información sobre Mackintosh en páginas relacionadas.

  1. ¿Que puedo hacer para que SETI@home sea mas rápido?
  2. How do I bring up the SETI@home application window?
  3. Cuando SETI@home (Mac) intenta conectarse al servidor, devuelve immediatamente un error.
  4. ¿Como configuro mi Mac para que se conecte automaticamente?
  5. ¿Porque estan las opciones de Preferencias, Ayuda y Login desactivadas a veces?
  6. ¿Puedo hacer funcionar SETI@home sin instalarlo como extension del sistema?
  7. Sometimes my computer seems to ignore mouse clicks or keystrokes while SETI@home is running.
  8. SETI@home seems to get very slow or even stop at times.
  9. Sometimes I cannot get SETI@home to run from its icon in the Menu Bar or using the hot key or sleep corner.
  10. How can I get my Macintosh to disconnect from the Internet automatically after communicating with the SETI@home server?
  11. I am having trouble connecting over the Internet. What do these error numbers mean?
  12. Are you planning on optimizing the SETI@home client for the G4/3DNow/etc instruction set?
  13. Are you planning on adding multiprocessor support for my Dual G4 system?

UNIX

Más información sobre SETI@home en UNIX en páginas relacionadas.

Plataformas

  1. Are there versions of SETI@home for parallel systems such as Beowulf or multiprocessors?
  2. Will there be a Windows 3.x version?
  3. Is there a version that runs as an NT Service?
    How do I run SETI@home as an NT Service?

SETI@home data distribution

  1. Will you ship larger chunks of data to faster computers?
  2. What happens to work units that never get returned by us? Are they lost forever?
  3. Can I use a disconnected PC?
  4. Can I use a seldom connected PC?
  5. If you don't get a result back from one PC how long does the server wait until sending the same data out again?
  6. How can I return my results but not get another work unit from the servers?

SETI@home science

  1. What happened to the gaussian information display in the new Mac and Windows clients? Are the clients still looking for gaussians?
  2. Why don't I see the new graphics for the gaussian fit calculations?
  3. What will happen if an extraterrestrial signal is detected?
  4. It says SETI@home will run for 2 years. Why not keep it going indefinitely?
  5. If you find a signal, how will you decode the information in it?
  6. How is data collected from the telescope and transmitted to other machines for analysis?
  7. What sorts of signals are being analyzed, and what form does the signal analysis take?
  8. How will the results of the calculations be merged again?
  9. Are there any safeguards in place that would prevent the sending of a false 'negative' interpretation of data, thus masking an extraterrestrial signal?
  10. What is to prevent someone from hacking the program and sending back false data that would interpret a signal as extraterrestrial?
  11. Is it likely that so many people sign up that you won't always have enough Arecibo data to feed all the clients? If so, how will this be handled?
  12. Why is curve fitting done for some FFTs and not others?

SETI en general

  1. ¿Que clase de espectro emite actualmente la Tierra? ¿Se puede ver esa señal a 10 o 50 años luz de distancia? Si SETI estuviera en un planeta a 10 o 50 años luz y alli utilizaran este proyecto, sería capaz de detectar la señal de la Tierra (si mirase en esta dirección)?

Si no encontró su pregunta en esta página, puede enviarnosla aquí.


¿Que necesito para participar en SETI@home?

Para sistemas Windows (95/98/NT) necesitaras un PC con mínimo 32MB de RAM, capacidad gráfica de 8bits en resolución de 800x600, 10MB de espacio en disco, y una conexión a internet. Para sistemasMacintosh necesitaras lo anterior, asi como in procesador PowerPC y Mac OS 7.5.5 o posterior. Se puede usar SETI@home en un portatil que se conecte ocasionalmente. Tambien soportamos muchas versiones de UNIX, incluyendo Linux en varias CPUs. Esperamos dar soporte a otros sistemas como OS/2 y BeOS. No aceptamos WebTV. No importa ni la velocidad de su CPU ni la velocidad del modem. tampoco importa el lugar del mundo dende viva.


¿Necesito saber algo de ciencia or de SETI para usar SETI@home?

No. Sólo necesitas descargar e instalar el programa.


¿Cuanto tarda en descargarse el salvapantallas?

Cerca de 5 minutos con un modem de 28.8Kbps


Pago por cada hora de conexión a Internet ¿Cuanto tiempo necesita SETI@home estar conectado?

SETI@home se conecta sólo para transferir datos. Esto ocurre cada varios dias y necesita unos 5 minutos (Lo puedes hacer mientras bajas el correo o navegas). El resto del proceso se hace estando desconectado.


¿Porque es un salvapantallas en lugar de un programa que funcione en segundo plano todo el tiempo?

SETI@home usa bastante memoria mientras se ejecuta y podría dar problemas en algun computador. nos queremos asegurar de que no tiene ningun efecto sobre el trabajo que realiza normalmente con su computador, por eso, para PC y Mac el modo por defecto es el de salvapantallas.

De todas maneras si ya tiene un salvapantallas favorito o prefiere no ver el salvapantallas, SETI@home puede tambien funcionar como programa en segundo plano funcionando todo el tiempo y sin gráficos. Así es como funciona la version UNIX


¿Porque no lo hacen en Java?

Todavía no es lo bastante rápido y muchos detalles que dependen del sistema necesitan estar hechos en C.


¿Que pasa con la seguridad?

El programa/salvapantallas solo se puede descargar desde esta página - No apoyamos a singun programa SETI@home obtenido en otro sitio. Este software envia y descarga datos sólo de nestro servidor aquí en Berkeley. El servidor de datos no descarga ningun código ejecutable desde su PC. Todo sea dicho, el salvapantallas es mucho mas seguro que el navegador de Internet que está usando ahora mismo !!!


Usará el salvapantallas más de un procesador en un computador multiproceso?

No la version inicial. Puede que la siguiente.


¿Porque no muestran el código fuente?

Hemos decidido no mostrar el código fuente por razones de seguridad y razones científicas. Todo el mundo tiene que hacer exactamente el mismo analisis, o no tendremos control sobre la investigación ni podremos confiar en los resultados. Tambien estamos preocupados por si alguien quiere hurgar deliberadamente en nuestra base de datos y servidor.


¿Como es de complejo el software? ¿Tienen que estar los usuarios encenciendo, apagando, enviando, los resultados? ¿Tiene que estar mi computador conectado todo el tiempo?

Los usuarios no han de hacer nada que no quieran. Los resultados pueden ser enviados automaticamente la próxima vez que el usuario se conecta a Internet (comprobando el e-mail, navegando, etc), o se puede hacer que pidan permiso cuando necesiten conectarse.


Funciona SETI@home a traves de firewalls (o proxys )?

SETI@home usa el protocolo HTTP, y trabaja cualquier firewall semi-transparente que permita trafico saliente de la Web. Las últimas versiones de SETI@home deberian trabajar a través de firewalls y proxys mas restrictivos

Si tiene problemas conectando desde Windows a traves de un proxy SOCKS, puede visitar SocksCap de NEC y Hummingbird Socks . Los dos le permiten usar software somo si estuviera "directamente conectado a Internet".

Si tiene algún problema conectando por protección de contraseña a traves de Microsoft Proxy Server, compruebe If you're having trouble connecting with password protection through Microsoft Proxy Server, check out Proxomitron

Si TODAVIA tiene problemas conectando a traves de un servidor proxy HTTP y está ejecutando SETI@home en una version antigua de Windows 95, Microsoft ha actualizado el driver de Winsock2 que corrige el problema, y permite que SETI@home se conecte. Busque "Windows Socket 2" en la sección de Información de Producto de la web de Microsoft. El fichero ocupa unos 986 kbytes, y supera al Windows 95 Service Pack 1.

Para más información de como instalar Proxomition haga click aquí.


I downloaded the software but my computer doesn't know what to do with a .tar (or .hqx or .sit or .exe) file - what do I do?

Windows software is packaged in files ending with .exe, Mac software with .sit or .hqx, and UNIX with .tar - chances are you have downloaded software for a system other than yours.


Los gráficos no se mueven. ¿No se quemará mi pantalla?

En la mayoria de los monitores, no. Para asegurarse, marque la opcion "Go to blank screen" en la opción Settings del salvapantalla.


Can I run this on as many machines as I like using the same SETI@home login?

Yes, you can - and as long as you use the same login on each machine, you'll get credit for them all.

Please note that you can (currently) only run one SETI@home process on a Windows or Mac machine, and if you are running multiple SETI@home UNIX processes, they must be running out of different directories. To setup these directories simply install the UNIX client as you normally do, but install into a different directory each time. Now you can run multiple SETI@home UNIX processes by starting one instance of the client from each SETI@home directory.


¿Que pasa con las unidades que nunca son devueltas? ¿Se pierden para siempre?

Hacemos un seguimiento de todas las unidades que se envian. Si tardan demasiado en volver, el servidor las envia automaticamente a otro usuario. Sólo cuando recibimos los resultados y los confirmamos el servidor borra la unidad del disco.


¿Puedo usar un PC sin conexion a Internet?

No. En teoria es posible transferir datos y resultados en disquette, pero no lo apoyamos. Compruebe la respuesta a la pregunta to question ¿Puedo usar un PC que se conecte rara vez?


¿Puedo usar un PC que se conecte rara vez?

Si. Compruebe los scripts: FetchCache y RunCache


If you don't get a result back from one PC how long does the server wait until sending the same data out again?

For quite a while now we have been sending the data out multiple times over the course of a day or so without waiting for a result at all. That allows us to delete the file from our local disks sooner than we otherwise would and keep our splitters generating data files at a high rate.


How can I return my results but not get another work unit from the servers?

Copy any file into your SETI@home Data directory and rename it "stop_after_send.txt". On the Macintosh, the "SETI@home Data" directory is in the Preferences folder, inside your System folder; on UNIX and Windows it is in the same directory as the executable file SETI@home.exe. If you later want to get a new work unit, remove the "stop_after_send.txt" file.


According to your stats page platform X is running Y times faster than my platform! Why?

This boils down to the vastly different speeds of different processors. As well, UNIX versions don't have any graphics (yet) and therefore run much faster. You can speed up the Mac and Windows processing by selecting your screensaver to "blank" after a few minutes, thereby reducing the graphics overhead. In addition, there was a bug in early Windows version (before 1.05) that caused it to report incorrect CPU times.


What happened to the gaussian information display in the new Mac and Windows clients? Are the clients still looking for gaussians?

The clients are still looking for Gaussions, however rather than display information about gaussions all the time, in newer clients the information only appears if the client has found a gaussian strong enough to report back to us.


I have SETI@home set to run as my screen saver, but it keeps getting interrupted right after it starts running. What's going on?

The SETI@home client may be being interrupted by another screen saver or screen saver-like program. As SETI@home is designed to be as noninvasive as possible by only using your computer while it is idle, if the client detects another program that wants to run, SETI@home will quit and step out of the way. If this other program is another screen saver or some other application that waits until your computer is idle before running, both SETI@home and the other program will try to run when the computer is idle causing SETI@home to quit. One common application which shows this behavior is McAfee VirusScan. If you have VirusScan installed, make sure that you have turned off the ScreenScan portion of the application as this will interfere with SETI@home.


How do I change my login address/user info?

If you need to change anything other than your e-mail address, you can use this web-based form: Account Change.

If you need to change your e-mail address, you must have access to the old account, since this is where we'll mail your password. If you don't have access to your old account, or you mis-typed your e-mail address when first logging in, you will have to log in again as a new user with the correct e-mail address.

For both security and administrative reasons, we cannot process any account changes unless you use the Account Change form.


Is the Windows screensaver password protected?

Our screensaver works just like any other screensaver, which includes the ability for the operating system to enforce password protection. This is done through the normal password protection channels.


SETI@home uses 90% of the time on two CPUs. Why does it do this if it's not multithreaded?

One CPU is doing graphics and the other is doing data analysis (so actually it is multithreaded, in a limited way).


My computer says "file open failed in state.txt." Why?

The most likely cause of this is Microsoft's "FastFind" utility. "FastFind" keeps a sorted index of all documents on the disk. While it generates this index it occasionally locks the file "state.txt." To avoid this error you may want to change the "FastFind" run interval to a large number like 999 hours. (To do that click on start->settings->control panel. Select FastFind. Click on Index and select 'Interval' and change the interval.)


¿Acepta SETI@home autentificación proxy ?

Si. Vea ¿Funciona SETI@home a través de firewalls (o proxys)?.


I am having trouble connecting over the Internet. What do these error numbers mean?

If you set "Ask me before connecting" in the Preferences dialog, SETI@home will display more detailed information for many errors.

Due to overwhelming interest in the SETI@home project, the server may intermittently be unreachable as too many clients are trying to connect. The server may also be occasionally down for maintainance. If you are unable to connect, please wait an hour and try again.


When I returned my results and got a new work unit, why were the "Data units completed" and "Total computer time" values not updated?

When we receive the results of a completed work unit at our server, it is transferred to a separate computer for processing. There may be a delay of up to a few days before the results are assimilated and verified. Your credit is updated only after verification of the work unit results data. Once the server has updated your statistics, your computer will receive the revised values the next time it connects to the server. This means that your displayed statistics will generally lag behind the work actually done.


Are there versions of SETI@home for parallel systems such as Beowulf or multiprocessors?

No. You can parallelize SETI@home by running multiple instances of it, either on a multiprocessor or on the nodes of a cluster. Just make sure that each instance runs in a different directory.


¿Habrá una versión para Windows 3.x?

No una gráfica. Podriamos hacer una version de comando DOS.


¿Hay alguna versión que funcione como servicio NT? ¿Como puedo ejecutar SETI@home como servicio NT?

no tenemos oficialmente una version que funcione como servicio NT, pero We don't officially have a version that runs as an NT service out-of-the-box, aqui tiene instrucciones sobre como hacer usted mismo que SETI@home funcione como servicio NT.


Encuentro muchas copias de state.sah y key.sah en mi computador. ¿Que pasa?

Esto no es un fallo de SETI@home, sino un virus ("hybris-b") que tiene este comportamiento. por favor descargue la última versión de antivirus y desinfecte sus sistemas.


¿Puedo ejecutar SETI@home mientras uso un salvapantallas diferente?

Si, en Preferencias , seleccione "Data Analysis Always Runs" Seleccione un salvapantallas diferente. SETI@home funcionara, incluso cuando su salvapantallas este funcionando.


Intento acceder a mi cuenta, pero he perdido la contraseña. La dirección de e-mail que use para registrarme ya no es válida.¿Existe alguna manera de tener acceso a mi cuenta?

Para proteger su cuenta de mofificaciones por otras personas, requerimos su e-mail y contraseña para acceder. Si pierde esta información, desafortunmadamente no podemos ayudarle a acceder a su cuenta ni resultados. Necesita crear una nueva cuenta con una dirección e-mail válida para acceder a cualquier reconocimiento futuro.


¿Que pasará si se detecta una señal extraterrestre?

Existe una Declaracion de Principios (Inglés) entre los investigadores SETI de todo el mundo. Primero, otros investigadores SETI tendran que verificar la señal independientemente. Si la señal es real y no puede ser explicada por fuentes humanas (satélites, reflejos, etc) entonces las agencias de prensa y gobiernos seran notificados de forma sistemática.


¿Si detecto una señal con mi PC me será reconocida?

Si, Nuestro software hace un seguimiento de donde se ha analizado cada fragmento. Si su computador forma parte de la deteccion usted será, si quiere, nombrado como co-descubridor.


Dicen que SETI@home funcionara durante 2 años. ¿Porque no sigue indefinidamente?

Debido a la gran respuesta y la alta calidad de los datos de analisis vamos a extender el proyecto más allá de los 2 años. Tambien extenderemos el proyecto para incluir datos de otras bandas de frecuencia, datos de un observatorio en el hemisferio sur, o ambos.


If you find a signal, how will you decode the information in it? Si encuentran una señal, ¿Como decodificarán la información ?

Nuestro objetivo es simplemente encontrar la señal. Si contiene informacion, se necesitaran expertos lingüistas o matemáticos para descifrarla.


How is data collected from the telescope and transmitted to other machines for analysis?

Data is recorded on high density tapes at the Arecibo telescope in Puerto Rico, about one 35 Gbyte tape per day, then mailed to Berkeley, then divided into 0.25 Mbyte chunks which get sent from the Seti@Home server over the internet to people around the world to analyze. Arecibo does not have a high bandwidth internet connection, so data must go by snail mail to Berkeley at first.


¿Harán fragmentos más grande de datos para los computadores más veloces?

No, todos los computadores reciben el mismo tamaño de archivos. Los computadores más rápidos los finalizan antes e immediatamente reciben un nuevo fragmento para trabajar, así les mantenemos siempre ocupados.


What sorts of signals are being analyzed, and what form does the signal analysis take?

We search for strong narrow band signals. It's like tuning your radio set to various channels, and looking at the signal strength meter. If the strength meter goes up, that gets our attention. More technically, it's a lot of digital signal processing, mostly Fourier Transforms at various chirp rates and durations.

We also search for pulsing and drifting signals, and signals which match the antenna beam pattern as the telescope slews across the sky. The analysis software searches for signals about 10 times weaker than any search done to date, because it makes use of a computationally intensive algorithm called "coherent integration" that no one else (including our Serendip program) has had the computing power to implement.


How will the results of the calculations be merged again?

They are merged in a database using our computers here, interference is rejected, and various pattern detection algorithms are applied to search for the most interesting signals.


¿Tienen algun sistema de seguridad que evite el envio de una interpretación "falsa" de datos, enmascarado como una señal extraterrestre?.

Si. Sin entrar en detalles (por motivos obvios) tenemos un mecanismo que detecta los falsos resultados.


¿Que hacen para prevenir que alguien manipule el programa y envie datos falsos que se puedan interpretar como señales extraterrestres?

Vea la pregunta anterior. De todas maneras no importaría - Si hay un "positivo" nosotros analizaremos ese fragmento para verificarlo.


Parece que hay tanta gente apuntándose que no siempre tendrán suficientes datos de Arecibo para todos los usuarios. ¿Que pasará si esto sucede?

Es posible. Llegados a ese punto, podremos enviar los mismos datos a más de un usuario e incluso, si podemos permitirnoslo, podemos poner otra unidad de grabado en Arecibo y grabar un campo más amplio de frecuencias (Nuestros sistemas actuales graban sólo 2.5Mhz del ancho de banda de 100Mhz de SERENDIP)


Will running SETI@home overload or burn out my CPU?

No. The CPU on most computers is always executing instructions (often the operating system's "idle loop") whenever the computer is turned on. It's no additional strain to execute SETI@home.


Why does only part of the SETI@home window appears on my screen?

In response to many requests from our users, SETI@home will now run on systems with screen resolutions smaller than 800X600 pixels. But if the window is larger than the screen resolution, parts of the SETI@home display window may extend off the edge of the screen; if this happens, move the window around to see all the data, or set the display to a higher resolution.


How can I make SETI@home run as fast as possible?

Select the "Blank screen after 1 minute" option under Screensaver Settings, and select "Data analysis always runs" in the Preferences dialog. Minimize the application window.

Will SETI@home run faster with more RAM (e.g., 256 MB instead of 128 MB)?

SETI@home uses about 16 MB of RAM while it's running. Beyond a certain point (typically 64MB, more if you run memory-itensive applications) more RAM won't make it run faster.


If I turn off my computer while SETI@home is running, will it lose any data?

No. SETI@home writes its results to disk every minute or two.


Why is curve fitting done for some FFTs and not others?

If time resolution does not yield 64 or more time bins, or if the slew rate is out of bounds, the curve-fitting routine is not called. In the curve-fitting routine, if a Power of Time array has no bin above 3 sigma, skip that array. For each bin (i.e., each candidate Gaussian) if amplitude not above 3.2 sigma (mean recalculated to exclude peak) skip that bin.


Why do some work units take very little time to complete?
Why did the progress bar suddenly jump to 100% only part way through the analysis?

Occasionally, a work unit will contain strong radio interference; these strong interfering signals typically come from satellites and radar from our own civilization. If the interference is very strong, the SETI@home program can not analyze that part of the spectrum, and after trying for a few minutes and detecting thousands of strong signals of earth origin, the program stops early in the processing and gets a new work unit. You will still get credit for the work done.


Why is there so much variability in workunit completion time with version 3.x?

With version 3.0, we introduced 2 new algorithms to search for pulsed signals. One is a generalized pulse finder and the other is a fast triplet finder. See for description of the algorithms. The generalized pulse finder, while highly optimized, is still very compute intensive. In order to balance sensitivity to pulsed signals (a good thing) with workunit throughput (also a good thing), the client will apply the pulse finder more often in some workunits than others.

The finer the time resolution (ie, the greater the number of bins in the time dimension), the more effective the pulse finding will be. The pulse finder always works with a chunk of data covering 1 telescope beam (0.1 degrees on the sky). For any given frequency resolution, the time resolution of 1 beam is determined entirely by the slew rate of the telescope at the time that the data were acquired. On one hand, the pulse finder does not bother with very coarse time resolutions and on the other, it avoids superfine time resolutions, as the execution time becomes prohibitively large. There is always a tradeoff and we have tried to achieve the optimal balance. Slew rate also affects whether or not the client executes the gaussian finder.

The following chart shows what gets executed at various slew rates. The corresponding angle range is also given. You can see the angle range for your workunit in the workunit header. The horizontal axis is frequency resolution in both FFT length and Hz. For any given slew rate / frequency resolution pair, you can see whether gaussian finding (G), pulse finding (P) or triplet finding (T) is executed.

slewrateangle_range128K64K32K16K8K4K2K1K512256128 6432168
--------------0.0750.1490.2980.5961.1922.3844.7689.53719.0738.1576.29152.59305.18610.351220.70
0.0000000.000000-----T--T--T-PT-PT-PT-PT-PT-PT-PT-PT-PT--T--T
0.0010000.107374--------T--T-PT-PT-PT-PT-PT-PT-PT-PT-PT--T--T
0.0020000.214748-----------T-PT-PT-PT-PT-PT-PT-PT-PT-PT-PT--T
0.0030000.322123---------G-TGPTGPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0040000.429497---------G--GPTGPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0050000.536871---------G--GPTGPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0060000.644246---------G--GPTGPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0070000.751620---------G--GPTGPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0080000.858994---------G--G--GPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0090000.966368---------G--G--GPTGPTGPTGPTGPTGPTGPTGPTGPTGPT
0.0110001.181117----------------PT-PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0120001.288491----------------PT-PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0130001.395865----------------PT-PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0140001.503240----------------PT-PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0150001.610614----------------PT-PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0160001.717988-------------------PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0170001.825362-------------------PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0180001.932736-------------------PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0190002.040111-------------------PT-PT-PT-PT-PT-PT-PT-PT-PT
0.0200002.147485-------------------PT-PT-PT-PT-PT-PT-PT-PT-PT


What sort of spectrum is currently being emitted by earth? Is that signal visible say 10 or 50 light years away? If SETI were on a planet say 10-50 light years from here and running this project there, would it be able to detect earth's signal (assuming it was looking in our direction)?

Earth is polluting space with radio and television signals that might be detected by nearby advanced civilizations, but it would be difficult for such a civilization to discover these signals if they only have Earth's current level of technology (eg: if they have an Arecibo like telescope and SETI@home like search).

Early TV shows like I Love Lucy and Ed Sullivan left the earth about 40 years ago, so have gone out 40 light years, reaching several thousand nearby stars. But these signals are relatively weak and SETI@home is not likely to detect the equivalent of Earth type TV transmitters, even on the nearest stars.

Earth's strongest transmitters might be somewhat easier to detect, such as those emitted by military radars, or some radio telescopes. The Arecibo telescope transmits very powerful signals when it is used as a radar system to study planets, asteroids and the ionosphere. These radar signals are powerful enough to be detected 10,000 light years away by searches like SETI@home, except for three big caveats:

a) The Arecibo transmissions are in a very tight beam (they are not omnidirectional, like TV and military radar), so they only cover a very small part of the sky at once (about a millionth of the total sky). It's is unlikely another civilization will be within one of these narrow beams.

b) The Arecibo transmitter's oldest signals left Earth about 30 years ago, so have only travelled 30 light years.

c) SETI@home is not searching the band of frequencies that the Arecibo transmitters utilize (although our older SERENDIP III program did survey one of those bands).


How do I bring up the SETI@home application window?

Click on the SETI@home icon in the Menu Bar and select Launch.


Whenever SETI@home (Mac) tries to connect to the server, it immediately gets an error.

First, select "Proxy Settings" from the menu and check that they are correct.

If that is not the problem, then try this: Set "Ask me before connecting" in the SETI@home Preferences. Manually tell your computer to dial the Internet. Then select "Connect Now" from the SETI@home menu while your computer is connected to the Internet. (To dial manually, use the OTPPP, Remote Acess or FreePPP control panel.)

If this solves your problem, your computer's Internet software may be incorrectly configured. Instructions for setting this up are given under How do I set up my Mac to connect automatically?.


How do I set up my Mac to connect automatically?

Macintosh dial-up Internet software comes in 2 flavors, Open Transport and FreePPP. On OS 9, Open Transport is called "Remote Access". If you are using Open Transport (OTPPP or "Remote Access"), then:

1) Under the Apple menu, select Control Panels and PPP ("Remote Access" in OS 9). make sure it has the correct phone number of your ISP, login name and password. To connect unattended, you must have "Save password" set.

2) Press the "Options" button, then select the "Connection" tab. Set "Connect automatically ..." and "Disconnect if idle for xx minutes". Set the disconnect delay to whatever number you wish.

3) You may also set the "prompt every xx minutes" checkbox if you wish. If the computer is unattended, so there is no response to the reminder, it will go ahead and disconnect after a few minutes.

If you are using FreePPP, then:

1) Find and open the FreePPP Setup application. Select the "General" tab.

2) Set "Allow applications to open connection" and "Disconnect if idle for xx minutes". Set the disconnect delay to whatever number you wish.


Why are the Preferences, Help and Login menu items sometimes disabled?

These are disabled while SETI@home is transferring data over the Internet, as they could interfere with the transfer.


Can I run SETI@home without installing it as a system extension?

Yes. Move the SETI@home icon out of the System Folder : Control Panels folder, to another location (such as the desktop), and restart your Macintosh. You can run SETI@home as a stand-alone application whenever you wish. But if you have another screensaver installed, SETI@home will run very slowly when the other screensaver is active, and the other screensavers animation may be sluggish or jerky.


Sometimes my computer seems to ignore mouse clicks or keystrokes while SETI@home is running.

Response to user input may be a bit sluggish on Macintosh models with slower processors (prior to G3), or with less than 32MB of physical RAM. You may sometimes need to hold the mouse button over the Menu Bar for a few seconds before getting a response.


Sometimes I cannot get SETI@home to run from its icon in the Menu Bar or using the hot key or sleep corner.

SETI@home will not launch if another application has a modal dialog frontmost. The Standard File (Open and Save) dialogs are examples of modal dialogs. You must dismiss the modal dialog for SETI@home to launch.


SETI@home seems to get very slow or even stop at times.

Different portions of the same work unit can vary greatly in speed. If progress seems to freeze, be patient and let it run overnight. It may have gotten past the slow spot by then.


What can I do to make SETI@home run faster?

Here are some suggestions:


How can I get my Macintosh to disconnect from the Internet automatically after communicating with the SETI@home server?

Dial-up Internet software comes in 2 flavors, Open Transport and FreePPP. If you are using Open Transport (OTPPP), then:

1) Under the Apple menu, select Control Panels and PPP. make sure it has the correct phone number of your ISP, login name and password. To connect unattended, you must have "Save password" set.

2) Press the "Options" button, then select the "Connection" tab. Set "Connect automatically ..." and "Disconnect if idle for xx minutes. Set the disconnect delay to whatever number you wish. 10 minutes is a good value.

3) You may also set the "prompte every xx minutes" checkbox if you wish. If the computer is unattended, so there is no response to the reminder, it will go ahead and disconnect after a few minutes.

If you are using FreePPP, then:

1) Find and open the FreePPP Setup application. Select the "General" tab. (If you don't see the "General" tab, click the small triangle in the lower left corner.)

2) Set "Allow applications ot open connection" and "Disconnect if idle for xx minutes". Set the disconnect delay to whatever number you wish. 10 minutes is a good value.


How can I get my PC to disconnect from the Internet automatically after communicating with the SETI@home server?

1) From the Start button, select "Settings" and then "Control Panels". Open the "Internet Options" Control Panel.

2) Select the "Connections" tab. Make sure the desired "Dial-up networking" selection is set as the default. (The set default button will be grayed out if you select the current default in the list.)

3) Set "Always dial my default connection".

4) Select the correct "Dial-up networking" from the list, and click on the "Settings..." button.

5) Another dialog box "xxxx Settings" appears. Press the "Advanced" button.

6) The "Advanced Dial-Up" dialog will appear. Set "Disconnect if idle for xx minutes" Set the disconnect delay to whatever number you wish. If you wish, you may also set "Disconnect when conection may be no longer needed.


I am having trouble connecting over the Internet. What do these error numbers mean?

If you set "Ask me before connecting" in the Preferences dialog, SETI@home will display more detailed information for many errors.


Whenever SETI@home tries to connect to the server, it immediately gets an error. (Windows)

First, select "Proxy Settings" from the menu and check that they are correct.

If that is not the problem, then try this: Set "Ask me before connecting" in the SETI@home Preferences. Manually tell your computer to dial the Internet. Then select "Connect Now" from the SETI@home menu while your computer is connected to the Internet. (To dial manually, select Start -> Programs -> Accessories -> Dial-Up Networking, and double-click the desired connection.) If this solves your problem, your computer's "Internet Options" control panel may be incorrectly configured. Instructions for setting this up are given under How do I set up my computer to connect automatically?.

If your PC does not have a relatively recent version of Internet Explorer, you may not have the software needed for SETI@home to dial your modem. IE versions 4 and later install the needed software; we have not tested with older versions of IE. The needed file is c:\WINDOWS\SYSTEM\wininet.dll.


How do I set up my computer to connect automatically? (Windows)

For Windows 95 and 98, do the following steps:

1) From the Start button, select "Settings" and then "Control Panels". Open the "Internet Options" Control Panel.
2) Select the "Connections" tab. Make sure the desired "Dial-up networking" selection is set as the default. (The set default button will be grayed out if you select the current default in the list.)
3) Set "Always dial my default connection".
4) Select the correct "Dial-up networking" from the list, and click on the "Settings..." button.
5) Another dialog box "xxxx Settings" appears. Press the "Advanced" button.
6) The "Advanced Dial-Up" dialog will appear. Set "Disconnect if idle for xx minutes" Set the disconnect delay to whatever number you wish. If you wish, you may also set "Disconnect when conection may be no longer needed."
7) Close the "Internet Options" Control Panel.
8) Double-click on "My Computer", and then on "Dial-Up Networking". Double-click on the default "Dial-up networking" icon. Make sure the "Save password" box is checked. If not, check it and click on "Connect", then "Cancel". Close the dialog.

For Windows NT do this: 1) Click Start, point to Programs, point to Accessories, and then click Dial-Up Networking.
2) Click More, and then click User preferences.
3) In the Enable Auto-Dial By Location dialog box, select each location for which you want the automatic dialing feature to operate.
4) Click OK and then restart the computer.


Can I process the same work unit on Windows partly with the graphical version and partly with the command-line client?

No. Due to our new security measures to prevent falsified results, if a work unit has been partly completed by a different version of SETI@home, the progress will be reset to zero and the work unit will be processed from the beginning.


Why don't I see the new graphics for the gaussian fit calculations?

After each pass over the data, SETI@home does a preliminary check to see if the data's properties indicate a possible gaussian curve. If not, it saves time by skipping the gaussian analysis. For some work units (those with slow slew rates), no gaussian fit calculations are done for the entire work unit, so this area of the display remains empty.


SETI@home was part way through processing a work unit, but then progress reset to zero and it started again from the beginning. What happened?

There are several possibilities. If you have SETI@home set to connect automatically to the Internet, it may have returned the result and gotten a new work unit. (If a work unit has too much radio interference or RFI, then SETI@home may request a new work unit much sooner than usual.)

If SETI@home's processing was interrupted abnormally by a system error or power interruption, its output files may have been corrupted. In this case, SETI@home will restart the work unit from zero automatically.


I'm still having trouble connecting through my Microsoft Proxy Server. What do I do?

If you're having trouble connecting with password protection through Microsoft Proxy Server, check out Proxomitron: http://members.tripod.com/Proxomitron/.

Please be aware that Proxomitron is third party software, and therefore out of SETI@home control, but it has been recommended by various users including Nick.Roux@Bigfoot.com who posted these cookbook instructions on the sci.astro.seti newsgroup (thanks, Nick!):

1. Download Proxomitron (at http://members.tripod.com/Proxomitron/) and install it.

2. Go to 'Headers", find 'Proxy-Authorization', select 'In' and 'Out' and click on 'Edit'. In the 'Replacement Text' field enter 'basic user:password' replacing user and password with your userid and password for the your MS Proxy server. Highlight user:password and rightclick on it. Select 'Mime Encode', 'Encode String'. The 'Replacement text' field should now look something like 'basic dXNlcjpwYXNzd29yZA=='

3. Click OK, OK

4. Click on 'Proxy' and add the name:port of your MS Proxy Click OK

5. Select the 'Use Remote Proxy' Checkbox Save your changes.

6. In S@H select Settings/Proxy Server and add 'localhost', port 8080 as your proxy.

Now Proxomitron will automatically sign on to the MS Proxy.


Are you planning on optimizing the SETI@home client for the G4/3DNow/etc instruction set?

As of yet, there are no plans to optimize the SETI@home client for any particular platform or processor. Future versions of the client may be optimized, but there are no plans for doing so in the immediate future.


I'm running SETI@home version x.xx. Do I need to do anything special with this version before I can upgrade to a higher version?

No. The SETI@home installer automatically detects old versions and performs the necessary adjustments.


Are you planning on adding multiprocessor support for my Dual G4 system?

Yes. Not in 3.0, but in a later version.


Is Seti@home a good model for future scientific work? Are any other such project ideas floating around?
Several companies have recently been formed to pursue this idea, and dozens of tasks (ranging from genome analysis to financial analysis) have been proposed.
How does the computing power of Seti@home compare with existing supercomputers?
The most powerful computer, IBM's ASCI White, is rated at 12 TeraFLOPS and costs $110 million. SETI@home currently gets about 15 TeraFLOPs and has cost $500K so far.
Cuando y donde alguien exclamó "Eureka! Hey, podemos hacer este tipo de analisis con los computadores que tiene la gente en casa"?
Apareció en una conversación entre David Gedye y Craig Kasnoff en una fiesta de navidad en Seattle en Diciembre de 1994. Podría haber existido antes. it may have existed before that.
Al principio

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