Important notice concerning e-mail!
We are being overwhelmed by e-mails, and simply cannot keep up with them all. In the past we've always tried to answer all messages received, but this is becoming impossible. Unfortunately, we must start being selective in the messages we answer, and below you will find a list of the types of question that we'll try to answer, and those which we won't. PLEASE be sure to read through the FAQ before sending a message. It might well be that the question is answered here, or there is a link to further sources of information. With your cooperation, we will have to spend less time answering e-mails and can spend more time productively improving the site.

General
      What types of e-mail are acceptable?
      What types of e-mail are unacceptable?

Observing satellites during a total eclipse of the sun
      Are satellites visible during a total eclipse of the sun?
      Can I get predictions of satellites or Iridium flares during an eclipse?

Setting up your observing location
      How accurately do I need to enter my coordinates?
      How do I convert angles from degrees, minutes and seconds to decimal degrees?
      Will I have to do anything when we change to/from daylight saving time to winter time?
      How do I save changes I make to my location?

Satellite predictions
      Why are satellites not visible in the middle of the night?
      Are the times given in local time or UTC?
      Why do passes for the Shuttle and ISS sometimes appear on the special pages for these two bright satellite, but not on the "All satellites" page?
      Why do some satellites tumble?
      Can I get predictions for times other than those available on the home page?
      Do the predictions include interplanetary spacecraft making earth flybys?
      I think I saw a bright satellite which could be the ISS but the prediction wasn't in the GSOC list. What could it be?
      How do you estimate the brightness of a satellite?

Iridium flares
      What is an Iridium flare?
      I saw a predicted flare, but it wasn't as bright as I was expecting. Why not?
      The flare I went out to see didn't appear. What was the reason?
      While I was out waiting for a flare or other satellite to appear, I saw another flare which wasn't in the predictions. What could it have been?
      While obeserving one of the predicted flares, I saw another one just a few seconds before or after the predicted one in almost the same place. Why?
      Why is the direction of an Iridium flare sometimes opposite to the direction to the flare centre? Which way should I look?
      Why did the Iridium flare I saw appear much higher in the sky than was predicted?
      Can I get predictions for times other than those available on the home page?

Whole sky chart
      I am having problems printing the sky chart, what can I do?
      Can I get black stars on a white background to save printer ink?
      Why does the sky chart have east on the left and west on the right?

Developed and maintained by Chris Peat, Heavens-Above GmbH Please read the updated FAQ before sending e-mail.