Comments Policy

  • Generally, anyone may post comments.
  • This is a G rated site.  No profanity.
  • Nonsense comments, or commercial comments will be deleted.
  • URLs to your website and blog are welcome if they are non-commercial sites.  The URL and/or comment may be deleted if they violate these rules.
  • I use the Akismet spam filter which stops most of the offenders on the last two points.  Currently the spam rate is low enough that I can review them individually before allowing them to be displayed.  Should the spam level rise much higher, I will give the spam filter the ability to delete suspicious comments without my intervention.

Bob

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  1. jim fantozzi
    August 29, 2011 at 3:59 pm

    bob the open space night of the 27th was spectacular only problem i couldnt stay to see jupiter i felt like i was a 10 year old kid again im (59) ive been published in sky and telescope and astronemy for wide field pics and have had a few scopes in my day. i looked threw a 10 dob a little while ago and the view was awsome even my wife was impressed. i cant wait to look threw the 25 inch will you guys be back at the open space in september if so please let me no

  2. Carolyn Sutton
    January 13, 2015 at 12:36 pm

    Do you have a 2015 calendar and/or book ( like a farmers almanac) for purchase??

  3. Alisha Cochrun
    March 6, 2015 at 1:21 pm

    Bob-
    I’m trying to help a friend find a star that was recently registered in honor of a loved one who suddenly passed away. The star is located within the realm of ursa major, outside of the bowl and towards the head of the constellation. If you have time, can you please direct me to a comprehensive and basic sky chart that I could use to find it this time of year? I understand conditions are not supposed to be ideal and the chances of me finding it are without a telescope are extremely slim, but I sure would like to try. Any help would be much appreciated; again at your convenience and thank you!

    • March 6, 2015 at 4:52 pm

      Hi Alisha,

      I’m sorry, I cannot help you. None of the commercial star registries are official. The only official governing body for celestial nomenclature is the International Astronomical Union (IAU), and they don’t sell star names. You can go to http://www.iau.org/public/themes/buying_star_names/ where they cover the topic. Here is a quote from the page:

      “As an international scientific organization, the IAU dissociates itself entirely from the commercial practice of “selling” fictitious star names or “real estate” on other planets or moons in the Solar System. Accordingly, the IAU maintains no list of the (several competing) enterprises in this business in individual countries of the world. Readers wanting to contact such enterprises despite the explanations given below should search commercial directories in their country of origin.”

      The easiest star charts to get would be to download Stellarium from http://www.stellarium.org and zoom in to Ursa Major. The star names for the brighter stars do display. Most are Arabic from 1,000 years ago and pre IAU. Click on a star and you will get a Hipparchos .catalog number (HIP xxxxxxx).

      By the way the Big Dipper and Ursa Major is high in the northeastern sky these March evenings.

      However – Keep looking up!

      Bob

  4. Richard Fidler
    March 25, 2015 at 8:56 am

    On the equinox is the sun up 12 hours all over the Earth? You said here day length would be 12h 6m on the first day of spring. How would it be at the poles? Is the “equinox”–“equal night” a misnomer?

    • March 25, 2015 at 5:03 pm

      The poles, are of course, an exception because they are on the axis of the Earth, so the Sun doesn’t rise of set as a consequence of the Earth’s rotation. On an equinox the Sun would rise or set due only to the fact that the Sun is moving north or south of the celestial equator. The other odd place is on the equator, in which every day is an “equinox” with 12 hours day and night.

  5. Richard Fidler
    March 27, 2015 at 12:52 pm

    At the poles would the sun travel around the horizon at the vernal equinox on March 20? In the North, it would continue to get higher in the sky as we progress towards the solstice, rising to be 23 degrees above the horizon at that time? In the South, it would disappear below the horizon tip September 20?

    • March 30, 2015 at 1:59 pm

      Your statements are pretty much correct. The last sentence, you don’t mean the south pole do you? If you do, then that’s wrong. At the south pole daylight starts on the September equinox. If you mean south as a direction, then remember from the north pole, all directions are south. One additional note though, the September equinox is generally on September 23rd. Due to the eccentricity of the Earth’s orbit, and the fact that perihelion, Earth’s closest approach to the Sun, is in early January; and aphelion is in early July, the Earth’s orbital velocity varies a bit, making summer longer by 4 days than winter in the northern hemisphere.

  6. Richard Fidler
    March 30, 2015 at 3:29 pm

    Thanks for the correction. I should have said that on or about Sept. 20, the sun would appear for the first time at the South pole and would get higher and higher in the sky until the December solstice.

  7. Richard Kraemer
    April 26, 2015 at 5:31 pm

    Question: when is Venus at its brightest from earth? I know, at night. The outer planets would be brightest when nearest the earth and with the sun shining from over your back shoulder when viewing the planet, but Venus is farthest away when full, and is eclipsed when nearest? When in the arc does it reflect the most to us? (Does light shining through Venus’ atmosphere produce any rainbows for earth?

    • April 27, 2015 at 2:46 am

      Hi Richard,

      The point in Venus’ orbit is called greatest brilliancy. I googled: Venus greatest brilliancy to make sure. Venus does vary its distance quite a bit, from superior conjunction with the Sun, when its the farthest from us and full, to it closest at inferior conjunction, between the Earth and the Sun, when it shows a disk larger than Jupiter. However that disk is mostly unilluminated. Greatest brilliancy, according to what I read is the point that the illuminated part of Venus covers the greatest area of the sky. As a rule of thumb it occurs about 34 days before and again 34 days after inferior conjunction. It’s when Venus appears as a big crescent.

      BTW: When Venus passes in front of the Sun, the event is called a transit, not an eclipse because Venus doesn’t appear large enough to cover the Sun. We recently had two, in 2004 and again in 2012. You won’t live long enough to see the next ones, which will occur in the 22nd century. Sometimes Venus can be photographed when it appears very near the Sun at inferior conjunction. Venus’ atmosphere is so thick that the thin crescent extends completely around the planet.

      Keep looking up!

      Bob

  8. Richard Fidler
    July 4, 2016 at 8:41 pm

    Question: On the equinox the sun rises due east and sets due west. After the vernal equinox the sun rises north of due east and sets north of due west. By the June solstice, how many degrees does it rise and set north of the east-west line? Would it be 45 degrees because we are on the 45th parallel?

    • July 9, 2016 at 9:15 pm

      Not quite. At the location I write the blog for, 44.75 degrees north latitude, the Sun rises and sets 35 degrees north of the east-west compass points on the summer solstice.
      Even at the equator the sunrise/sunset point is 23.5 degrees north of the east-west compass points on that day. Just below the arctic circle near 66.5 degrees north on the summer solstice the sun will set then rise in the north, 90 degrees from the west and east line. It’s not a linear thing.

      • Richard Fidler
        July 10, 2016 at 8:07 am

        So at the arctic circle on the summer solstice if the sun rises and sets 90 degrees from the east-west line, that would mean that it touches the horizon due north when it “sets” and rises immediately from that point. Is that right?

  9. Carolyn Sutton
    December 22, 2016 at 12:11 pm

    I’m looking for the 2017 monthly Calendar of daily moon and sunrises and sets.

    • December 22, 2016 at 7:31 pm

      Rising and setting event times of the Sun and Moon are dependent on the location for which they are created. I have created such calendars, as tabular lists for several locations in the Interlochen Public Radio area. I only display moonrise or moonset, whichever occurs between sunset and sunrise, since these events are only visible at night. Go to http://ephemeris.bjmoler.org and click on Calendars. The 2017 calendars will be out near January 1st.

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