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Thread: Planetary Calendar for 2020

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    Planetary Calendar for 2020

    Planetary Positions for 2020 are attached, by right ascension, with eclipses and lunar nodes.

    This year has the first gas giant conjunction for almost a decade, between Jupiter and Saturn at the December solstice.

    As the diagram shows, Jupiter and Saturn are also currently conjunct to Pluto.

    A visual highlight is the quadruple conjunction between Mars, Jupiter, Saturn and the Moon in the morning sky on 19 March, with Pluto also in the background.
    Attached Images Attached Images

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    In an unusual event, all the outer planets are retrograde for one day, from September 11 to 12.

    This can only happen during the two month period every two years when Earth passes between the Sun and Mars, and when all the other outer planets are within an arc of about 120 degrees containing the solar opposition point of dusk rising.

    Mars went retrograde today, and Jupiter turns forward tomorrow.

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    Quote Originally Posted by Robert Tulip View Post
    Planetary Positions for 2020 are attached, by right ascension, with eclipses and lunar nodes.

    This year has the first gas giant conjunction for almost a decade, between Jupiter and Saturn at the December solstice.

    As the diagram shows, Jupiter and Saturn are also currently conjunct to Pluto.

    A visual highlight is the quadruple conjunction between Mars, Jupiter, Saturn and the Moon in the morning sky on 19 March, with Pluto also in the background.
    A nice diagram but I'm a little confused by the time of these events. For example on the Mars curve what time of day does the curve represent? I'm in CDT and I see Mars in the sky ~2100.

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    Quote Originally Posted by bknight View Post
    A nice diagram but I'm a little confused by the time of these events. For example on the Mars curve what time of day does the curve represent? I'm in CDT and I see Mars in the sky ~2100.
    Well, the time doesn’t really matter for casual observing. The retrograde motion occurs over a few weeks as Mars wanders through Pisces. In November Mars starts to move back to the west.

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    Quote Originally Posted by schlaugh View Post
    Well, the time doesn’t really matter for casual observing. The retrograde motion occurs over a few weeks as Mars wanders through Pisces. In November Mars starts to move back to the west.
    If one views a planet at say 2100 versus 0600, then I would say the time of day to observe does make a difference, unless I don't understand the chart.

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    Quote Originally Posted by bknight View Post
    If one views a planet at say 2100 versus 0600, then I would say the time of day to observe does make a difference, unless I don't understand the chart.
    Hang on - before we get to time of day, this chart seems to be incorrect; it shows Mars sitting in Aries but Mars is currently in Pisces. Maybe an old chart?

    So let's use this chart anyway (right or wrong) and you'll see that it doesn't have time of day noted; the chart shows in which constellation a planet sits on a given day and month. And of course it takes a number of days and weeks for a planet to move between the constellations of the Zodiac.

    If you look at the curvy red line for Mars at the bottom of the chart, it shows that Mars is in Aires (the ram symbol is to the far left down the left-hand axis) for several months, until the end of the year. The curvature comes from Mar's retrograde motion as it moves back and forth within Pisces.

    If you find the straight red line for Mars for June 21, you'll see that it was sitting in Sagittarius.

    And again, this chart seems to be wrong. See this for up-to-date information on the planets: https://www.heavens-above.com/PlanetSummary.aspx

    ETA: Mars was in Aries in September 2005.

    ETA2: Or else the constellation symbols have been shifted. The planet positions relative to the dates seem to be correct.
    Last edited by schlaugh; 2020-Sep-11 at 06:25 PM.

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    Ok using the chart you linked, the Mars Altitude -s -(negative) 13.8 degrees which means to me it is below the horizon. Jupiter and Saturn are +65.7 degrees. That is where I believe I see them at ~2100. Now once the Earth turns about 9 hours (2100-0600) I am unable to see them. Now with the Mars information below the horizon (my interpretation) it should be above the horizon at 0600 and yes I believe I can see it in the morning. So what am I missing? in the chart(s), to be able to view them with the naked eye as I don't own a telescope.

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    The chart can’t tell you rise and set times, just position in the sky relative to the zodiac. It’s too coarse for that kind of prediction.

    In that same site I linked, look for the “home” link, click that, and then bring up the Interactive Sky Chart. That chart defaults to GMT.

    In there you can tweak the dates and times to see the sky at that point. And you can select your location for even more accurate results.

    ETA: Sorry! It's been a long day and I misread your last post. Yes, the chart I linked to CAN show you a wealth of detail including rise and set times specific to your location or defaulting to GMT. For Houston, Mars rises at 21:29 and sets at 10:02, so absolutely can be seen at 06:00. If you can bring up the sky chart I mentioned it should show you Mars in the sky and relative to other objects. Here's a screen grab of the chart for what you would have seen this morning.

    Sky Chart.png
    Last edited by schlaugh; 2020-Sep-11 at 11:32 PM.

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    Quote Originally Posted by schlaugh View Post
    Hang on - before we get to time of day, this chart seems to be incorrect; it shows Mars sitting in Aries but Mars is currently in Pisces. Maybe an old chart?

    So let's use this chart anyway (right or wrong) and you'll see that it doesn't have time of day noted; the chart shows in which constellation a planet sits on a given day and month. And of course it takes a number of days and weeks for a planet to move between the constellations of the Zodiac.

    If you look at the curvy red line for Mars at the bottom of the chart, it shows that Mars is in Aires (the ram symbol is to the far left down the left-hand axis) for several months, until the end of the year. The curvature comes from Mar's retrograde motion as it moves back and forth within Pisces.

    If you find the straight red line for Mars for June 21, you'll see that it was sitting in Sagittarius.

    And again, this chart seems to be wrong. See this for up-to-date information on the planets: https://www.heavens-above.com/PlanetSummary.aspx

    ETA: Mars was in Aries in September 2005.

    ETA2: Or else the constellation symbols have been shifted. The planet positions relative to the dates seem to be correct.
    The chart is correct. The IAU measures planetary positions according to the tropical zodiac, with the first point of Aries defined as the intersection of the celestial equator and the ecliptic. This is the basis for stellar and planetary positions of right ascension as used in this chart. The sign of Aries in the chart is used to indicate the first thirty degrees of right ascension. Due to precession of the equinoxes, the first point of Aries has moved 27 degrees through Pisces over the last 2000 years. Therefore you are correct to note that Mars is now in the sidereal constellation of Pisces, but wrong to suggest the chart is incorrect. The tropical location of Mars in Aries is correctly shown in the chart.

    It is easy to calculate time of rising of each planet on this chart by its distance from the sun. When planets are conjunct the sun they rise at dawn and when they are most distant from the sun they rise at dusk.

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    My apologies, your further explanation clarifies my confusion.

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    Quote Originally Posted by schlaugh View Post
    My apologies, your further explanation clarifies my confusion.
    Hi Schlaugh, I agree precession can make finding the planets rather confusing, so thank you for raising your question. It would be easier if the right ascension and sidereal measurements lined up. Precession means planetary positions shown in the chart attached to the opening post need subtraction of about 27 degrees of arc to locate them against the stars.

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