D-Day Minus Three

We are in the last three days of worried house-packing, but I can’t resist taking time to show you this evening’s sky –

evening sky 2016 Apr 13

The great constellations of winter nights are still arrayed, though in tilted attitude, above the sunset horizon of spring, and among them is the D-shaped Moon.

(Don’t forget that you can click and right-click to see these images larger; at least that’s the way it works for me.)

The moment of First Quarter is 4h Universal Time on April 14, which is 11 PM on the 13th by eastern American clocks.  The Moon, passing 11 degrees south of Pollux, happens to be almost exactly at its mean distance from us, being half way between a New moment that closely coincided with perigee (Apr. 7) and a Full (Apr. 22) close to apogee – as is made clear by the “Moon’s distance” graph in Astronomical Calendar 2016.

And I can only just resist telling you where we are aiming to land on April 16.  Not on the Normandy beaches and not on the Moon, but another point with astronomical significance; I’ll reveal it after we get there, if we really do.

 

11 thoughts on “D-Day Minus Three”

  1. Oh, by the way, I saw the waxing crescent Moon through clouds yesterday evening. When I looked with binoculars I could see the darker maria and lighter highlands, but no craters. Just below the Moon, Alhena was visible through binoculars but not to the unaided eye. I poked around with the binoculars and could see Pollux and Castor, Menkalinan and Capella, Procyon, Orion’s belt, Aldebaran and the brighter Hyades, the Pleiades, Betelgeuse, and Sirius (in that order — the clouds were thicker over toward Sirius). Rigel was below the tops of the buildings across the street.

    It was surprisingly enjoyable to just barely see those bright stars through the clouds. Sometimes when I’m disappointed by clouds interfering with my skywatching, I remind myself that if we were to see our humble earthly clouds from light-years filling the eyepiece of a telescope, they would look quite beautiful.

    1. We had the slightly strange experience three nights ago of seeing all those stars down to Procyon but absent Sirius; there appeared to be no decrease in clarity of the sky down to the horizon, but the combination of slightly increasing haze and light pollution just pushed the brightest star below the level of discernment.

  2. You appear to be landing on a Golf Course in the north of Philadelphia.

    Martin of Ribaute (France)

    1. I didn’t get it for a moment – then I realized you’re referring to the place at 40 north, 75 west, the default latitude and longitude for these horizon scenes that I draw. Clever of you, especially since I neglected this time to include the label “horizon for latitude 40 north” (for a programming reason, which I’ve now seen to).

      I’ve been using Philadelphia as standard location for years, without bothering to check where the exact 40-north-75-west point is; now, using Google Earth, yes, I see that golf course. But it’s actually east of the river, in Cinnsminson, New Jersey, isn’t it?

      I’ve wondered whether to use 90 west as the default longitude (as Sky & Telescope now does), since that’s nearer the middle of the US and is also simpler geometrically. Constantly using the Eastern time zone is a bit unfair on those over in the west. However, 75 west is more central if you’re considering a broader selection of the English-speaing world.

      Anyway, I’m not moving to either of those longitudes, but, in a way, to no longitude.

      1. The asteroid 2830 Greenwich, perhaps? If so, be careful — it’s less than 10 km in diameter, so has very low surface gravity! If you jump with joy, you’ll go into orbit.

        1. Will be nice when we can live on an asteroid and grow some of those trees that, as Freeman Dyson imagined, could grow outward for miles.

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