SKYLIGHTS
Astronomy news for the week starting Friday, June 16, 2000.
We begin the week with the Moon at its full phase on Friday, June
16, the phase reached shortly before moonrise in North America, the
Moon therefore rising just a bit after sunset.
The big news of course is of the Earth and the beginning of
northern hemisphere summer (and southern hemisphere winter). At
8:48 PM Central Daylight Time (9:48 PM Eastern Time, 6:48 PM
Pacific Time) on Tuesday, June 20, the Sun will pass across the
Summer Solstice in Gemini (after sunset on the East Coast of North
America, before sunset on the west coast). At that moment, the
northern end of the Earth's axis is tipped directly toward the Sun
and the Sun will be as far north as possible, 23.43 degrees north
of the celestial equator. On that day, the Sun will appear
overhead at the Tropic of Cancer (23.43 degrees north latitude) and
everywhere on Earth except in the arctic regions, the Sun will rise
and set as far to the north as possible. At all points from the
arctic circle north, the Sun will be circumpolar, that is, it will
not reach the horizon, resulting in a day of 24 sunlit hours.
Conversely, below the antarctic circle, the Sun will not rise at
all.
Because the June full moon -- sometimes called the Rose Moon or
Flower Moon -- is opposite the Sun, and the Sun is at its highest,
the full Moon will be at its lowest of the year just to the west of
the winter solstice in Sagittarius. From mid-northern latitudes,
the low lunar altitude commonly gives the Moon a ruddy look.
The ancient planets are all still rather inaccessible, though at
least Jupiter and Saturn are both rising before morning twilight.
Mars and Venus are too close to the Sun to be seen, and Mercury has
now passed its best and is quickly descending into evening
twilight. Only Uranus and Neptune are readily visible, the two
planets now rising in Capricornus before midnight. The Moon will
pass a degree south of Neptune (the fainter and western of the two)
around midnight the night of Monday, the 19th, and will pass south
of Uranus the morning of Wednesday, the 21st.
The full Moon washes out the stars. Nevertheless, look for the
bright star Antares in Scorpius a bit down and to the right of the
full Moon (flanked by its two outlying stars) and for the stinger
of the Scorpion directly below the full Moon. At the same time,
the Big Dipper is going over the pole, overhead for those in high
latitudes, well to the north for those in the south.
