Astronomy news for the two weeks starting Friday, March 11, 2016.
The next skylights will appear March 25. Daylight Savings Time
begins on Sunday the 13th.
The Moon first grows in its pretty waxing
crescent phase as it approaches first
quarter on Tuesday, March 15, the famed "Ides of March,"
following which it glides through the waxing gibbous, which ends at full Moon on Wednesday the 23rd about the
time of Moonset in North America, when the Moon will also undergo
a penumbral eclipse. But don't bother watching as
the Moon will just barely hit the partial shadow of the Earth and
be just slightly dimmed, none of it ever immersed in total shadow.
We finish with just a couple days of the waning gibbous as our two-week period runs out.
Starting just after perigee, where
the Moon is closest to Earth, our satellite gradually works its
way through the fortnight to apogee on Friday the 25th, where it
is farthest from us (the change in distance not readily
noticeable).
The night of Sunday the 13th finds the Moon to the west of Aldebaran and the Hyades in Taurus, while the following evening it will be east of
the star and cluster. Then from the night of Saturday the 19th to Tuesday
the 22nd, watch the Moon run south of Leo. The evening of the 19th it will be west of Regulus, the following night to the
east of the star. The near-full Moon will then pass just two degrees
south of Jupiter the
evening of Monday the 21st.
Jupiter rules the night, the planet glimmering brightly as evening
twilight descends. It now transits the meridian to the south shortly before
midnight and does not set until after sunrise. Still in retrograde
(moving east against the stars), as noted above it shines to the
south of classical Leo to the southeast of Regulus. As Jupiter
transits, Mars
rises. On the morning of Wednesday the 16th the red planet will
pass just barely (a mere nine minutes of arc) north of the bright
star Graffias, Beta Scorpii,
one of the prominent stars that make the head of Scorpius. An hour after Mars rises,
Saturn
vaults over the horizon. On Friday the 25th, Saturn also enters
retrograde as the Earth prepares to pass between it and the Sun,
the ringed planet, Mars, and Antares making a fine triangle. The
similarity in color between Mars and the star gave the latter its
Greek name, name "Ant-Ares," "like Mars." In the morning, Venus
rises in mid-dawn. The brilliant planet passes a mere half a
degree south of Neptune on
Sunday the 20th, the event quite invisible because of the
brightening sky. Finally, Mercury is in superior conjunction with the Sun (on the
other side of it) on Wednesday the 23rd.
Well, not quite finally, as the Sun passes the vernal equinox in Pisces
at 11:30 PM CDT on Sunday the 20th (12:30 AM EDT on the 21st, 9:30
PDT on the 20th), marking the beginning of spring in the northern
hemisphere (and the beginning of autumn in the southern). Given
the midnight passage, on Sunday the 20th and Monday the 21st, the
Sun will closely rise due east, set due west, and days and nights
will be of equal length. The Sun also rises at the north
pole and sets at the south
pole.
As Canis Major with Sirius (the sky's brightest star)
scoots off to the west, it is for a bit replaced in the south by
the northern stars of Puppis, the
stern of Argo the Ship. Farther
south is the second brightest star of the sky, Canopus (in Carina, the Ship's Keel), which is visible only from
the far southern US (Florida, Hawaii, Arizona, etc.).
