Saturday: This week is International Dark Sky Week. Lights that are aimed upwards or not properly capped illuminate the atmosphere and obscure dim objects. Having too much light shining where it shouldn’t is considered light pollution. And just like other forms of pollution, light pollution can be hazardous to our health and the health of other animals. That’s right. Harmful. Watch this National Geographic video for more information: https://youtu.be/V_A78zDBwYE. Learn about how you can help at https://idsw.darksky.org/.
Sunday: The first day of spring was March 20. The most
recent full moon was April 12. That means today is Easter. The standard way to figure
out the date of Easter for Western Christian churches is that it is the first
Sunday after the full moon that occurs on or after the vernal equinox, also
known as the first day of spring. Of course, the other standard way is to look
for the date of church services celebrating the resurrection of Jesus. There is
no Bible story of an “Easter star”. If there were, Spica would be a pretty good
choice. The name Spica comes from the Latin “spica virginis” which means
“Virgo’s ear of grain”. Spica represents life-giving sustenance rising after a
long winter just like the risen Jesus represents life-giving redemption to
Christians. Spica is two fists above due southeast horizon at 9:00 p.m. For an
algorithm on how to calculate the exact date of Easter for any year, go to https://www.rmg.co.uk/stories/topics/when-easter.
Monday: Mercury will be as far away from the Sun in the sky
as it will get this half of its orbital cycle. This "farthest away"
point is known as the planet's greatest elongation. Since Mercury is in the
morning sky, it is west of the Sun and this occurrence is called the greatest
western elongation. Often, the day of greatest elongation is a good time to
observe Mercury. But not this cycle. Mercury is just barely above due east at
5:30 a.m. You are much more likely to see the bright planet Venus, nearly a fist
held upright and at arm’s length above the eastern horizon. You should be able
to see Mercury with binoculars. Saturn may also be visible with binoculars,
about halfway between Venus and the horizon. Over the next few weeks, Mercury
will move toward the Sun in the sky. By mid June, it will be visible in the
evening sky.
The Lyrid meteor shower peaks tonight. The meteors appear to
come from a point to the right of the bright bluish star Vega in the
constellation Lyra the lyre. This point is about three fists above the
east-northeast horizon at midnight tonight. The best time to see the shower this
year is between 11:00 p.m. and moonrise at 4:00 a.m. Typically, this is one of
the least interesting major meteor showers of the year, with 10-20 bright, fast
meteors per hour. However, it is also one of the most unpredictable. As
recently as 1982, there were 90 meteors visible during a single hour. In
addition, the Lyrid meteor shower has historical interest because it was one of
the first ones observed. Chinese records say “stars fell like rain” in the
shower of 687 B.C. As your mother might say, dress warm and sit in a
comfortable chair for maximum enjoyment. Meteors are tiny rocks that hit the
Earth and burn up in the atmosphere. For more information, go to http://earthsky.org/?p=158735.
Tuesday: Jupiter is nearly three fists above due west at
9:00 p.m. Mars is nearly six fists above the southwestern horizon at this time.
Wednesday: Sirius, the brightest star in the night sky, is
getting lower and lower. It is one fist above the southwestern horizon at 9:00
p.m. By mid-May, it will be lost in the glare of the setting Sun.
Thursday: On Monday I described Venus as “the bright planet
Venus”. This morning, it is at its brightest for this orbital cycle. Its visual
magnitude is -4.54. By comparison, Jupiter, the second brightest point of light
in the sky, is magnitude -2, only about one tenth as bright. Venus is about a
fist above the eastern horizon at 5:30 a.m.
Friday: As the rock group Journey once thought of singing,
“Wheel in the sky keeps on turnin’. I know where the Dipper’ll be tomorrow.”
Every night, the Big Dipper and Cassiopeia make a wheel in the sky that turns
around the North Star in a counterclockwise direction. Every year on April 24
at 10:00 p.m., the Big Dipper is straight overhead and W-shaped Cassiopeia is
low on the northern horizon. Every year on April 25 at 10:00 p.m., the Big
Dipper is straight overhead and W-shaped Cassiopeia is low on the northern
horizon. Every year on April 26 at 10:00 p.m., the Big Dipper is straight
overhead and W-shaped Cassiopeia is low on the northern horizon. Oh, am I
boring you? Of course, there are subtle charges in the position from night to
night. Each northern constellation moves about one degree counterclockwise from
one night to the next. But this is not going to change their position in the
sky drastically over a few days. So, if you know where the Big Dipper is
tonight, you DO know where it’ll be tomorrow. If you are really struggling to
understand this concept, Don’t Stop Believin’ in yourself. Just keep studying
Faithfully.
The positional information in this column about stars and
planets is typically accurate for the entire week. For up-to-date information
about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.
All times are Pacific Time unless noted.
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