Saturday: Many artists have sung the song “Blue Moon”. But few have sung the song “Blue Planet”. It goes, in part “Blue Planet, you saw me standing with 28 others. Rolling around like a barrel. Without a worry or care-L.” It’s about the planet Uranus, which orbits the Sun in a rolling motion and has 28 moons. Every one of Uranus’ moons is named after characters in works by William Shakespeare or Alexander Pope. Uranus is relatively easy to find tonight and will get easier to find over the next two weeks. It is three fists held upright and at arm’s length above the western horizon at 8:00 p.m., easily visible with binoculars. First find Jupiter, a little more than two and a half fists above the western horizon. With Jupiter at the bottom of your field of view, Uranus will be at the top of your field of view. Return to this same spot for the next few nights. If the point you are looking at moves compared to the neighboring points of light, you are looking at Uranus. Over the next three weeks, Uranus and Jupiter will move towards each other in the evening sky.
Sunday: The first day of spring was March 19. The most
recent full moon was March 24. That means today is Easter. The standard way to
determine 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 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: Global Astronomy Month (GAM) starts this week. Go to
https://my.astronomerswithoutborders.org/programs/global-astronomy-month
for more information about events. If you want to take a chance on a spur of
the moment event, visit their Facebook page: https://www.facebook.com/astronomerswithoutborders/.
Tuesday: Within the next few months, astronomers think a new
star will form in the constellation Corona Borealis. This constellation is
about three fists above the eastern horizon at 11:00 p.m. The new star will
form just below the brighter curve-shaped line of stars that gives the
constellation its name.
Wait a minute. Stars take millions of years to form. This
must be some sort of April Fool’s joke.
No Joke. The star T Coronae Borealis, abbreviated T CrB, is
a two-star system in which a white dwarf and a red giant orbit a common center
of mass. For about 80 years, the white dwarf star pulls mass from the red
giant. When it pulls in a certain amount of matter, the matter ignites in a
chain reaction nuclear explosion that lasts for many Earth days. When this
happens, the normally very dim pair of stars get bright enough to be seen with
the naked eye. Based on the details cataloged by astronomers during previous
ignitions, as well as recent measurements, the next event should occur between
now and September. The general name for this type of “new star” is a nova.
By now you’ve learned that the star is not really new, just
newly, and temporarily, bright. This star will get higher in the sky earlier as
the weeks go by, making it easier to see. Memorize the shape of Corona Borealis
so you’ll notice when it is different. For more information about T CrB, go to https://www.scientificamerican.com/article/this-nova-will-soon-erupt-as-a-once-in-a-lifetime-new-star-in-the-night-sky/.
Wednesday: It is time to start getting ready for next
Monday’s total solar eclipse. Everyone in the lower 48 states in the USA will
be able to see at least a partial solar eclipse. Make sure you watch it safely.
The American Astronomical Society (AAS) and Big Kid Science have teamed up to
make a simple and useful app called Totality. It shows the path superimposed on
a USA map, provides the exact time of the event in your location, as well as a
model of the shadow path. Go to https://eclipse.aas.org/totality
for more information on how to download.
In addition, the AAS has a list of safe solar viewing
techniques and tools, including disco balls. Go to https://baas.aas.org/science-in-the-shadow-safe-ways-to-view-the-sun
for more safe solar tips. If you use these tips, your eyesight will be “Stayin’
Alive”.
Thursday: Last week you looked at something fuzzy, the Milky
Way. So, reward yourself tonight by looking at something sharp and detailed.
The OSIRIS-REx mission sent back the highest resolution global map of any Solar
System object, the asteroid Bennu. Using pictures taken from just three to five
kilometers above the surface, the map has a resolution of five centimeters per
pixel, the most detailed map of any object other than Earth. Go to https://www.asteroidmission.org/bennu_global_mosaic/
to download the map.
Friday: At 6:00 am tomorrow morning, the moon, Saturn, and
Mars line up diagonally from the eastern horizon.
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.