Saturday: I hope that you have never been in a collision. It can be scary and dangerous. The biggest collision in our celestial neighborhood may occur in a few billion years when our Milky Way Galaxy may collide with the Andromeda Galaxy. Notice I said, “MAY occur” and “MAY collide. Up until about a year ago I would have sounded more certain. But recent simulations by astronomers have lowered the chance of a collision to about 50%. These new simulations did a better job in accounting for the effects of the smaller galaxies in the celestial neighborhood. This video shows a simulation with the new findings: https://youtu.be/o2x_31dE04s.
If you can’t stay awake for a few billion years to see the
possible collision, stay up until late at night to see the Andromeda Galaxy.
First find the Great Square of Pegasus. At 2:00 a.m., the left-hand corner of
the square is about two fists held upright and at arm’s length above the
east-northeastern horizon. Less than two fists to the left and down a little
bit is another star, the same brightness as the star at the corner of the
square. From that star, hop about a half a fist up to a star that is about one
fourth as bright. Less than another half fist in the same direction is a fuzzy
oval patch of light known as the Andromeda Galaxy. The galaxy is about two and
a half fists above the northeastern horizon. The galaxy is impressive to see in
binoculars. It consists of nearly a trillion stars and is 2.2 million light
years away.
Sunday: The Globe at Night June campaign starts tomorrow.
Globe at night is a citizen science project to quantify the impact of light
pollution on our view of the night sky. Go to https://globeatnight.org/campaigns/
to learn more and participate. This is a fun way to observe the night sky and
contribute to science at the same time.
Monday: Venus and Jupiter are neighbors in the sky all week
but tonight they are at their closest. Look for them one and a half fists above
the west-northwestern horizon at 9:45 p.m. Mercury is to the lower right of
them, less than a fist above the horizon.
Tuesday: Alkaid, the end of the Big Dipper handle, is nearly
straight overhead at 10:00 p.m.
Wednesday: In 1982, the British group Bow Wow Wow first
sang, “I Want Candy”. In May 2019, NASA finally granted that wish by releasing
images of Mars’ moon Phobos looking like candy. The thermal imaging camera on
NASA’s long lived Odyssey orbiter took a series of images of the full phase of
Phobos. The resulting composite, looking like a many layered jawbreakers, shows
how the temperature varies throughout the small moon. This temperature
distribution, in turn, can help astronomers determine what the moon is made of.
For more about this yummy treat, go to https://www.jpl.nasa.gov/news/why-this-martian-full-moon-looks-like-candy.
Mars is about half a fist above the east-northeastern horizon at 4:15 a.m.
Saturn is nearly two fists above the east-southeastern horizon at this time,
just to the lower right of the moon.
Thursday: It looks so peaceful up in the night sky. But the
sky is not peaceful for Jupiter. According to a recent study by astronomers,
Jupiter gets hit by a 5-20 meter diameter asteroid 10 to 65 times a year. For
comparison, the object that exploded over the Russian city of Chelyabinsk in
2013 was 20 meters in diameter. Earth gets hit by a 20-meter asteroid about
once every 50 years. Jupiter is one fist above the west-northwestern horizon at
10:00 p.m., right below the brighter Venus. You can see how much Venus has
moved compared to Jupiter over the past three days.
Friday: Are you up at 12:52 a.m., looking due north and
thinking you see a UFO coming to take you away? That's no UFO. It's the bright
star Capella, a circumpolar star that never goes below the horizon as viewed
from Ellensburg.
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.
