Northern Sky by Deane Morrison
June 19 – July 2, 2021
Summer is officially settling in. The summer solstice arrives at 10:52 p.m. on Sunday, June 20. At this time, the sun reaches a point above the Tropic of Cancer and completes its annual northward journey. Then he reverses and starts heading south again. Slowly. When the sun is near a solstice, it is moving at glacial speed. It looks like the sun is at its maximum height, and the days are about as long as they are, for two months centered around the summer solstice. In fact, the word “solstice” comes from the Latin for “still sun”. On this day, the Earth will be illuminated from the Antarctic Circle to the North Pole and beyond to the Arctic Circle on the night side of Earth.
On June 24, we get the last of this year’s three super moons. This moon rises at 9:33 p.m., about eight hours after the moment of fullness. It might not look perfectly round, but it will be close to Earth and quite bright. He walks the night sky in Sagittarius, sitting right at the junction of the lid and handle of the Sagittarius Teapot.
On July 2, Earth reaches aphelion, its furthest distance from the sun. The Earth orbits slower when it’s farther from the sun, which means as I speak we are slowing down.
At this time of year, the stars and planets have barely six hours to strut. Venus gets a lot less; it shines through the afterglow of the sun, very low in the west-northwest, for barely an hour before going down. In the east, Saturn, then Jupiter, rise around midnight. Saturn is in Capricorn, the sea goat, and Jupiter has moved into Aquarius, the water carrier.
As night falls you will see a bright star high from south to southwest. Here is Arcturus, the brightest star in the kite-shaped constellation Bootes, the Shepherd. Below Arcturus we have Spica, the only reasonably bright star of Virgo, the Maiden. Low in the south is the S-shaped body of Scorpius. Its most salient feature is Antares, a gigantic red star at the heart of the scorpion. Just east of Scorpius is the Sagittarius Teapot.
Finally, a recent article in Astronomy magazine reminded me of a story I heard a long time ago. A reporter was covering a meeting of astronomers – where, I don’t remember – but there was, as usual, a room where many graduate students stood in front of posters of their research. The reporter saw one that had a small table next to him, and on it was a jar of dill pickles. So the reporter asked, what do dill pickles have to do with astronomy? And the graduate student explained that the vinegar in the pickle brine was based on acetic acid, and his group had detected acetic acid in space. Well, now many organic molecules have been detected in space including amino acids, the building blocks of proteins and DNA precursors. And Astronomy magazine just reported that scientists have found another one.
Ethanolamine, an essential component of the membranes that surround our cells, was found in a cloud of gas and dust just 390 light years from the center of the Milky Way.
This begs the question of how life came to be on Earth and possibly elsewhere. Has life been seeded from space? Sown in the form of essential molecules synthesized in space, some of which like ethanolamine, which could have assembled into membranes encapsulating and protecting the other essential molecules by forming small protocells? I will step forward and say that this issue will not be resolved any time soon.
Public views of the University of Minnesota night sky on its Duluth and Twin Cities campuses have been curtailed due to the COVID-19 pandemic. For more information see:
Duluth, Marshall W. Alworth Planetarium: www.d.umn.edu/
Twin Cities, Minnesota Institute for Astrophysics: www.astro.umn.
Discover astronomy programs, free telescope events, and planetarium shows at
Bell Museum of the University of Minnesota: www.bellmuseum.umn.
Find U of M astronomers and links to the world of astronomy at: http://www.astro.umn.edu