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Astronomy Fact of the Day

Fun astronomy facts to impress your friends with! 

Astronomy Fact of the Day for May 2017. 

Check back next month for more astronomy facts!

1st –Looking to the west around 10 o’clock tonight you will see the waxing crescent moon. The Moon is about 2,000 miles wide in diameter or about ¼ the size of Earth.

2nd – Looking to the east around 9 o’clock tonight and you will see the orange star Arcturus. This star is about 25 times the diameter of our Sun or about 20,000,000 miles in diameter!

3rd – Looking high in the southwest around 10 o’clock tonight you will see a group of stars that look like a backwards question mark. These stars form the head of Leo the Lion!

4th –Looking to the northeast around midnight you will see the summer triangle. Kepler 16b is a planet found in this area. It is like Luke Skywalker’s planet because it orbits 2 stars. May the 4th be with you!

5th – Public telescope viewing will be held at the James S. McDonnell Planetarium tonight with the St. Louis Astronomical Society. Click here for more information. 

6th – Looking to the southeast around 9 o’clock tonight you will see the Moon above Jupiter. Jupiter is about 88,000 miles in diameter. You could fit about 44 moons across Jupiter!

7th – On this date in 1992, Space Shuttle Endeavour lifted off on its maiden voyage into space. Endeavour is now retired and on display at the California Science Center.

8th –On August 21st this year the St. Louis area will experience a total solar eclipse. A solar eclipse will occur near the boot heel of Missouri in 2024.

9th –Looking to the southeast around 9 o’clock tonight you will see the gibbous moon above the star Zubenelgenubi. This star is part of the constellation Libra the Scales.

10th – Looking to the southeast around 9 o’clock tonight you will see the Moon. Tonight’s full moon is called the Full Flower Moon because at this time of year flowers are in full bloom.

11th –Looking to the southwest around 5 o’clock tomorrow morning you will see the waning gibbous moon above the red star Antares. This star is an M1supergiant larger than the Sun!

12th –Looking to the southwest around 5 o’clock tomorrow morning you will see Saturn to the left of the Moon. Saturn is about 72, 000 miles wide in diameter!

13th – Looking to the southeast around 9 o’clock tonight you will see a group of stars that look like a rectangle. This is the spring constellation Virgo the Maiden.

14th – Looking to the northwest around 11 o’clock tonight you will see the Big Dipper. The Big Dipper is part of the constellation Ursa Major the Great Bear.

15th –The next total solar eclipse visible in the St. Louis area will not occur until 2505! To learn more about the August 21, 2017 total solar eclipse and how to safely watch it visit https://eclipse2017.nasa.gov/

16th – Looking near the center of the sky around midnight tonight you will see a group of stars that look like a kite. This is the constellation Bootes the Herdsman.

17th –Pluto has a diameter of about 1,430 miles making it smaller than Earth’s moon!

18th – Looking to the northwest around 10 o’clock tonight you will see the bright star Pollux. If you look to the right of this star you will see its twin star Castor.

19th – The reason the Moon and Sun appear similar in size is the fact that the Sun is 400 times larger than the Moon but it is also 400 times farther from Earth.

20th – Get ready for the August 21st total solar eclipse at the Saint Louis Science Center’s Solar Saturday today or visit https://eclipse2017.nasa.gov/ on the web.

21st – Looking to the east around 5 o’clock tomorrow morning you will see Venus to the left of the crescent moon. Venus is about 7,500 miles in diameter which is about 500 miles smaller than Earth!

22nd –Looking to the northeast around 5 o’clock in the morning you will see Mercury to the left of the Moon on the horizon. This planet is slightly larger than the Moon with a diameter that is about 3,000 miles wide.

23rd –Because the Sun and Moon have the same apparent size total solar eclipses can occur as viewed from the Earth. To learn how to safely watch the August 21 total solar eclipse visit https://eclipse2017.nasa.gov/

24th – On this date in 1962, Scott Carpenter flew aboard Aurora 7 becoming the 2nd American to orbit the Earth. He completed 3 orbits and reached an altitude of 164 miles.

25th –Neptune has a diameter of 30,598 miles. This world is large enough to fit about 4 Earth’s across its diameter!

26th – On this date in 1951 Sally Ride was born in Los Angeles California. She was the first American woman astronaut and served as mission specialist aboard the space shuttle Challenger.

27th – Mars has 2 moons named Phobos and Deimos which means fear and terror. Both moons are smaller than the Earth’s moon. Phobos is about 14 miles wide and Deimos is about 8 miles wide.

28th – Solar eclipses can occur on other planets. The Curiosity rover saw the moon Phobos cross in front of the sun on August 20, 2013.

29th –The size of comet Halley is 10 miles by 5 miles by 5 miles! This comet passes Earth about every 76 years!

30th – The stars tell us summer is almost here! Looking to the east around midnight you will see the bright stars of the summer triangle. You will see these stars earlier in the evening during summer.

31st – Looking to the west around 10 o’clock tonight you will see the star Regulus to the right of the crescent moon. This star has a diameter about 4 times larger than our Sun!