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MAR 2018 What's up in March Inside This Issue Page 1 Skylights Newsletter of the Astronomical Society of Northern New England will be 90% lit at the beginning of March and What’s Up in March down to just a few percent as it disappears By Bernie Reim again towards the end of the month. Even without a telescope or binoculars he month of March is named for you will notice that Venus is about 8 times Mars, the Roman god of war, but it brighter than our first planet as March be- is also known as the guardian of gins, but then Venus will be fully 100 times agriculture and as an ancestor of the brighter than Mercury by the time it disap- MAR 2018 Roman people. March was also the pears again around the time that spring starts first month of the year on the early Roman on the 20 th . Watch for 3 nights in a row as a calendar. slender waxing crescent moon joins the pair th For us in the northern hemisphere, March of our first two planets from the 18 to the th always marks the beginning of spring. This year 20 . th that will happen on Tuesday the 20 at 12:15 Many people have never seen Mercury p.m. The vernal equinox is further defined as the since it always stays close to the sun and Member of NASA’s sun on the ecliptic crossing over the celestial therefor never gets very high in our sky. Now equator on an upward path, also called an is your chance. Mercury is a strange planet ascending node. This will be one of only two without any moons that orbits the sun very days each year that the sun will rise due east and fast at 30 miles per second every 88 days and set due west for everyone on Earth, except for takes 59 days just to rotate once on its axis. the poles. The days will also be 12 hours long That is a 3 to 2 ratio. It is also very dark and for everyone on Earth within a few days of that reflects even less sunlight than the moon, date, except for the poles. which only reflects about 8% of the sunlight There will be some warmer days and nights that hits it back into space, absorbing the re- Astronomical League now that spring will have arrived, so it is time to maining 92%. The earth reflects just over get outside more often to look up and enjoy the night sky and some of its myriad phenomena. “ Continued on page 2 ” ASNNE MISSION The highlights for this month include a great conjunction of Venus and Mercury in the Inside This Issue ASNNE is an evening sky, a close conjunction of Mars and incorporated, non- Saturn in the morning sky, several nice Club Contact List pg 2 profit, scientific and conjunctions of various phases of the moon with educational Moon Data pg 3,4 organization with various planets, and Mercury’s best evening Sky Object Of The Month three primary goals: appearance of the year. This month starts out with Venus and 1) To have fun Mercury less than 2 degrees apart low in the RED ALERT: LASERS IN SPACE pg 5 sharing our western evening sky just 20 minutes after sunset Meteor Showers in 2018 knowledge and interest with others. in the constellation of Pisces the Fish. On NASA’s Space Place rd Saturday evening the 3 , brilliant Venus will be just 1.1 degrees to the left of Mercury. That can What Is the Ionosphere? pg 6,7 2) To provide basic education in be measured by holding up one finger at arm’s astronomy and length. They will still be very close the next Astroimaging pg 8 related sciences to evening, but Mercury will be a little above all who are Venus by then. Club Meeting & Star Party Dates Pg 9 interested. Directions ASNNE Locations Through a telescope you will see that Venus 3) To promote the is 97% full at the beginning of March, but that it Become a Member pg 10 science of is getting less illuminated by the sun as it gets Astronomy. closer to us again. Mercury also goes through phases like the moon for the same reason, but it Page 2 Skylights What’s Up “ Continued from page 1 ” good photo opportunity. Club Contacts one third of sunlight back into space and ab- sorbs under two thirds. March 1. Full moon is at 7:52 a.m. EST. This is also called the Worm, Crow, Sap, or Lenten moon. Officers: Named for the Roman god of commerce March 2. Notice that the moon, Jupiter, Mars, and and thieves, Mercury is named for Hermes in President: then Saturn are nicely spaced in a giant in celestial the Greek mythology, who was the swift one arc on the ecliptic in the morning sky. Ron Burk or the messenger. Since Mercury has no at- [email protected] mosphere and is so close to the sun, it has the March 3. Venus and Mercury are only one degree widest temperature range of any planet in the apart low in the western evening sky right after sunset in Pisces. Vice President: solar system. It will reach over 800 degrees F Joan Chamberlin on the sun side and drop down to minus 300 March 5. The zodiacal light might be visible for a [email protected] on the night side every day, a difference of couple more weeks low in the western sky about 1100 degrees. 90 minutes after sunset. Challenge yourself to find Secretary: this tall, hazy pyramid of subtle light caused by re- Carl Gurtman The last mission we sent there was appropri- flected sunlight off comet dust and debris forming [email protected] ately called Messenger and it solved some a torus all along the ecliptic plane of our solar sys- mysteries but raised many more about this tem. I have seen it twice. Treasurer: enigmatic first planet. Mercury has a very March 7. Jupiter and the waning gibbous moon are Ian Durham heavy metal core that is 60% of its mass, less than 4 degrees apart just before midnight as [email protected] twice that of any of the other terrestrial plan- they both rise together. ets. March 9. Last quarter moon is at 6: 21 a.m. Board of Directors: Jupiter has just switched into an evening March 11. Daylight-saving time starts at 2 a.m. planet as March begins, and it will be rising March 13. Sir William Herschel discovered the Gary Asperschlager an hour earlier by the end of March. The king [email protected] planet Uranus on this day in 1781. He first named of the planets is in Libra the Scales now and it George in honor of the king, but it was soon re- Larry Burkett continues to get a little higher and brighter named after the Greek father of the Titans, whose [email protected] each night as it gets closer to us approaching name also means “the heavens.” This planet will its opposition on May 6, when it will rise at be about 4 degrees above and to the right of Venus Chase Delaney sunset and remain in the sky all night long. on March 28, but the twilight will be too bright to [email protected] see it without a telescope or good pair of binocu- Jupiter will end its normal, direct, east- lars. th Star Party ward motion through our sky on March 9 , thereby beginning its 4-month-long retro- March 14. Albert Einstein was born on this day in Co-ordinator: 1879. He discovered general relativity in 1915, just grade loop, the midpoint of which is its oppo- over 100 years ago, but he could not develop a uni- TBD sition. Notice that you can see several of its fied field theory that links the world of the very large Galilean moons just in a pair of binocu- small, quantum mechanics with the world of the Skylights Editor: lars. very large. March 16. Caroline Herschel was born on this day Paul Kursewicz The remaining bright planets are still [email protected] morning planets this month. Mars begins the in 1750. She discovered 8 comets and worked month rising around 2 am and Saturn begins closely with her brother William throughout her career. They were also both accomplished musi- Website Manager: by rising at 3 am, but Mars catches up rapidly cians. and they both rise just after 1 am by the end Nan Musgrave of March in Sagittarius. They will be less March 17. New moon is at 9:13 a.m. EDT. [email protected] than 2 degrees apart by then, having started March 20. Spring starts at 12:15 p.m. EDT. the month 17 degrees apart. Notice that they NASA Night Sky both start at about the same brightness, but March 22. The moon is less than one degree from Aldebaran this evening, occulting it for parts of Network that Mars will get brighter much faster than this country. Co-ordinator: Saturn. It is still too early to discern any fea- tures on Mars in a small telescope, but be March 24. First quarter moon is at 11:36 a.m. Joan Chamberlin aware that Mars is getting closer and brighter March 29. Mars and Saturn are only 2 degrees [email protected] apart in the morning sky. Look for the globular every day and it will be at its best on July 29, which will be one of its closest oppositions in cluster M22 with about 100,000 stars about one JPL Solar System degree below the pair of planets.
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