Inside This Issue APR 2015 What's up in April

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Inside This Issue APR 2015 What's up in April Page 1 Skylights Newsletter of the Astronomical Society of Northern New England What’s Up In April hundred stars about 130 lights years away By Bernie Reim and about 600 million years old, or 8 times younger than our sun, and then the orange gi- he month of April is named for ant star called Aldebaran, which marks the aprilis, which means opening. That fiery eye of Taurus the Bull. This orange, is what part of the northern spectral type K5 star is about 65 light years hemisphere of the earth is starting away, twice as close as the Hyades that is to do this month. Our hemisphere seems to belong to, and fully 40 times the di- has now tilted more towards the sun as the days ameter of our sun. If you could place Alde- APR 2015 will continue to get longer and longer until the baran in our own sky, it would cover 20 de- summer solstice. grees, or two fists at arm’s length, and it would almost include the orbit of Mercury. There are many interesting highlights to Aldebaran means follower in Arabic, since it enjoy this month as our long, cold, and snowy seems to be following the Pleaides, and it is winter finally begins to soften its grip on us and one of the four royal stars of ancient Persia. our part of the earth begins to reawaken once The other three are Regulus, Antares, and Member of NASA’s again in its endless cycles. There will be nice Fomalhaut. They are all equally impressive conjunctions of the moon with Venus, and then and entirely unique. The first exoplanet di- with Jupiter, a Mercury and Mars conjunction, rectly visible in telescopes was discovered Venus giving us a grand tour of the constellation around Fomalhaut 7 years ago. of Taurus, the Lyrid Meteor Shower, and a total lunar eclipse. The Hyades star cluster is actually related to the Beehive cluster in Cancer, also known That is quite a full month of exciting as M44. The motions of the stars in these two highlights, but every month has unique clusters can be traced back to a common ori- happenings that will never happen exactly the gin in the sky, almost like tracing individual Astronomical League same way again. There are certainly patterns to meteors back to one point during a shower, observe, like the moon passing fairly close to called the radiant. They have other factors in each of the planets each month because they are common, like age, metallicity (heavier ele- ASNNE MISSION all on the same path though the sky, called the ments present) ecliptic, and all the meteor showers occurring at ASNNE is an the same time each year, and the saros cycles of “ Continued on page 2 ” incorporated, non- similar characteristics of lunar and solar profit, scientific and eclipses, but each individual event is always Inside This Issue educational organization with different and very interesting to watch, enjoy, three primary goals: and understand. Club Contact List pg 2 Brilliant Venus continues to brighten in our 1) To have fun sky as it catches up with Earth in its faster orbit Moon Data pg 3 sharing our around the sun. It will start this month 78% Sky Object Of The Month knowledge and illuminated by the sun, but it will be only 68% interest with others. NASA’s Space Place pg 4 illuminated by the end of April. As our sister planet travels through Taurus this month, Club Items For Sale 2) To provide basic climbing a little higher each evening, it will Meteor Showers in 2015 education in astronomy and nicely draw attention to some interesting related sciences to features and lead you on an educational and The Cold Never Bothered Me pg 5 all who are enlightening tour of this familiar constellation. Anyway interested. It will start with the Pleiades, also known as the Magnetically Levitating Black Holes pg 6,7 seven sisters or Subaru in Japanese, an open 3) To promote the cluster of about 500 stars located about 400 light Club Meeting & Star Party Dates pg 8 science of years away and about 100 million years old, Directions ASNNE Locations Astronomy. then the Hyades, and open cluster of about 200 Become a Member pg 9 Page 2 Skylights What’s Up “ Continued from page 1 ” also missed the total solar eclipse that hap- pened just a few hours before spring started. Club Contacts and proper motion through our galaxy. The It occurred at a super moon and was very Hyades form a giant oblate spheroid in space, spectacular over the Faroe and Svalbard Is- Officers: similar to the shape of the earth, most of lands, located halfway between Norway and President: which fits into a diameter of about 20 light the North Pole. years across. Ron Burk April 4. Full moon is at 8:05 a.m. EDT. This [email protected] As a nice bonus, the slender waxing cres- is also called the Grass, Egg, Pink, or Fish cent moon will also travel through Taurus, al- Moon. The total lunar eclipse will happen to- Vice President: beit at a much quicker pace, from the 19 th day just before sunrise. through the 22 nd , which is also Earth Day. Joan Chamberlin April 8. Saturn will be close to the waning [email protected] Notice that Mars and Mercury will form a gibbous moon this morning. close conjunction very low in the western sky Secretary: during that time 45 minutes after sunset. April 10 to 12. Venus will be close to the Carl Gurtman Pleiades in Taurus. [email protected] Jupiter will end its retrograde motion to- th wards the Beehive on April 8 , stopping five April 11. Halley’s Comet was closest to Earth Treasurer: degrees short of this relative of the Hyades on this day in 1986. Last quarter moon is at Ian Durham cluster. Then the King of the planets will re- 11:44 pm. sume its normal eastward or prograde motion [email protected] April 12. Yuri Gagarin became the first hu- in relation to the fixed background of stars for man in space on this day in 1961. the next 8 months, heading back into Leo. Be Board of Directors: April 16. Wilbur Wright was born on this day aware that Jupiter is heading for a great con- st in 1867. It was only 66 years after the Wright Nan Musgrave junction with Venus on July 1 . Brother’s made their first very tentative pow- [email protected] Saturn continues to rise a little earlier ered flight in 1903 that we traveled all the each evening and it will be rising by 9:30 by way to the moon. Tim Brown the end of April. It will reach opposition on [email protected] May 22 nd when it will rise exactly at sunset. April 18. New moon is today at 2:57 p.m. Notice that the ringed planet is already in ret- April 19. Mercury and Mars are visible close Sara Carter rograde motion, having ended its direct mo- together low on the western evening horizon. [email protected] tion on March 14, which was also the once in You may need binoculars to see them. a century Pi day when the date and time re- Star Party flects the first 10 digits of this irrational num- April 20. The slender waxing crescent moon joins Venus by the Pleiades this evening. Co-ordinator: ber, and Albert Einstein’s birthday. The Lyrid meteor shower peaks on the April 22. The Lyrid Meteor Shower peaks to- TBD nd night. morning of Wednesday the 22 . Caused by Comet Thatcher, which only orbits the sun Skylights Editor: April 23. Max Planck was born on this day in once every 415 years, this shower is not usu- 1858. He was one of the founders of quantum Paul Kursewicz ally too spectacular, only producing about 20 mechanics that completely redefines what [email protected] meteors per hour under good conditions. really happens at the very small scale of the However, there are always exceptions and universe. The shortest distance in the known Website Manager: any reason is a good one for getting out under universe is called the Planck length, which is the stars to enjoy and try to understand their 10 to the minus 35 meters. The shortest Jim Hatch vast beauty and power. amount of time, 10 to the minus 43 rd second, [email protected] The third total lunar eclipse of this very is called the Planck time. That is the time it NASA Night Sky rare tetrad of four total lunar eclipses that also takes light to travel the width of a proton. Network fall on important Jewish holidays will happen That is also as far back as any humans can Co-ordinator: on Saturday morning, April 4 th . This is only possibly see after the instant on the Big Bang. the eighth such tetrad in the past 2,000 years. April 24. On this day in 1970 China becomes Joan Chamberlin We are not well placed here on the East coast the 5 th nation to launch a satellite. [email protected] to see much of this rare event, but we can April 25. The Hubble Space Telescope was catch a little of it just before the moon sets in JPL Solar System deployed on this day in 1990. First quarter the morning as the sun rises. It will only have Ambassador: moon is at 7:55 p.m. EDT. Joan Chamberlin entered the penumbral shadow at that point, [email protected] so you will need binoculars to discern any April 30.
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