November 19, 1999
Contact: Barbara Anthony-Twarog, (785) 864-3910.
1. Some of the best sights in the universe will brighten these long, cold nights. Mercury (in Libra) and Venus (in Virgo) are sharing the pre-dawn sky while Jupiter and Saturn share the evening sky with Mars. Mars sets, with the constellation Capricornus and faint companions Neptune and Uranus, before 9 p.m.
2. The plane of the solar system is easy to trace these early December mornings as the planets' projected positions outline the ecliptic. These "pointers" will be especially helpful if you would like to find Mercury, normally a tricky planet to observe. Mercury will be at a fairly favorable position for viewing tomorrow morning before sunrise (the sun comes up at about 7:30 in eastern Kansas). The waning moon is high above the east-southeast horizon, with Venus about 15 degrees nearer the horizon. If you extend the line joining the moon and Venus, you'll find Mercury even closer to the horizon. The distance between Venus and Mercury is about 1.5 times the moon-Venus separation.
3. How badly we need a feast of light at this time of year! One important winter religious festival begins at sundown this evening, the celebration of Hanukkah. The sun's position on the celestial sphere (really, really far south) and the latitude of Kansas determine a sunset time that is a little before 5 p.m.
7. By the time the moon is closest to the sun's position in the sky (at 4:32 p.m.), both will be heading for the western horizon. The sun's glare effectively drowns out the stars of Scorpius behind it but that's not the reason why the moon is invisible today; the sunlight side of the moon is facing away from Earth at new moon phase.
11. Today is the 136th anniversary of the birth of a remarkable woman astronomer, Annie Jump Cannon. Born in Dover, Del., Cannon initiated her career at the Harvard College Observatory when she was in her early 30s. One of the great efforts of the observatory at that time was the publication of a catalog of over 300,000 stars with spectral classification, a basic description of a star's intrinsic properties. Over the next 25 years, Cannon became the chief classifier of stellar spectra >from photographic plates and the curator of Harvard's impressive collection of photographic plates.
15. At first quarter phase at 6:50 p.m., the moon is bright enough to outshine some pretty bright competition. Brilliant Jupiter is still commanding attention in the evening sky. Look for it east of the moon (to the moon's left as you face south). Saturn is even further east and not nearly as bright.
17. Have you heard of the Guzman Prize? If not, it may be because it has never been awarded. This prize of 100,000 francs was offered on this date in 1900 to anyone who could prove by communication the existence of any extraterrestrial beings. Because everyone expected Mars to hold life, communication with Martians was considered too easy and was excluded.
19. Jupiter has been so brilliant these past months that Saturn might be overlooked but what a waste that would be. Not the brightest - but arguably the most beautiful - planet to see in a telescope, Saturn is at least as bright as any of its stellar neighbors in the constellation Aries. Saturn culminates (is at its highest point above the southern horizon) just before 10 p.m.
20. Each of the outer planets (Mars, Jupiter and Saturn are the brighter ones) has a point in its orbit as seen from Earth when it appears to stop, backpedal westward against the stellar background, and then resume its normal eastward progress. Jupiter is at that second stationary point tomorrow, marking the end of the period surrounding its "opposition" when it is above the horizon all night. Now in Pisces, Jupiter will move over the next year through Aries and on into Taurus.
21. The sun reaches its "stand-still" point, or solstice, at 1:44 a.m. tomorrow, as far south as it will be this year. This is our longest night and from today, the days will slowly lengthen.
22. The moon is full phase at 11:31 a.m., a time when the moon is about as far below the Kansas horizon as it can be. One of the features of full moon phase is that the moon is very nearly opposite the sun's position in the sky. At midnight, the moon will be in approximately the same position as the sun is at noon, with one critical difference - as the sun is nearly as far south as it can be, the full moon will be the most northerly of the year. Near midnight, the full moon should be just 20 degrees from the zenith, the point directly overhead.
24. Although unmanned spacecraft had photographed the far side of the moon before 1968, it was on this date of that year that the crew of Apollo 8 became the first humans to see that landscape for themselves. One of the most wonderful holiday gifts that they were able to present to the world was a view of our beautiful planet as it appeared from another world.
25. People are very touchy about time and calendar issues; witness the degree of concern over the upcoming turnover of our millennium clock. But imagine having the date of your birthday moved. Isaac Newton, perhaps one of the greatest scientists of this millennium, was born on Dec. 25, 1642, Christmas Day of that year. Although the calendar had been brought into line with the seasons by the Gregorian calendar reforms of 1582, Britain did not adopt the "new style" dates until 1752 because the reforms were so associated with the Catholic Church. From that point, the anniversary of Newton's birth was reckoned from Jan. 4, 1643. Newton had died in 1727.
29. We tend to forget that the moon is above the horizon in daylight hours for some part of most days. Look for the moon at 8:04 a.m. when it reaches last quarter phase. The moon is in Virgo, but these distant stars faded into the bright sky when the sun rose. Besides being above the horizon between midnight and noon, the last quarter moon is sunlit on the left-hand (eastern) side.
31. Astronomers are not terribly diverted by Y2K concerns, perhaps because they know a great deal about calendars and time keeping. Some measures of time are fixed by nature - the average length of a day, the length of a year, the date on which the first day of spring is most easily reckoned. Everything else - hours, minutes, months, weeks, centuries and decades - are relics of human choice, as arbitrary and charming as such choices may be. So, whatever else people may look forward to with concern or excitement, rest assured that the heavens are immune from our little bug.