Contact: Barbara Anthony-Twarog, (785) 864-3910 or anthony@kubarb.phsx.ku.edu Star Log is reprinted with permission from the newsletter of the Astronomy Associates of Lawrence. Readers may send astronomy questions to AAlice, c/o Dept. of Physics and Astronomy, The University of Kansas, Lawrence, KS 66045. For a free star chart, enclose an SASE.
1. The moon will be at first quarter phase at 11:27 a.m., not the best time to see a waxing moon. The moon should clear the eastern horizon at about 2 p.m., but you'll need to wait until evening to admire the background stars of Ophiuchus.
5. Astronomers use the term zenith to describe the point directly overhead. As the Earth's motion carries stars from east to west, some objects pass directly through the zenith. If a person in eastern Kansas looks straight up this evening at about 9 p.m., the bright blue star, Vega, will be very near the zenith. In just two weeks, Vega will be at the zenith at 8 p.m., just barely visible in the waning twilight.
7. Jupiter is very close to a gloriously bright star in Taurus today, mellow Aldebaran. Jupiter has been pretty glorious itself these past weeks, moving with Taurus hours ahead of the sun. If you rise before 6 a.m. (about an hour ahead of sunrise), Jupiter will be a little south of the zenith.
10. The moon is approaching full phase and will march this evening through the zodiac constellation Capricornus. It's easy to see how these dozen constellations have received so much attention over the millenia, since the moon, sun and all the planets have paths passing through them. If you find the waxing moon this evening, Uranus will be three lunar diameters north of it, probably too faint for you to see without a telescope.
12. What do you think about when you look at the moon? Astronomers have been known to grumble about the moon; it has even been suggested that the moon should be painted a darker black, so that it would reflect less sunlight. (This wouldn't help much, as it happens - the moon is already very non-reflective). Here's something to think about this evening -- just 41 years ago today the very first object sent by Earth's technology struck the moon, the Soviet spacecraft Luna 2.
13. Each full moon throughout the year appears in front of a different section of the zodiac. Tonight, Capricornus and Aquarius share the honor of hosting the harvest moon. The full moon for each month has a traditional name, with this full moon nearest the autumn equinox being the most famous. The harvest moon reaches its phase at 2:37 p.m. today.
17. September 1789 was a tumultuous time in the world. The Bill of Rights was ratified that month, changing the course of the young United States. A month before, revolutionaries in France had crafted the Declaration of the Rights of Man and the Citizen. In England, astronomer William Herschel continued his work. On this date in 1789, he discovered the Saturnian moon, Mimas.
19. How many reasons are enough to get you out of bed before sunrise in the morning? If three good reasons are enough, this may be the day for you to check the sky at 6 a.m., about an hour ahead of the sun. High above the southern horizon stands the moon in Taurus, flanked by Saturn on the right and Jupiter on the left.
20. The moon will reach its last quarter phase at 8:28 p.m., but it will be after midnight before the moon rises. You can look eastward after midnight, or better yet, wait until about 5:30 or 6 a.m. tomorrow; look to the south, where you'll see the half-lit moon to the left of Jupiter and Saturn.
22. There are two times each year when the sun's path crosses the invisible extension of Earth's equator. These events, and the position of the sun for each event, are called the equinoxes because the hours of day and night are roughly equal. The autumnal equinox is scheduled for 12:27 p.m.
23. In the 154 years since its discovery on this date in 1846, Neptune has moved the width of a constellation. Berlin astronomers Johann Galle and Heinrich d'Arrest had the advantages of their observatory's refractor telescope, new and excellent charts, and the mathematical predictions of Urbain Leverrier. English astronomer John Couch Adams had made very similar predictions. This was the first deliberate sighting of Neptune; it turned out that the eighth planet had been seen a number of recorded times in the 18th and 19th centuries, but was always mistaken for a star.
24. Today, the moon is as close as it will be all month, a mere 228,000 miles away from Earth's center. Thirty years ago today, a Soviet spacecraft, Luna 16, engineered the first unmanned return of lunar material to Earth.
25. If you're willing to rise before the sun one more time, the eastern horizon at 6 a.m. will offer a lovely view of the very slim crescent moon, the planet Mars, and the brightest star of the constellation Leo, lovely Regulus. Leo is one of the more recognizable constellations, shaped like a question mark. Regulus forms the period of the question mark. Mars is actually a good bit fainter than Regulus.
27. If we could only see the background stars through the glare of the sun. Not only would we understand the motion of the sun and planets with greater clarity, we'd see the moon's position today as it blocks some stars in Virgo. The moon is a couple of degrees north of the sun as it passes new phase at 2:53 p.m.
29. The moon is quite young this evening, but the nearly new moon is always a beautiful sight at twilight. One of the prettiest sights in the sky is called "the new moon in the old moon's arms." In addition to the sunlit sliver of the crescent moon, the rest of the Earth-facing side can sometimes be seen by reflected Earthlight. As an added bonus, Venus is nearby. The best time to scan the western horizon is near 7:30 p.m.
30. Henry Draper was quite a bit more than a well-to-do physician from 19th-century Boston. He was an avid amateur astronomer, maker of one of the largest telescopes in the world. On this date in 1880, he took the first astronomical photograph of a nebula, the Orion Nebula. Draper must have had a very long night - in late September, Orion rises well after midnight.