Skywatch Line for Monday and Tuesday, February 13th and 14th, 2017

This is the Skywatch Line for Monday and Tuesday, February 13th and 14th.

The Sun sets at 5:24 PM; night falls at 7:00. Dawn begins at 5:18 AM and ends with sunrise at 6:53.

The evening sky presents two bright planets and a dimmer one, all in Pisces. Venus is the brightest, at magnitude minus 4.6. It blazes in the southwestern sky and is moderately high. This month Venus becomes slightly brighter, but larger and slimmer in our telescopes. Today, it is about 30 percent illuminated; by month’s end, it will be about 18 percent lit. This the result of Venus closing in on Earth, and presenting a side view of its daylight face. Venus sets at 9:05 PM.

Mars is next brightest, at first magnitude about 6 degrees to Venus’ upper left. It appears tiny, compared to Venus, but its characteristic red color makes identification easy. Mars sets at 9:25 PM. Uranus shines at sixth magnitude, naked eye visible under dark skies. It appears about 9 degrees to Mars’ upper left. This blue-green world materializes as a tiny dot in binoculars or telescopes. Uranus sets at 10:10 PM.

Nightfall finds the 18-day-old Moon in Virgo. It is about 90 percent illuminated and blazes at eleventh magnitude; Tuesday, finds it thinner, dimmer and closer to Jupiter. The Moon rises at 8:27 PM Monday, and at 9:28 Tuesday. The Moon sets during daylight.

Asteroid 4Vesta inhabits Gemini. This tiny, sixth magnitude rock is a challenge object. It is found about one degree below the star Upsilon; a detailed star chart, from astronomy media, will aid the observer. Vesta is best observed at about 10 PM.

Jupiter rises about 10:10 PM. The giant planet still hovers above Virgo’s bright star Spica. Wednesday’s Moon is 3 degrees from Jupiter. Jupiter is best observed at 3:44 AM. Telescopic observers can see the Great Red Spot, a giant storm on Jupiter, at 11:01 PM on Monday, and at 4:48 AM on Wednesday. On Tuesday night, Jupiter’s moon Io begins to cross the planet’s face at 3:47 AM and Io itself begins its travel at 4:44 AM.

Saturn rises at 3:23 AM and, by Dawn, is high enough for observation. At 0.5 magnitude, it is easy to spot, low off the eastern horizon. But the rapidly brightening sky requires quick action for an observer to see the famous rings.
Thirty years ago, at Chile’s Las Campanas Observatory, Ian Shelton was engaged in an off-duty project. He tested a repaired telescope by photographing the Large Magellanic Cloud, a satellite galaxy to our own. After he developed the picture, he discovered a very bright star; walking outside, he sighted it visually. He had spotted the first naked-eye supernova since 1885. Word raced through the astronomy community. Every telescope in the southern hemisphere was turned to the “new star”.

Supernovae are common, but are usually located in dim, distant galaxies. This one was next door, in astronomical distances. It could be easily studied and its makeup determined. Supernovae are important. The violent explosion creates all elements heavier than helium. The atoms that make our bodies and everything in the Solar System were manufactured in the hellish temperatures and pressures of a supernova. As a result, we are all made of “star stuff.” While the remnant of this supernova is too far south for us to observe; the Crab Nebula, another supernova vestige in Taurus, is visible in amateur telescopes tonight.

Bookmark the permalink.