Skylights featured on Astronomy Picture of the Day

Scout Report Selection Webivore Selection SpaceCareers Selection

Skylights featured nine times on Earth Science Picture of the Day: 1 2 3 4 5 6 7 8 9


Photo of the Week. Sirius and Canis Major. Shining through light clouds, Sirius is surrounded by a rare sight for a star, a diffraction corona of the kind normally seen around the vastly brighter Moon. See it at full resolution.

Astronomy news for the three-week period starting Friday, May 29, 2009.

The next Skylights will appear Friday, June 19. Thanks for your patience.

During our extended Skylights period, the Moon runs through a good fraction of its phases, beginning with first quarter the night of Saturday, May 30 (preceded by one night of a fat waxing crescent). After almost a week waxing in the gibbous phase, the Moon then passes through full during the day on Sunday, June 7 (thus appearing a bit after full by Moonrise that night). The waning gibbous is then followed by third quarter on Monday the 15th. We finally finish the interval with the Moon in the waning crescent as it heads toward new on Monday the 22nd. The Moon passes apogee, where it is farthest from Earth, on Wednesday the 10th.

As it makes its lunar rounds, the Moon puts on an especially nice display with stars and planets. It all starts with a bracketing of Saturn, wherein the night of Saturday, May 30, the Moon will be seen to the southwest of the planet and the following night to the southeast of it. In the "big event," the Moon will then not only pass the bright star Antares in Scorpius the night of Saturday, June 6, but actually occult it for much of North America, though the brightness of the near-full Moon and twilight will make it tough to see and it will really require binoculars or a telescope. The timing depends on location. For the eastern two-thirds or so of the US and southern Canada, the star disappears behind the Moon's leading edge roughly between 9 and 10 PM Daylight time. Reappearance, visible everywhere except the far northwestern corner of the US, takes place about an hour later.

The Moon then takes on the gang of planets that are now hugging the morning hours and dawn. As the Moon bracketed Saturn the beginning of our period, it then brackets Jupiter, but lying to the NORTHwest of the giant planet the morning of Saturday the 13th (the night of the 12th), then to the northeast the following morning/night. Our three-week journey continues the morning of Friday the 19th with the Moon making a fine appearance just above Venus and Mars, Mars up and to the left of its much more brilliant neighbor. More quietly, Neptune and Uranus get passed on the Saturday the 13th and Tuesday the 16th.

Then it's the planets themselves that are on display. The big event here is the fine conjunction between Venus and Mars that takes place the morning of Friday the 19th, Mars just two degrees to the north of Venus, the two rising together around 3 AM. Not to be entirely outdone, on Monday the 15th, giant Jupiter halts its eastern motion against the stars that lie along the border between northeastern Capricornus and southwestern Aquarius, and begins its retrograde trek to the west. As May ends, Jupiter also formally becomes an evening planet, rising at local midnight (1 AM daylight), then rising after midnight Daylight Time around Sunday the 14th.

On Friday, June 5, Venus passes its greatest elongation 46 degrees west of the Sun. Then it's Mercury's turn, the little planet going through its greatest western elongation on Saturday the 13th. Rising in mid-dawn shortly before sunrise, the view of Mercury, while never good, improves some as the month proceeds. Finally, it's back to the evening, when we see Saturn in the southwest as the sky darkens, the planet still in southeastern Leo to the east of Regulus. The ringed planet makes something of a transition when as of around Sunday the 14th, it begins to set after local midnight, about an hour after Jupiter rises.

In early evening, the Big Dipper of Ursa Major rides high, dominating the sky. It makes a fine transition to Bootes, the Herdsman, which lies to the southeast of it. Just follow the curve of the Dipper's handle to bright, orange-colored Arcturus, the northern hemisphere's brightest star. Then continue the curve down to blue-white Spica in Virgo. To the southwest of Spica you can admire the small box of stars that makes Corvus, the Crow, while to the southeast of Spica lies another distorted box that makes most of Libra, the Scales. Then, its off farther into the southeast to Antares of Scorpius, the star that will be occulted by the Moon the night of Saturday the 6th.
Valid HTML 4.0!