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[Chicago Astronomer - Astro Joe]

Watch The Two Brightest Planets Kiss In Twilight

From Spacedaily.com:

Cambridge MA (SPX) Aug 22, 2005
Anyone who looks low in the west early on a clear evening for the next couple weeks will witness an unusual sight. Venus and Jupiter, the two brightest planets, will draw closer and closer together from day to day, will then have an eye-catching conjunction (close pairing) on the evenings of August 31 to September 2, 2005, and then will begin to move apart.

The direction to look is low in the west-southwest, and the best time is about 40 to 60 minutes after your local sunset. The brightest of the two "stars" shining there will be Venus. Jupiter closes in on it from the upper left during August and passes closest to it on September 1st, when the two will appear separated by hardly the width of your finger held at arm's length (about 1.2 degrees).

Also in the vicinity is the much dimmer star Spica. If Spica isn't bright enough to show through the twilight, binoculars should reveal it easily. In addition, the waxing crescent Moon joins the party on September 6th and 7th.

Accompanying this release is a series of daily sky scenes that illustrate what to look for in the fading twilight on any date from August 21st through September 7th. They can also be played in sequence as a QuickTime movie to show the dance of the planets, Spica, and the Moon throughout this period.

Although these objects appear the same distance away as you watch them in the deepening dusk, this is very much an illusion. Venus is roughly 106 million miles from Earth (its distance changes during the period illustrated), while Jupiter is 575 million miles away, more than five times farther. The Moon is about 220,000 miles distant; Spica lies 1.5 quadrillion miles in the background.

Such big distances are better expressed by how long it takes light to cross them. Venus is about 10 light-minutes from Earth. Jupiter is 52 light-minutes from us, the Moon is only 1.2 light-seconds away, and Spica is some 260 light-years away. The light reaching your eyes from these sights has been in flight for very different amounts of time - something to think about when gazing at this unearthly view.

[Centaur]

Joe, I assume you meant conjunction and not occultation. As viewed from the Adler Planetarium the closest approach between planetary centers will be 1.2° on 2005 SEP 01 at 16:37 CDT (daytime) with an elongation 39.1° east of the Sun. The Moon will not be in the vicinity. I was planning to give notice of this event after the occurrence of this month's juxtaposition between the Moon and Pleiades.

In 2000 the separation between the two planets was only 1 arcminute. In 2004 it was 33 arcminutes. On 2006 NOV 15 it will be 26 arcminutes.

In 1818 Venus totally transited Jupiter. In 2065 Venus will partially transit Jupiter.

In 1998 Jupiter and Venus were simultaneously occulted by the Moon for observers in certain regions.

[Chicago Astronomer - Astro Joe]

Curt,

Sigh...Yea, I meant to say conjunction...

But, that's why I enjoy your participation here at the Chicago Astronomer...no one gets away with anything!... ;D

Thanks for the additional info.

[Centaur]

On 2005 SEP 01 at 21:43 UT geocentrically Venus will pass 1.2° south of Jupiter. That's about 2.4 times the width of the Moon. The bright star Spica in Virgo will appear about 6° away from the pair. The planets will be elongated 39.1° east of the Sun. Venus and Jupiter are normally the two brightest objects in the sky other than the Sun and Moon.

From Chicago the closest approach between the planets will occur at 16:37 CDT during daytime at a separation of 1.2°. In the early evening Venus will be seen below and to the left of Jupiter, still by about 1.2°. Spica will be to their left.

I've created a graphic previewing the grouping as it will be seen from Chicago's Adler Planetarium 30 minutes after sunset on Thursday, although it should well serve most northern hemisphere observers. To see it, click: www.curtrenz.com/astronomical.html