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The following is a discussion of just a few of the many objects that may be seen up in the sky, this week Sunday June 15 to Saturday June 21, 2008.

International Space Station

No passes are visible from the Denver area this week.

Sun

As of the date of this report (Sunday) there are no regions currently visible on the solar disk. The summer solistice occurs at 5:59 pm MDT on Friday June 20th. This has not occurred on June 20th since 1896. Usually the solistice is on June 21st or 22nd. "Early" solistices will happen more frequently for the next two hundred years due to the leap year correction cycle of our Gregorian calendar. A "leap day" is periodcially inserted to the Gregorian calendar at the end of February to keep Easter Sunday within a couple weeks of the spring solistice. Sunday Jun 15 sunrise is at 5:33 am and sunset is 8:33 pm On Saturday Jun 21 sunrise is at 5:34 and sunset is at 8:34 pm MDT

Planets

The planet Mars is visible low in the west in the constellation Leo, and is about 23 degrees above the horizon around 9:30 pm. It is 191 million miles (2.05 au) away and magnitude +1.6 in brightness and the semi-diameter is 4.6 arc sec. Saturn is about 9 degrees above and to the left of Mars in the constellation Leo. It is magnitude +1.2 in brightness and the semi-diameter is 17 arc sec. Jupiter rises at 9:40 pm by the weeke3ndis visible -2.5 magnitude in brightness and the semidiameter is 47 arc sec. The great red spot crosses the center at the following times this week: Sun Jun 15 at 02:03 am Tue Jun 17 at 03:41 am Tu Jun 17 at 11:33 pm Thur Jun 19 at 05:19 am Fri Jun 20 at 01:10 am Sun Jun 22 at 02:48 am Sun Jun 22 at 10:40 pm

Dwarf Planets

The second largest dwarf planet, 134340 Pluto, is at opposition on June 20th at distance of 2.9 billion miles. It is in the constellation Sagittarius and is magnitude +13.9 in brightness. In dark skies it should be possible to see visually with a 10 inch or larger scope. A detailed star chart or very accurate 'goto' is needed to locate it. (Location on 2008-Jun-21 00:00 is RA 17 58 45 Decl -17 02 28). The largest dwarf planet, 136199 Eris is in constellation Cetus, It is magnitude +18.7 in brightness and much dimmer than the visual limit of any amateur telescope, It should be possible to image it with large scope and ccd camera however. The other dwarf planet, 1 Ceres, is in constellation Gemini. It is not visible at the present time as its currently obscurred by the bright sky at sunset.

Asteroids

3 Juno is in constellation Ophiuchus. and is magnitude 10.1 in brightness. (Location on 2008-Jun-21 00:00 is RA 17 22 12 Decl -04 29 54).

Moon

Sun. Jun 15 Lunation is 11: Lunar 1 targets are Vallis Schrooter, Aristarchus, Oceanus Procellarum, and crater Billy. Mon Jun 16 Lunation is 12: Lunar 1 targets are Sinus Roris, Reiner Gamma, and crater Schichard. Tue Jun 17 Wed Jun 18 Lunation is 14:Moon is full at 11:30 am MDT. Look for rays extending from prominent craters and bright albedo features such as Aristarchus.

Dark Sky

Not much this week!