Southern Colorado Skies / May 28 – June 3, 2017

Consider a planetarium program to help you plan your observations. There are many commercial products available; an excellent program (STELLARIUM) is available free at


Jupiter is well-placed during these late-spring evenings, and its cloud bands are visible in even a quality small telescope. See the photo below – the dark bands are called belts, whereas the light bands are called zones. The upper atmosphere of Jupiter is composed primarily of ammonia ice, ammonium hydrosulfide and water (see diagram), and is separated into distinct horizontal areas by a process similar to the formation of horizontal cells in the Earth’s atmosphere. Jupiter’s zones are relatively cold and allow the higher formation of ammonia ice, giving zones a lighter color; the warmer belts allow the darker clouds beneath the dissipated ammonia to become visible. Have a look!





















Wednesday (May 31)

Tonight the Moon will occult Rho Leonis, Magnitude 3.8. The closest times I could find were for Colorado Springs: Disappearance – 10 29 48 p.m.; Reappearance – 11 33 56 p.m.

Thursday (June 1)

First-quarter Moon at 6:42 a.m. MDT.

Saturday (June 3)

From 8:22 p.m. to 10:22 p.m. MDT, two moons of Jupiter (Io and Ganymede) will cast their shadows onto the visible surface of the gas giant.



Mercury (in Aries):

The bad news – Mercury is deep in the glare of the sunrise, and this is also the worst apparition of Mercury in 2017. The good news –┬áthe tiny planet┬ámay be visible about 25 degrees to the lower left of Venus (good luck!).





Venus (in Pisces):

Look for Venus low in the eastern horizon at dawn. This week Venus appears in its half-lit phase (called its ‘dichotomy’). Watch out for the Sun if you decide to view it with a telescope!

Mars (in Taurus):

Look for a faint orange “star” low on the northwestern horizon during late twilight. It’s about 22 degrees (see above graphic) to the lower left of dazzling Capella.

Jupiter (in Virgo):

Jupiter is high and bright in the south as night begins. That bright star to the lower left by about 11 degrees is Spica, the brightest star in the constellation Virgo. (See the short narrative, above, for more information about Jupiter.)






Saturn (in Sagittarius/Ophiuchus):

Saturn rises as night falls. but you can also spot it in the south during the early morning hours, to the upper right of the Sagittarius “teapot.” Reddish Antares is about 17 degrees (see above graphic) to Saturn’s right.

Uranus (in Pisces):

Lost in the glare of the sunrise.

Neptune (in Aquarius):

Low in the east-southeast before dawn – see last week’s graphic. (Watch out for the Sun while viewing through your telescope!)


The following data are based on my location in Pueblo West, Colorado. If you live well outside this area, you should consider checking this information for your location in order to be assured of accurate times, elevations, etc. If you’re unfamiliar with Iridium flares, check out my article at:

Sunday (May 28) 09:50:48 p.m. / Magnitude -8.0 / ENE / Elevation 46 degrees

Tuesday (May 30) 03:32:49 a.m. / Magnitude -4.7 / ESE / Elevation 28 degrees

Tuesday (May 30) 09:42:43 p.m. / Magnitude -4.2 / ENE / Elevation 48 degrees

Thursday (June 1) 03:28:39 a.m. / Magnitude -1.7 / SE / Elevation 32 degrees

Thursday (June 1) 04:40:24 a.m. / Magnitude -5.2 / E / Elevation 11 degrees

Friday (June 2) 03:23:38 a.m. / Magnitude -4.6 / SE / Elevation 31 degrees

Friday (June 2) 04:43:17 a.m. / Magnitude -5.3 / E / Elevation 14 degrees

Friday (June 2) 09:29:36 p.m. / Magnitude -4.8 / ENE / Elevation 53 degrees

Saturday (June 3) 03:17:28 a.m. / Magnitude -4.1 / SE / Elevation 31 degrees


These are too numerous to list here! If you’re serious, load the ISS DETECTOR app on your smart phone or tablet.

Carpe noctem

Dave Furry

Pueblo West, Colorado

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