SCAS – Southern Colorado Skies, July 12-18, 2015

SCAS rework Logo 3 Color copySCAS – Southern Colorado Skies This Week

Consider a planetarium program to help you plan your observations. There are many commercial products available, and a very good program (Cartes du Ciel) is available free at http://www.ap-i.net/skychart/en/start.

All Week:

  • The Milky Way was thought to be a continuous band of light (the “via lacta” or “milky circle”) until Galileo pointed his telescope upward in 1610 and determined that it is composed primarily of individual stars. When you look at the Milky Way you are seeing our home spiral galaxy edge on, with the center located just to the right of the Sagittarius “teapot.” It’s diameter is estimated to be as large as 180,000 light-years and is estimated to contain as many as 400 billion stars! And there are literally billions of other known galaxies in the universe! Away from the city lights you can see the Milky Way in its glory all week, in particular from Cygnus (the swan) to Sagittarius (the archer) as you look almost straight up down to the south.
  • Can you find the Big Dipper? Then you can easily find two other popular stars: Polaris (the North Star), and Arcturus (in Bootes the herdsman). Follow the two end stars in the ‘bowl’ of the Big Dipper about 5 times their separation distance to the north (you are already facing pretty much north to even see the Big Dipper) and voila – there is the North Star. Now find the three-star “tail” of the Big Dipper and follow its curve away from the dipper and you will be rewarded by finding yellow-gold Arcturus. Remember the phrase: “Arc to Arcturus.”

 Tuesday (July 14):

  • Jupiter and Venus are still close together in the western sky as darkness falls. Look for bright Regulus (the “heart” of Leo the Lion) a couple degrees above Venus.
  • The spacecraft New Horizons will be whizzing past Pluto today. Pluto is to the upper left of Sagittarius in the southern sky, and in a good position for capturing in a camera but be warned it’s hard to find because it’s a magnitude 14 object. Also, the spacecraft Dawn is orbiting Ceres today (magnitude 7.7). Ceres is hanging out just below Capricornus (rising in the southeast about 11 p.m.).

 Wednesday (July 15):

  •  New Moon at 7:24 p.m. MDT.

Saturday (July 18):

  • The very thin crescent Moon (west at dusk) will be just to the left of Venus, with Jupiter further to the right and Regulus hovering over it all.

PLANETS:

Mercury (in Gemini):

Might be visible in the early sunrise (just north of east) and next to Mars early in the week. Have a look (binoculars will help) about 20 minutes before sunrise.

Venus (in Leo):

Still fairly close to Jupiter – look west at sunset.

Mars (in Gemini):

See Mercury, above.

Jupiter (in Leo):

Still close to Venus – look west at sunset.

Saturn (in Libra):

High in the south as darkness falls. Look for it just above the “head” of Scorpius.

Uranus (in Pisces):

Well up in the east-southeastern sky before dawn.

Neptune (in Aquarius):

Well up in the southern sky before dawn.

IRIDIUM FLARES and INTERNATIONAL SPACE STATION:

Sorry – these are too numerous to list here! If you’re serious, load the ISS DETECTOR app on your smart phone or tablet. Alternatively, refer to Chuck Percival’s column in the Sunday Pueblo Chieftain.

Have fun!

– Dave Furry, Southern Colorado Astronomical Society