The Moon and Uranus – They Are Not the Same Thing!

   Ok, so how can you Moon Uranus? Yeah I know – a sad, and bad joke. Let’s put it behind us.
   Sunday morning, August 13th, the 21-day old waning gibbous Moon rises within a few degrees from the planet Uranus. Both are within the eastern fish of the constellation Pisces the Fishes. Uranus ‘shines’ at just under 6th magnitude so it is possible to see the 7th main planet from the Sun with binoculars. However the reflected light from the Moon will brighten the sky more than enough to drown out the dimmer light from Uranus and most other stars in the area making them not visible.
   Not that it will be visible but near the Moon on the opposite side from Uranus is one of the dwarf planets, Eris. However at nearly 19th magnitude and almost 95.729 AU, (8,898,566,474 miles ; 14,320,854,563 km) from the Earth it is all but impossible to see without some serious amateur equipment, at an observatory, or with the Hubble Telescope. Add approximately an additional 1 AU (93,000,000 miles; 1,496,68992,000 km) to get its distance from the Sun.
   What did I say about enough of the ‘bad jokes’? This cartoon reminded me of the statement, “Captain, We’re orbiting Uranus searching for Klingons.”

   
   
   
   
   
   Speaking of Uranus here is a portion of the Orbits performance video showing Uranus and some of its moons.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.

Sun Enters Leo

10aug-view_from-earth
   Thursday August 10th the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation Cancer the Crab and into the constellation of Leo the Lion. This is the true or actual position of the Sun as opposed to the pseudoscience of astrology which usually has the astrological Sun one constellation ahead or east from the Astronomical Sun’s position.

   Read a little more about how astrology has the Sun incorrectly placed in a previous blog, and in another blog discussing the effects of precession.
   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to go to bobs-spaces.

August Moon at Descending Node

   Tuesday August 8th the just past full Moon, a waning gibbous Moon, will be crossing the plane of the ecliptic moving south. This is known as the descending node, one of two intersections the Moon’s orbital path (dark green line) has with the ecliptic.
   

   On the day of the node crossing the 17-day old waning gibbous Moon will be over the east-southeast horizon an hour or so after sunset local time. The Moon will be about 10o from the outermost, (8th), planet Neptune.
   
   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to go to bobs-spaces.

Full Moon – Partial Lunar Eclipse


   Monday August 7th the full Moon, just one day before it will be at descending node, passes through the Earth’s outer shadow and briefly crosses through part of the darker inner shadow, the umbra. This sets up a partial lunar eclipse.
   The Earth has two distinct shadows, an inner and much darker umbra, and the outer and fainter penumbra as this NASA graphic shows.
   This eclipse will not be visible across the continental United States.

    For additional information about this or other eclipses go to the Hermit Eclipse web site.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to go to bobs-spaces.

2017 Perseid Meteor Shower – Not A Good Year

   In reality this year’s annual Perseid Meteor shower will be affected by the Moon. The waning gibbous Moon will rise at about the same time as the constellation Perseus – the location for the meteors. With the bright reflected light from the Moon it will be nearly impossible to see any meteors.
   Also keep in mind that the numbers quoted for meteors per hour, the ‘ZHR’ or Zenith Hourly Rate, is an average not a guarantee that you will see that many. On a good peak night in some years I have seen 30 or 40 bright meteors per hour from dark skies. The best time is the few hours before sunrise as the Earth rotates your location into the direction the Earth is moving and sort of puts you face-on into the meteors.
(graphic source from Facebook with this URL: http://sci-techuniverse.com/) — link takes you to a non-existent web site, or to a Go-Daddy advertisement
Update: I did a search for the web site and found that the correct address is http://www.sci-techuniverse.com/, and after searching the web site I could not find this graphic. There is, however a write-up from last year about the Perseids.

   The peak time for the Perseids is August 12th and 13th but more specifically during the predawn hours of the 13th as the constellation Perseus is rising.
   
   
   
   
   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.

Juno at Jupiter-Update

   The Juno Spacecraft is now fully engaged in making its planned orbits around the outer planet Jupiter. Since arriving and orbital insertion the spacecraft has made 6 orbits around Jupiter sending back amazing images and advancing our knowledge of the planet and its role in the solar system.
   Showing my age but I can remember how excited I was during the Voyager 1 and 2 flybys of the outer planets Jupiter, Saturn, Uranus, and Neptune during the 1980s. It was 40 years ago, Voyager 1 September 5th1977 – Voyager 2 August 20th 1977, when the spacecraft were launched. While both were targeted for a Jupiter and Saturn flyby Voyager 2 eventually had its mission rearranged so that it would fly past all four of the outer giant planets in a mission called the ‘Grand Slam’ or ‘Grand Tour’. The images from those flybys were just as exciting as the images we see from the current Juno mission albeit improved after 40 years of imaging technology advances.
   So Where are the two Voyagers now? Click here to find out.
   Click here to go to the NASA Video web site to see a short video (15 minutes) about the Voyager mission to the outer planets. This is part of a video series I often used in my Planetarium and classroom during the 1990s – so please realize that the graphics and animations, as well as some descriptions and some explanations are not necessarily as ‘advanced’ as things are now. However two of my heroes, Dr. Edward Stone, and Dr. Andrew Ingersoll, are featured making comments about some of the Science and discoveries.
   Below is a well done video compilation of images taken by the Juno Spacecraft. Click here to go to the Vimeo web site for the original video.

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to return to bobs-spaces.

August Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), on Wednesday August 2nd. At that time the Moon will more or less be at a distance of 31.75 Earth diameters (405,934 km or 252,857 miles) from the Earth.
   On the day of the apogee Moon the 11-day old waxing gibbous phase, rises mid-afternoon and is about 3o from Saturn and around 14-15o degrees from the reddish star Antares in Scorpius the Scorpion. The Moon and Saturn will fit easily within the field of view binoculars.
   Does our Moon actually go around the Earth as the above graphic shows? From our perspective on the Earth the Moon appears to circle around the Earth. However, in reality, the Moon orbits the Sun together with the Earth*

*Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit”. (PDF)

Read this very informative article about the Earth-Moon system and their orbital motions, written by Joe Hanson. “Do We Orbit the Moon?”

   
   
   

Click here to go to the Qué tal in the Current Skies web site for monthly observing information, or here to go to bobs-spaces.