Sun Enters Libra

310ct-view-from-earth   Tuesday October 31st the Sun in its apparent eastward motion along the ecliptic, moves out of the constellation Virgo the Harvest Maiden and into the constellation of Libra the Scales. 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 return to bobs-spaces.

October Moon at Descending Node, Again


   Sunday October 29th the waxing 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 10-day old waxing gibbous Moon will be over the southern horizon an hour or so after sunset local time. The Moon will be about 10o from the outermost, and 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.

Jupiter at Solar Conjunction


Thursday October 26th the planet Jupiter reaches conjunction with the sun, in effect behind the sun as we view the two from Earth. Jupiter will reappear later next month in the morning skies rising before the Sun rises.


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.

October Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), on Wednesday October 25th. At that time the Moon will more or less be at a distance of 31.76 Earth diameters (404,154 km or 251,130 miles) from the Earth.

   Does our Moon actually go around the Earth as this 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*

   On the day of the apogee the 6-day old waxing crescent Moon will be over the southwestern horizon at sunset local time. Were it not so bright the glow of the Milky Way in the background might have been visible. Saturn is visible, but it is low above the horizon.

*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.

Mars and Neptune at Heliocentric Opposition

neptune-view

   Monday October 23rd two of the outer planets, Mars and Neptune, will be at heliocentric opposition, that is on opposite sides of the Sun. On that day the two planets will be separated by 180o. Mars will have a heliocentric longitude of 163o while Neptune will be at a heliocentric longitude of 343o. (343o – 163o = 180o)
   
   
   
   
Caution: Objects viewed with an optical aid are further than they appear.
Click here to go to the Qué tal in the Current Skies web site for more observing information for this month.

Moon – Saturn Conjunction


   Monday evening October 23rd the thin 4-day old waxing crescent Moon will be within about 5o from the ringed planet Saturn. Both will easily fit within the field of view of a 7×50 binoculars.

   
   
   

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 Not In Scorpius

  According to the pseudoscience of astrology the Sun enters the constellation of Scorpio the Scorpion on Monday October 23nd. When in fact the actual position of the Sun is still within the boundaries of the constellation of Virgo the Harvest Maiden.

   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 return to bobs-spaces.

Orinids Meteor Shower 2017

   The Orionid Meteor shower reaches its peak on the morning of Saturday October 21st. Best viewing is looking toward the east to south part of the sky after midnight and before sunrise. Look for the stars of Orion – most find Orion from the 3 bright stars forming his belt. Look to the left from the belt stars for the bright reddish-orange star Betelgeuse (often pronounced ‘beetle juice’) that represents Orion’s right shoulder. A little further to the left from Betelgeuse is the radiant, the area where the meteors or shooting stars will seem to be radiating outward from.
   All annular meteor showers, like Orionids, and the more well-known August Perseids, are named for the constellation the radiant is located within. Meteor showers are the result of several factors including the reaction between the comet’s dirty, icy surface with the Sun’s radiant energy and the orbital path the Earth and comets follow around the Sun. All comets leave behind clumps or clouds of comet debris, their surface material, as they come closer to the Sun’s heat energy. Some of this comet debris is left along the Earth’s orbital path such that the Earth regularly passes through these debris clouds. As the Earth passes through the debris the small bits of rock enter the Earth’s atmosphere and as they heat from friction and melt they glow briefly appearing as streaks of light. Some meteors leave a bright glowing trail, called a train, for a few moments. The Orionids average around 20 meteors per hour, however this year estimates are that that number may go up to as many as 60 per hour.
   How the number per hour can increase is based on the debris cloud and where the Earth passes through it. The debris is cloud-like in its shape and there are parts of the ‘cloud’ where the particles are more numerous – the thicker parts of the debris cloud. Meteor showers, like the Earth’s orbit are pretty well known so part of the equation for determining the number per hour is based on knowing what part of the debris cloud the Earth will pass through. This year we apparently pass through a thicker part of the debris cloud.
   Hang on to your hat!

   
   
   

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.

The Moon and Venus

   Yesterday morning and this morning offered me an opportunity for getting some pictures of the thin waning crescent Moon as it rose, more or less, over Highway 50. Given the amount of wasted illumination going skyward this is at best not a dark viewing site! However for bright objects rising in the east the bright lights of car dealerships, and oncoming car headlights provide for an interesting foreground. Yesterday there were low-lying clouds above the horizon making it a waiting game for when Venus and the Moon were visible. I won!
   This morning the skies were very clear and I was able to get a picture of the 28.25-day old waning crescent Moon. New Moon is tomorrow 20 October at 2:12 pm CDT.
   That ‘dash’ you might have noticed to the left from Venus in yesterday’s picture were the lights from an airplane. This picture like the one today were shot with a 2-second exposure time. So the dash represents how much the plane moved in 2 seconds. And if you look carefully at this morning’s picture you will see 3rd magnitude Zaniah near -3.93 magnitude Venus, and 3rd magnitude Porrima near the Moon.

   
   
   

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.

Uranus at Opposition

view-from-uranus
   Thursday October 19th the outer planet Uranus reaches a position in its orbit around the Sun when it is on the opposite side of the Earth from the Sun. This coincidentally is known as opposition, and it is an orbital position which only the planets further from the Sun than the Earth may reach.

   At opposition the outer planet rises and sets in a fashion similar to our Moon when it is at full phase, in that the outer planet at opposition rises at sunset and sets at sunrise.

   On Thursday the outer planet Uranus will be several degrees from an even more outer planet, Dwarf Planet Eris. Both rise during the evening hours and are over the southwestern horizon before sunrise.

   
   
   
   
   
   

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.