ISS This Morning

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   This morning I braved the chilly temperature and caught the International Space Station as it orbited a little to the north over my space on the surface.

         A great way to start the end of the year!

   This graphic is a screenshot from my cellphone showing the display from ISS Detector, an extremely useful APP for Android and IOS and tablets like my Kindle Fire.
   
   
   

   The track across the sky lasted about 7 minutes. It started in the west and then followed a path between the two ‘Dippers’ passing the Pointer Stars in the Big Dipper on the way toward Polaris, the North Star.

   
   
   Camera Settings: 18 mm; 3.5 sec. F5.6; ISO 1600

   
   
   

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.

Moon Near Venus


   Sunday evening January 1st the 4-day old thin waxing crescent Moon will be within 5o to the west (right) from the inner planet Venus.

   Below is a picture of the Moon and Venus through the clouds this evening.
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   

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.

Mars Moves Into the New Year

   Over the next several days Mars will catch up with and then pass by Neptune coming within less than 0.5o on December 31st. Mars moves at a daily rate of about 0.5o while Neptune moves about 0.006o each day. If you were on Mars observing Neptune you would see Neptune begin its retrograde motion. Interestingly from here on Earth Neptune has just ended its retrograde motion. It’s all relative as somebody probably said.
   Both planets will be above the southwestern at sunset local time with only Mars being visible without the use of an optical aid.
   Comet 45P/Honda-Mrkos-Pajdušáková may be bright enough to be visible with binoculars and certainly with a telescope, and definitely should make for an interesting picture with the waxing crescent Moon nearby.
   
   
   
   

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.

Neptune Moves Forward and Sees Red

   Thursday December 29th the outermost of the 8 planets, Neptune, ends its westward retrograde motion around the Sun and will resume direct motion, moving eastward as we view Neptune from the Earth. In this graphic the location of Comet 45P/Honda-Mrkos-Pajdušáková is shown. Keep watching that space as on the 31st the thin waxing crescent Moon will be near the comet.
But wait…
still more cosmic thrills…

mars-neptune-tele   Currently located in the constellation Pisces the Fishes Neptune will be joined by the red planet Mars on New Year’s Eve when the two will be separated by less than 0.5o as seen in this simulated view through a 25mm eyepiece on an 8″ Reflector. Mars has an apparent magnitude of 0.88 compared with Neptune’s apparent magnitude of 7.8. And for a real comparison check out Venus shining at an apparent magnitude of -4.32.

   Retrograde motion is an apparent motion that the outer planets, relative to the Earth, have. It is an apparent motion that looks as if the outer planet stops it normal direct motion to the east and reverses direction to the west. After a period of time the apparent westward motion ends and the planet resumes its normal orbital path to the east. Retrograde motion happens as the faster moving Earth catches up with and then passes by the outer planet. It is during this time that the backward apparent motion happens.

   The two inner planets also have retrograde motion but it is a result of their orbit around the Sun and not the Earth passing them by. For approximately one-half of their orbit they move east, from western elongation through superior conjunction to eastern elongation. Then at eastern elongation the inner planet starts moving westward through inferior conjunction to western elongation.

   Read a little more about retrograde motion in my February 2012 Scope on the Skies column, drawkcab planets, in Science Scope Magazine.

   
   
   

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.

A Comet Comes This Way

   Comet 45P/Honda-Mrkos-Pajdušáková is a short period comet having an orbital path that takes it from beyond the orbit of Jupiter around the Sun approximately every 5.25 years. This current apparition has the comet starting to become brighter and more visible as it approaches its closest to the Earth on February 11th. On that date it will be visible in the morning skies before sunrise at a distance of 0.084 AU (7,808,288 miles; 12,566,221 km) from the Earth with an estimated apparent magnitude of 8.0.
   Click here to read more and see some viewing graphics.
   An important caveat about comet predictions:
“A comet is like a cat. Both have tails and both do what they want.”

   
   
   

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.

Mercury at Inferior Conjunction

orbital-positions   Wednesday December 28th the innermost planet Mercury reaches inferior conjunction. At inferior conjunction Mercury will move between the Earth and the Sun – much like the position of the Moon at new phase. The graphic to the right shows the planet positions relative to the Earth and Sun for both inner planets and outer planets.

mercury at inferior conjunction   While at this inferior conjunction Mercury will not be directly in line with the Earth and the Sun – on the ecliptic. Mercury has an orbital inclination of 7o with respect to the ecliptic. So like our Moon, Mercury during each complete orbit, will cross the plane of the ecliptic moving north (ascending node) and also moving south (descending node). In this situation Mercury is north of the ecliptic after its recent ascending node on December 20th.

   
   
   

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.

December Apogee Moon and A Special BirthDate

25dec-apogee_moonOur Moon reaches apogee, (greatest distance from Earth), on Sunday December 25th. At that time the Moon will more or less be at a distance of 31.80 Earth diameters (405,870 km or 252,196 miles) from the Earth.
   A Special Birth Date:
   Centuries ago on December 25th a birth occurred that would later lead to a knew understanding of the universe and our place within the universe. Were he alive today Isaac Newton would be 374 years old. Happy B-Day Isaac!
   But wait! Was Isaac Newton born on December 25th 1642, or January 4th 1643? At that time there were two calendars in use and the part of England where he was born had not yet switched to the new Gregorian Calendar which would have his birthdate in January rather than December as shown on the Julian Calendar. Here is an interesting explanation about this.

   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?”

   
   The nearly new Moon, a 26-day old thin waning crescent Moon, rises about 2 hours before the Sun.

   
   
   
   

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 Jupiter at Heliocentric Opposition

31oct-view-from-mars   Thursday December 22nd the planets Mars and Jupiter are aligned in an arrangement known as heliocentric opposition. The two planets are on opposite sides of the Sun and are approximately 180o apart in heliocentric longitude as measured around the celestial equator. Mars has a heliocentric longitude of approximately 10o, while Jupiter is at 190o. However the two planets are not necessarily at the same level (above or below) relative to the ecliptic. Both planets are south of the celestial equator with Mars at 12o South Declination in Aquarius the Water Bearer, and Jupiter, at 6o South Declination, is in the constellation of Virgo the Harvest Maiden.

   
   
   

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.

ISS, Mars, Venus, and Clouds

   It was the best of times, no actually it kind’ve sucked as the somewhat clear skies started to cloud over! I had plans for catching the ISS as its orbit over my part of the world took it between Venus and Mars as it traversed my skies from west to southeast this evening (20 December). With some image processing I was able to tweak out the ISS in most of the 26 images stacked to make one of pictures you see below. The other one…colorful.

   Camera settings were 18mm; ISO 800; F6.0; 3.2 sec. Pictures stacked using StarStaX. StarStaX is available as Freeware for Mac OS X, Windows and Linux.

   
   
   

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.

Moon Passes Gas


   Over the next couple of nights, December 21st to 22nd the last quarter Moon will pass by the gas planet Jupiter coming within about 2o at 18 UT (12 pm CST) on the 22nd. The Moon rises around 2-3 hours after midnight local time and is over the southeastern horizon in the hour or so 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.