May Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), for this orbit, on Monday 18th. At that time the 26.5-day old waning crescent Moon will be at a distance of 31.88 Earth diameters 252,028 miles (405,600 km) from the Earth.

   On the day of the apogee the thin waning crescent Moon rises about 1-2 hours before sunrise local time. Looking carefully with binoculars you may be able to see nearby 4th magnitude star 20 Ceti, one of the many stars that are part of the constellation Cetus the Whale.

   

   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*

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

   
   
   
   
   
   
   
   
   

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.


Also Follow me and other great resources at Feedspot.

Mars – Jupiter at Heliocentric Conjunction

   Saturday May 16th the outer planets Mars and Jupiter will reach a point in their respective orbit that has them at nearly the same heliocentric coordinates. This a system of tracking the planets as they make their 360o orbit around the Sun. Each Sun orbiting object’s orbital position is measured using degrees, minutes, and seconds of heliocentric longitude. Each object orbits the Sun at a daily rate determined by dividing 360o by the number of days an object takes to complete one orbit around the Sun.
   As the above graphic shows the two planets are arranged in a straight line out from the Sun. The Earth is not part of the line-up. This is a heliocentric view of their orbital positions with the Sun at the Center. A heliocntric longitude based view is not the same as a view from the surface of the Earth where there is a distinctly different view of the two planets.


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.


Also Follow me and other great resources at Feedspot.

Say it Ain’t So!


   According to the web site Physics-Astronomy on May 16th the crescent Moon will be in a conjunction with the inner planet Venus and an outer planet, Jupiter, in a formation looking like a smiley face.

   This type of conjunction has happened in the past including one in 2 B.C. that has been suggested to be the ‘Star of Bethlehem’. More recently this triple conjunction did happen in December 2008, according to the article.
   Click here to see a list of future planetary conjunctions.

   Looking down from above the solar system on May 16th showing the orbital positions of Venus, the Earth, and Jupiter. From this graphic it shows that from the Earth you would have to look toward different directions to see either planet.

   No this will not happen.
   Here are reasons why this article about the conjunction is “fake news”.

   Venus is visible in the evening skies at sunset over the western horizon and sets around 9-10 pm local time. (Rises: 7:23 am – Sets: 10:24 pm)
   Jupiter is visible in the morning skies over the southern horizon and sets during the afternoon local time. (Rises: 12:45 am – Sets: 10:47 am)
   The article does not indicate which crescent Moon. Is this a waxing crescent Moon in the evening or a waning crescent Moon in the morning?
   The Moon is in fact a 22.8-day old waning crescent Moon in the morning skies. However the Moon is closer to Neptune and Dwarf Planet Ceres than it is to either Venus or Jupiter.



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.


Also Follow me and other great resources at Feedspot.

Moon Mars Conjunction x2

   Thursday morning May 14th the last quarter Moon will be about 8-9o to the west from the ‘Red Planet’ Mars. The following morning, Friday May 15th the waning crescent Moon will be about 6-7o from Mars but this time on the east side.



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.


Also Follow me and other great resources at Feedspot.

Moon-Jupiter-Saturn Conjunction

   Tuesday morning May 12th, before sunrise, the 19-day old waning gibbous Moon will be within a few degrees from the outer planets Jupiter and Saturn. All three will fit within the field of view of 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.


Also Follow me and other great resources at Feedspot.

Saturn at Western Quadrature – 2020

saturn-west-quadrature   Tuesday April 21st, the position of the planet Saturn with respect to the Earth and the Sun places this ringed planet at what is called western quadrature. Saturn is at a 90 degree angle from us as this graphic shows. Think third quarter Moon as that is a fair comparison of the relative positions. At this position Saturn leads the Sun across the sky from east to west as the Earth is rotating, meaning that Saturn rises before the Sun and also sets before the Sun.

Saturn currently is within the constellation of Sagittarius the Archer as this graphic shows. From the northern hemisphere, looking toward the southern horizon, you can find Saturn over the southeastern horizon about midway between Mars to the east, left, and Jupiter to the west, right.

Learn a little (or a lot) about Saturn by visiting the Cassini at Saturn mission web site.
Click here to go to the Cassini Mission web site.

   This is a short 5 minute video I made as part of a live musical performance called “Orbit”. This is a piece from the much longer tour of the solar system performance and video and shows Saturn and some of its moons as viewed from the Cassini spacecraft that month.

   
   
   


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.

An ‘Old’ April Moon at Apogee

   Our Moon reaches apogee, (greatest distance from Earth), for this orbit, on Monday April 20th. At that time the new Moon will be at a distance of 31.86 Earth diameters 252,563 miles (406,641 km) from the Earth.

   On the day of the apogee Moon the 27.2-day old thin waning crescent Moon will be rising about 1 hour before the Sun rises and if spotted could become a personal record for seeing an ‘old’ Moon.

   While out looking for the Moon there are several planets arranged across the southern and southeastern horizon. They are arranged west to east (or east to west) along the ecliptic, the Earth’s orbital path around the Sun, as the two graphics below are showing.

   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*

   *Click here to read my 2006 Scope on the Sky column “The Real Shape of the Moon’s Orbit” in NSTA’s Science Scope Magazine.

   
   
   
   
   
   
   
   
   

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.


Also Follow me and other great resources at Feedspot.