April Moon at Perigee

   The Moon reaches perigee, (minimum distance from Earth), this month on Friday March 3rd. At that time the Moon will more or less be at a distance of 28.17 Earth diameters (359,327 km or 223,275 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 perigee Moon the 1.5-day young thin waxing crescent Moon is above the western horizon at sunset local time and is near Dwarf Planet Ceres and the Pleiades open star cluster.

   *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.

Congress Downsizes the Solar System

   The US Congress today, in an effort to rectify the current sequestration budget cuts has made a dramatic announcement. In an effort to reduce the NASA budget, a resolution was passed today to downsize the solar system. According to an unnamed congressional staffer, House Republicans felt there has been “too much redundancy in the solar system” and that streamlining the 4.5 billion year old planetary system is long overdue. Such action would give NASA fewer places to go and this would allow the agency to carry out its space exploration goals within the funding profile that the House proposed earlier this summer.

   “Look, we have four terrestrial planets” said Congressman Rip U. Apart (R, OK), “and only one of them really works! So why not get rid of at least two of the others and clean up the neighborhood?” Most subcommittee members felt that while downsizing was definitely in the cards, eliminating both Mercury and Venus, or even Mars, was going too far. “We have too many international commitments to Mars.” said another politician. “So I think we should keep Mars and dump Venus and Mercury. It’s too hot to live on Venus, and liberal Democrats keep using it as an example of what climate change can do. So from a political and practical point of view, Venus has got to go.”

   Definitely at risk is the planet Mercury which lacks support because of its small size and poor visibility from Earth. “Who needs it?” asked Congressman Newt Onian (R, N.C.). “Have you ever seen it? I haven’t. So what good is it? We just don’t need useless planets. And speaking of useless planets, what about the asteroids? If you’ve seen one, you’ve seen them all. So I say we ought to get rid of the little boogers once and for all.”

   However, the downsizing recommendations do not stop with the terrestrial planets. The resolution also calls for a reduction in the number of gas giants which contain most of the planetary mass in the solar system. Most subcommittee members favor retaining Jupiter and Saturn, and eliminating Uranus and Neptune. “Jupiter employs the most molecules, and Saturn has those pretty little rings everyone likes.” said Rep. Con Mann (R, Fla.). “On the other hand, Uranus is a bore and its rings are dirty. And Neptune, for God’s sake, is just too far away.”

   The subcommittee was unanimous in its views towards Pluto which they deemed a moral misfit. “Now here’s a planet we can definitely do without.” continued Fornow. “Several years ago it was farthest from the sun (1979-1999), and now it’s not. It’s just too confusing. And now they tell me it’s really a Dwarf Planet. What the heck is going on here?”

   The resolution must now be presented to the entire House, where it is expected to pass easily since only a minority of Representatives have constituents on the affected planets. NASA Administrators have vowed to resist any further reductions to the solar system, saying that “NASA has expended considerable effort to make solar system exploration cheaper, faster, and better. Much of this work would be wasted if the solar system were downsized.”

   Critics say, however, that reducing the number of planets will not produce the expected savings to taxpayers. Textbooks, they note, would have to be revised to reflect the new arrangement, and facilities would need to be constructed to remove the planets themselves.

   April Fools!!

   
   
   

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 Cruises Past Planets and Stars

feb5-bino
   Over the next several evenings the Moon, as it orbits toward the east and waxes from crescent to first quarter phase will pass by several planets, dwarf planets, and star clusters. On the evening of February 5th the Moon will be close to the reddish star Aldebaran, the ‘eye’ in the face of the angry bull, Taurus. This should make for a nice view with binoculars or low power eyepiece when the Moon will sort of overlay the stars of the open star cluster the Hyades.

   These two animated graphics show the sky as viewed from Quito Ecuador at 0o latitude, and my home latitude of approximately 40o North. They show the sky at one day intervals starting with February 1st and ending with February 5th.


   
   
   

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 Near Pluto

(posting this ahead of time – on the road back to Quito and no Internet for a couple of days)

   Sunday morning January 29th the innermost planet Mercury will be about 1o from the the former outermost planet and now a Dwarf Planet, Pluto. Mercury with an apparent magnitude of -0.18 far outshines the 14.19 apparent magnitude of Pluto.
These two graphics show the sky as viewed from Quito Ecuador at 0o latitude, and my home latitude of approximately 40o North.

   
   
   

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.

Pluto Ducks Behind the Sun

7jan
   Saturday January 7th the Dwarf Planet Pluto reaches a point in its orbit where it is on the opposite side of the Sun as viewed from Earth. This is known as solar conjunction.

   
   
   

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 and Neptune Conjunction, inlcuding the Moon and Venus


   A previous post described the daily motion of Mars as it moves toward the planet Neptune. Well Monday evening January 2nd the planets Mars and Neptune, and our Moon (a 5-day old waxing crescent Moon) will all fit within the field of view of binoculars with Mars and Neptune separated by about 1.5o.

   In that post I had also mentioned that were Neptune observed from the surface of Mars then Neptune would be starting its retrograde motion. Actually I was not entirely correct as I was basing this on how the two planets looked from Earth rather than Neptune as seen from Mars. Compare the distance between the Earth and Mars and the difference between the orbital speed of the two planets. Then consider Mars and Neptune where there is a greater difference between the orbital speeds of Mars and Neptune as well as the distance between the Mars and Neptune then there is between the Earth and Mars.

   What this means is that Neptune, as viewed from Mars, will not actually begin to retrograde until around the middle of June.

   
   
   

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 Planet Buffet

   Friday night December 9th offers up a planet buffet featuring eight planets above the horizon and one under your feet. As this graphic shows one of the outermost of the 8 planets, Uranus, is above the eastern horizon as are two Dwarf Planets, Ceres and Eris, and the waxing gibbous Moon. Further west over the southern horizon is the outermost of the 8 planets, Neptune, and over the southwest horizon are Mars, Venus, Pluto, and Mercury. And under your feet? Look down to see the Earth – can’t miss it!
   Ceres is the closest Dwarf Planet to us as it is within the main asteroid belt between Jupiter and Mars. The other Dwarf Planet is Eris which at 96 AU is located much further than Ceres (2.2 AU) and Uranus (19.4 AU) and Neptune (30 AU).

   
   
   

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.