August Moon at Ascending Node – and Oh Yeah, A Total Solar Eclipse!

   Monday August 21st the new Moon will be crossing the plane of the ecliptic moving north relative to the ecliptic. This is known as the ascending node, one of two intersections the Moon’s orbital path has with the ecliptic. The ecliptic is actually the Earth’s orbit and the Moon’s orbit is inclined about 6o from the ecliptic. So there are two node intersections, the ascending and descending nodes.

   On August 21st the new Moon will be crossing the plane of the ecliptic at 10:34 UT (5:34 am CDT) within the constellation Leo the Lion. 8 hours later, at 18:30 UT (1:30 pm CDT), the Moon will reach new phase. This close timing between the new Moon phase and a node crossing means only one thing – eclipse!!

   My eclipse viewing area will be at an Elementary School in the North Kansas City School District. From that location totality will be approximately 80 seconds. This short video showing totality for 80 seconds, was clipped and edited from a video shot during the November 2012 total solar eclipse viewed from Australia.

   Read a bit more about this eclipse from a previous post.

      Does our Moon actually go around the Earth as many graphics show? 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 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.

Moon Passes Antares and Saturn

   Welcome to August!
   Over the next few days the Moon will wax from first quarter on Sunday July 30th into its waxing gibbous phases prior to reaching full Moon on August 7th. During this time, Tuesday August 1st to Thursday August 3rd, the Moon will first pass the reddish star Antares in Scorpius the Scorpion then the next day pass the outer planet Saturn on the 2nd. The following day has the Moon about mid-way across the Milky Way as the picture shows, however given the Moon’s bright reflected light it would be nearly impossible to see the Milky Way.
                           Click on a graphic below to see it larger               

   
   
   

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.

It’s The Final Countdown or Cassini Spacecraft’s Grand Finale

   Two months from this posting, September 15th, the Cassini spacecraft will end its mission at the planet Saturn by diving into the planet’s atmosphere and self destruction.
   This animated graphic shows the hourly position of the Cassini spacecraft as it makes a distant flyby of two of Saturn’s smaller moons, Atlas and Janus on July 19th. (the moons and spacecraft have been greatly enlarged to make them visible)
20 Years Ago
   On October 14, 1997, NASA launched Cassini, its largest interplanetary spacecraft, on a nearly seven-year voyage to Saturn. The voyage to Saturn was a two-part mission that included an orbiter and the Huygens probe. The Cassini orbiter was designed to explore Saturn’s system as it looped over, under, and around the planet’s many moons and rings. The Huygens probe was designed and planned for a study of the atmosphere and surface of Saturn’s largest moon, Titan, as well as a parachute-assisted soft landing on the surface. On September 15th the exploration phase of the Cassini mission will end as the spacecraft runs out of fuel and descends into Saturn’s atmosphere. As frictional forces tear the spacecraft apart, instruments on-board will send back data about the planet’s atmosphere.
35 Years Ago
   Typically, little is known about what happens after or before the active part of a mission. We know that the follow-up to a mission is the data analysis, which usually takes many years. What is generally not acknowledged is the lead-up to the official mission, which begins with the launch. The Cassini Mission was first proposed in 1982, 15 years before the actual launch. Several years of planning and coordination between NASA and the European Space Agency followed. By the end of the 1980’s, the mission had been approved and was finally launched in 1997. Thirty-five years will have passed since the inception of the Cassini mission and the demise of the spacecraft when it enters Saturn’s atmosphere.

    Where is Cassini Now?
    Cassini grand finale fact sheet
    Cassini mission
    Cassini mission timeline poster
    Four Days at Saturn video
    Grand finale

   
   
   

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.

Jupiter Has 2 More

   Outer planet Jupiter has probably more moons than have been counted so far. The greater majority of these satellites of Jupiter orbit in retrograde relative to the rotation direction of the planet. Satellites of any planet that orbit their ‘parent’ planet in retrograde are called irregular satellites to distinguish them from satellites that formed with the planet, and consequently would orbit in the same direction as the planet’s rotation.
   Two recently discovered satellites, bringing the known or at least suspected number to 69, are described via their respective URL with a very official looking but somewhat confusing at first glance bulletin. The links are to the MPEC (Minor Planet Electronic Circular) at the Minor Planet Center.
   Both of these satellites were discovered or co-discovered by Astronomers Scott Sheppard, David Tholen, and Chadwick Trujillo. Given the small size and challenges in imaging these satellites it is amazing that they were discovered. Read more about the discoveries at Sky & Telescope‘s web site.

    MPEC 2017-L47 : S/2017 J 1 click here
    MPEC 2017-L08 : S/2016 J 1 click here

       Take a tour around Jupiter and its many satellites. The sizes of the Galilean satellites, Io, Europa, Ganymede, and Callisto have been made larger than they would actually be given the size Jupiter used in the 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.

Don’t Panic, It’s Only A Towel!


   Thursday May 25th, or any day that is May 25th we celebrate, in our own way, (yes we do) the Book,
Hitchhiker’s Guide to the Galaxy
, by Douglas Adams. What is the significance of the towel? Click on the graphic to enlarge it to a readable size to find out.
   So be a hoopy frood and click on this link to visit the Towel Day web site.

   Overheard on Jeopardy: “42.”
And the answer is: “What is the meaning of life?”
   
   
   

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.

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.