Jupiter - How Many Moons Does Jupiter Have?
Written by Tammy Plotner
When it comes to the mighty Jupiter - and seeing Jupiter's moons through a small telescope or binoculars - timing is everything. Jupiter's satellites are constantly on the move, and almost any time you observe you'll see at least one. The four largest of Jupiter's moons are known as the Galileans, and go by the names of Europa, Callisto, Ganymede and Io. But which one is which and how do you know what you're looking at?
Thanks to some very cool tools like Sky & Telescope's Jupiter's Moon you can tell exactly what time a Jovian event is about to happen and observe it yourself. For example:
Saturday, May 17, 2008
17:36 UT, Io's shadow begins to cross Jupiter.
18:42 UT, Io begins transit of Jupiter.
19:54 UT, Io's shadow leaves Jupiter's disk.
21:00 UT, Io ends transit of Jupiter.
What transpires will look very much like this awesome photo done by Paul Haese. Jupiter Transit events are easy to observe even with a small telescope, but it does require some techniques. First of all, you cannot simply glance in the eyepiece and see it happening with ease. It does require higher magnification and patience! The trick is to get comfortable and just watch… During your extended observing session, moments of stability will come and go and it won't take long before you notice a phenomena that recurs. The body of Jupiter's moons are a little more difficult to spot, but the shadow becomes very easy when you take your time and really look!
So what happens if your equipment or skies aren't up to the task? Never fear… You're not left out of the game. Timing is everything. Begin by observing Jupiter well in advance of the event and take note of the Galilean moon's position. By checking every few minutes or so, you will notice when one is about to go into transit because you'll see it near Jupiter's limb. Keep watching… Because it will simply disappear! (This is also a great clue for larger telescopes to understand where to look and where the shadow will appear.)
While viewing through the average telescope isn't going to be as good as what can be seen photographically, just timing and participating in an event is a wonderful opportunity to expand your astronomy knowledge and experience. Watching a Galilean moon transit Jupiter, or Jupiter's Red Spot is something which can be done from light polluted skies and doesn't require a lot of technical skills - just patience. Mark your calendars for 3:50 Universal Time on May 22nd when Jupiter will appear to have no moons at all! Try following the event in advance of the predicted time and report what happens. So how many moons does Jupiter have? The real answer is 63. But the question should be…
How many can you see?
This incredible image of an Io transit was done by Paul Haese, a member of MRO, using a Peltier cooled C14 and Skynyx 2-0 monochrome camera with RGB Astronomik filters. Paul's planetary imaging skills are legendary. The UK has Damien Peach, the US has Don Parker and AU has Paul Haese! Thank you so much for sharing…
Filed under: Astronomy, Astronomy For Kids, Jupiter
May 17th, 2008 at 2:53 pm
Cuando llega el momento del poderoso Júpiter —y observar sus lunas por telescopio o prismáticos— la sincronización lo es todo. Los satélites de Júpiter están moviéndose constantemente y casi siempre podrá verse al menos uno. Las cuatro lunas más grandes de Júpiter, conocidas como los satélites galileanos, son: Ío, Europa, Ganímedes y Calisto. ¿Pero cuál es cuál y cómo sabemos qué luna estamos viendo? [...] Fuente: Tammy Plotner para Universe Today.
May 18th, 2008 at 8:06 am
The real answer is that we have no idea how many moons Jupiter has. We have found 63 so far.
May 18th, 2008 at 7:16 pm
I ought to know… it's crazy out there.
May 18th, 2008 at 10:03 pm
We can see only light and lighted objects. We can see nothing in the darkness. A thing may how much bigger if it goes away to away from our eye views, the thing appears us smaller to smaller and at last it will disappear from our eye views. The sun is the only object who gives light the entire solar system. In size it is 3 lakhs time bigger than earth but we look it like a football size. From calculation we know that sun is about150 millions Kilometer away from the earth. So we can find earthlike object at same distance must be disappeared. Since we are created from earth, the eyes power of us has merged with the earth. Since the earthlike object disappears at distance of 150 million Kilometer, the eye powers see anything ahead of it, is zero.
So we are capable to see original objects within the area of 150 million kilometer of solar system only. Next we are covered by two mirrors. One is on point of sun another is on the point of earth’ shadow. Each mirror reflects reversely about 75 million kilometer meets another mirror as result unlimited reflection occurred in both side and we find very deep space on the side of darken earth and find sun spots on sun.
Visit: - http://www.spacemirrormystery.com and know about the real Jupiter.
June 4th, 2008 at 3:53 am
Pradipta,
Just seen the space mirror site.
Sorry, it doesn't seem to make any sense whatsoever.
if it's a spiritual-type thing fair enough,that's what you're into (live n let live & all that), but the site doesn't offer up any actual evidence
June 29th, 2008 at 2:04 am
After reading the above comment about our Sun lighting all,— Just a curiosity question- how many light years away is Orion's nebula, & is it considered to be part of our galaxy to be illumined by our Sun. Please correct me if I am wrong,but I have been lead to believe that there are many,many stars visible,of much greater brilliance & power & size than our Sun, that could devour our Sun in an instant, and so Mr Pradipta, I feel your comments are as space dust- a hindrance!