Moon, Venus, Jupiter – so what?!

Joe Carvalho captured the event nicely from his home in Fall River, MA. Venus is the brighter “star,” Jupiter the other one.

I urged folks to take a look at the unusual alignment of Venus, Jupiter and the Moon Monday night and I know several did and were suitably impressed – but I suspect a lot more reacted the same way as a good friend did – though they didn’t tell me 😉

He wrote:

I had a clear view of the event last night…. and my reaction was, “That’s interesting.” Yawn.

Essentially, he said “so what?!” OK, fair question. My immediate answer is to fall back on EInstein’s words:

“The most beautiful thing we can experience is the mysterious. It is the source of all art and science. He to whom this emotion is a stranger, who can no longer pause to wonder and stand rapt in awe, is as good as dead; his eyes are closed.”

So what? From my perspective the answer is if you ask this question your eyes are closed, you’re “as good as dead.” Ouch. That seems a bit harsh. Afterall, even if you are aware of thee science involved – and this individual certainly was – it’s next to impossible to be intuitive about it. Nothing in the science fits our down-to-Earth experiences. It’s all bigger than life – much bigger. So why should looking at this alignment of lights in the sky evoke an “experience of the mysterious” and thus leave us “rapt in awe?”

And for me the first answer is because it is mysterious. Science gives us great and useful answers about what we were seeing, but there is still much to know. Essentially we are seeing clear evidence of huge masses of matter being manipulated precisely by the most fundamental, pervasive – and weakest – force in the universe, gravity. And we don’t know what the heck gravity is – we know a lot about what it does, but what it is, well, that’s another question.

And think of what we consider big – an elephant? It’s a mere flea. OK, a mountain. We like to talk about the force to move mountains as if that were impossible. Well, the smallest thing we were seeing the other night was the Moon and it is loaded with mountains. A small telescope reveals them as tiny bumps on the surface. From our vantage point on Gooseberry we were noticing that one particular bump was mostly in the dark, but it’s peak was catching the first rays of the Sun. That meant that whole mountain was a tiny, pinprick of light along the dark portion of the dividing line between light and dark on the moon. That tiny speck was a mountain. The moon is so much larger than a mountain, it’s difficult to contemplate. That’s why I fear that the “facts” tend to run off our minds like so much water off the proverbial duck’s back. They don’t penetrate. But still – they can be helpful if you try to let them sink in – especially if you do this while experiencing an event such as viewing the Moon, Jupiter, and Venus all bunched up. So let’s go down that path a little.

The moon is relatively small in comparison to Venus. Get a 2-inch ball and put it next to a basketball and you have an idea. It’s diameter is roughly one fourth that of Venus, but the volume of Venus is far, far greater, And Jupiter? Well, it’s about 10 times the diameter of Venus (or the Earth) and that means roughly 1400 times the volume! Moving mountains is child’s play compared to moving these objects and constantly changing their direction as gravity does.

And speaking of moving, as we watch these three objects slowly set, we are spinning at an incredible 800 miles an hour – here in Westport, MA – faster if you’re closer to the equator, slower if you’re nearer to one of the poles. As folks looked at the Moon or one of the planets Monday night through one of my telescopes they would invariably say, sometimes with a little shock, “it moved out.” Nope – we moved. But we’re not used to seeing the impact of our motion – or we don’t think about it much. But do think about it. You are standing on what feels like solid ground and while there may be a little wind where you are, there’s nothing like the 800 miled per hour wind you have every right to expect from being on this extremely fast merry-go-round. So that’s a tad mysterious and awesome in itself, though easily explained by science. Hey, we’re not on the Earth, we’re init! We’re in a spaceship with a wonderful shield of atmosphere around us protecting us from all sorts of harmful stuff. That’s awesome and pausing to looka t a clestial displays uch as this, bring these things to mind.

But if you watched carefully for an hour or so you would have seen that the planets were setting – as I say, it’s really us spinning – faster than the Moon. What gives? Simple. The moon is whipping around the Earth at about 2,300 miles an hour and it’s going counter-clockwise. So while our spinning motion tends to make it appear to set – it’s in effect running against the motion – sort of 10 steps backward, one forward – so it doesn’t set as quickly as the planets and stars.

Again, speaking of motion, consider that all of this scene is in motion – we’re on a rotating platform that’s also moving at about 65,000 miles an hour around the Sun and because of this our view of Venus and Jupiter changes constantly – though slowly. Then we have the motion of Venus around the Sun at roughly 75,000 miles an hour and Jupiter at a much more stately speed of about 28,000 miles an hour.

Why is Jupiter slower? More distance between it and the Sun – the center of gravity – that all-pervasive force that is the weakest of the four forces – yet strong enough to keep us all in motion as if we were rocks on a cord of unlimited strength and being whirled about a giant’s head. What if someone cut the cord/ What if someone through the gravity switch to “off?” Would we know it instantly? It take slight form the sun a full 8 minute sto reach us – but gravity seems to cover the same 93 million miles – and much greater distances – in no time. Awesome.

But I call gravity a “force.” Einstein explained it as a geometry. What is it?

How about a mystery? And when I see an unusual alignment of three of the four brightest bodies in our sky – see these three brought so close together – from our perspective here on our merry-go-round – then I am reminded of all these things and more and I am, indeed, rapt in awe.

But what if you knew nothing of this? What if you had no scientific knowledge of what you were seeing? What if you were an illiterate pagan of today or some other time? Would you feel anything? I am sure several of the people observing with me the other night did not know these things – did not need to know them to be rapt in awe.

Why? I call on Wordsworth to help me out here – to give a far simpler and more direct answer to the question “so what?” – an answer that was as true two centuries ago as it is today.

The World Is Too Much With Us; Late and Soon
by William Wordsworth

The world is too much with us; late and soon,
Getting and spending, we lay waste our powers;
Little we see in Nature that is ours;
We have given our hearts away, a sordid boon!
This Sea that bares her bosom to the moon,
The winds that will be howling at all hours,
And are up-gathered now like sleeping flowers,
For this, for everything, we are out of tune;
It moves us not. -Great God! I’d rather be
A Pagan suckled in a creed outworn;
So might I, standing on this pleasant lea,
Have glimpses that would make me less forlorn;
Have sight of Proteus rising from the sea;
Or hear old Triton blow his wreathed horn.


Venus, Jupiter and Moon – why so different from Australia?


It was a stunning event and fortunately the clouds held off until we were done observing. Unfortunately, my camera battery died – I had forgotten to check – and I didn’t have a spare with me. So I only got a few shots of the early stages. Later it was a brilliant, awesome display and hopefully others in our small group had better luck with their photos. Stay tuned. I hope to update this post. These are the three brightest objects in our sky after the Sun!

Ahhh! David Cole of Westport got a much better shot that evening – here it is. (Posted 12.11.08)


And don’t forget to look tonight! No, the moon won’t be so close, but the planets still put on a great show and will for the next couple of weeks as they change position from night to night. Good way to get an intuitive understanding of why the ancients called these “planets” – a name which means “wanderers.” They’re also bright enough to see from even light-polluted suburban – and some city – skies.

Meanwhile, there are lots of good shots from Australia online here and this one was taken there by Guy Tunbridge. It’s interesting because the Australian alignment was much different than ours. Do you know why? Answer to come later, but feel free to add your explanation to the comments on this post. Note that not only is the moon oriented differently, but Venus and Jupiter have switched places.


Update 1: Does seeing them together help?


Ideally, your explanation will account for three changes:

  1. The side of the moon that is lit appears to change – or at leasr the orientation of it.
  2. In the US Jupiter is higher than Venus. In Australia this relationship is reversed.
  3. If you drew a line between Jupiter and Venus the orientation of the line would change.

If you stand on your head does it make any difference? (I no longer can do that so it’s a little hard for me to gather experimental evidence 😉

Life on a ball – so different, so good – take a look tonight!

Well, wherever you are on this wonderful ball, if you have clear skies when the sun drops below the western horizon, you’ll get a great show tonight! Actually, even if your skies aren’t clear tonight, take a look any time this week and you’ll get a good show. I plan to be out tonight with camera, binoculars, a small modern telescope, and a 200-year-old spyglass, just to see what I can see. But no optical aid is needed – this show’s for everyone and free!

This is the view from Downunder as depicted in the Sydney paper - it will look different here.

This is the view from Downunder as depicted in the Sydney paper - it will look different here.

I’m talking about the arrangement of the crescent moon and the planets Venus and Jupiter. You don’t need any optical aid for this show, but you do need a clear horizon and exactly what you see and when you see it depends on where you stand on this ball we call the Earth. Dom, my friend in Sydney, Australia, will see an astronomical smiley face, as his local newspaper told him. For us here in Westport, MA. the emoticon will be grimmer, but the show will still be spectacular! My comments from this point on all relate to what we see from Westport, MA, but will apply generally for most of the US. But again, exact times and view will differ – both because the sky is dynamic and because we live on the surface of – well, just inside the surface of, but that’s another story – a ball. I’ll explain in a moment.

Dark blue is good and the Clear Sky Clock prediction for Westport tonight looks like we'll get a cloud-free window. I'm keeping my fingers crossed!

Dark blue is good and the Clear Sky Clock prediction for Westport tonight looks like we'll get a cloud-free window. I'm keeping my fingers crossed!

The point is, start looking for this show near your western horizon about 20 minutes after local sunset. The darker it gets, the brighter things get – but the actors also move lower in the sky – by a couple hours after sunset it will be pretty much over. The most dramatic views are at dusk and that’s the best time to take pictures. (If you get any and want to share, please email them to me – I’d love to use them here.

All three charts that follow are made from Starry Nights software screen shots.

Here’s what can be seen from various locations.mvj_12108_westport

The view from Westport is to the southwest – azimuth 208° – and at 4:45 pm the grouping will be about 18 degree’s above the horizon – roughly two fists held at arm’s length. In Sydney, Australia – see below – the show will be higher and thus last longer. It will also be closer to due west – 261° and about 33 degrees above the horizon. Which means it will be in darker skies.

The moon, a bit more than three days old, will be the brightest, shining at about magnitude -10.6. Brilliant Venus, in a gibbous phase, will be shining at -4.1, and much more distant – but far larger – Jupiter will be shining at -2. For comparison, the brightest star in that general region of the sky will be Vega, at magnitude 0. (Vega will be a bit north of west (281°) and about 54 degrees above the horizon – quite high. It will probably “come out” a bit after Jupiter.

If you use binoculars, try to find a way to hold them really steady. The old spyglass I plan to use is about the same power as binoculars and I’ll try to steady it against a telephone pole or tree. My target will be be Jupiter and it’s four Galilean Moons – the ones Galileo spotted 398 years ago. These are a challenge for binocular users. They will look like faint stars on either side of the planet and very close. My guess is with luck you’ll see three of the four – and they should be easier to see before it gets totally dark. Under a real dark sky the glare of the planet may make them more difficult to see.

Here’s how they would look in a small telescope – this image is right side up, however, and most astronomical telescopes will reverse the view. I post it here in this way because it shows the order of the moons as they would be seen in binoculars at this time. Also note how they are in a straight line pretty much in line with the planet’s equator. Do keep in mind that in binoculars the planet’s disc will barely be detectable and the moon will be dim and close. Also remember that these moons change position hour-by-hour, so this view is for 4:45 pm EST.


What if it’s cloudy? What will you see on other nights this week? Don’t despair – this is a great show for a couple of weeks and very instructive to watch the changing relationships. By tomorrow night the moon will have gotten brighter and much higher and each night it will get brighter and higher. But that’s the usual moon routine. More fun will be to watch the dance of Venus and Jupiter. Each night Venus will get higher, Jupiter lower. So a week from now Venus will have climbed a couple of degrees higher, while Jupiter will drop lower each night. So on December 8, 2008, the view from Westport at 4:45 pm will be this:


What a dance! This is a great exercise for adults and children – observing and drawing – or photographing – the changing relationships. (Hope some teachers make this an assignmennt!)

Among other things it’s a great reminder that we’re all in motion. The Earth is spinning at about 800 miles an hour (Westport) and so each night, minute by minute, the planets get closer to our horizon. We’re also traveling at about 66,000 miles an hour in our orbit around our star and that changes our relationship to the two planets. But at the same time the planets are eaCH moving – Venus in a smaller orbit, Jupiter in a much larger one. They move at different speeds. So all the relationships are changing – and, of course, the moon is moving around the Earth.

You can check out these changing relationships by looking at the wonderful online Orrery here. Taking this view of things you will see how the reality of these motions around the Sun relate to the reality of what we see in our sky. (For pictures and more discussion on this aspect, see my earlier post here.) Then if you really want to put your brain in gear, try to figure out why the moon and planets appear so different from Australia!

Wow! Isn’t it a ball living on this ball?

(Well, in this ball. I really think we should dump that idea about living “on” the Earth. The Earth, quite thankfully, includes a thin, but protective shield called the atmosphere. It’s that atmosphere that we live in – we are like crabs crawling along the surface beneath a sea of gas. But without that atmosphere we wouldn’t be here – and if it weren’t so transparent – generally – we wouldn’t see any of this great show. So we’re really on a spaceship with a great life-support system and viewing port! )

Circle December 1- nice sky show – picture opportunity

Hey folks – well folks living in mid-northern latitudes roughly near mine (41.5 N) – circle Monday, December 1 on your calendar, then at 5 pm (or about half an hour after sunset) go out and take a look at the sky to the southwest. You should ses something like this.

Moon, Venus and Jupiter as depicted by Starry Nights software.

Moon, Venus and Jupiter as depicted by Starry Nights software.

You should see a beautiful crescent moon (-10.6), bunched together in a neat little triangle with brilliant Venus (-4.1)and still bright Jupiter (-2). (Of course the moon will look bigger than shown here – the size of the dots for the planets are large to represent their brightness, but they will look like very bright stars.) Should make an easy shot for your digital camera as well – give it a try. The key to such shots is to frame the sky with some nice trees, buildings, or whatever. Take a look at what Hank Walter did here, for example.


But even if you don’t take a picture, having two bright planets join the 3-day-old moon is just fun to see – and pretty. To understand how the planets end up aligned this way, take a look at this earlier post. The moon gets added to the mix because right ont his night it’s lined up between us and the Sun and quite close to the Sun. I checked this in Starry Nights software – the objects are all less than 3 degrees from one another which means you should be able to cover them with your fist held at arms length. (They’ll be roughly two fists above the horizon at 5 pm so you need a clean southwestern horizon.)

If the weather is scrummy (that’s a scientific term) then try Sunday night or Tuesday night – the moon will be much lower Sunday night, and significantly higher Tuesday night – but still fit in the picture.

If anyone gets a picture I’d love to see it and would be happy to post it here.