Is it possible for the Moon & a pair of planets to conjunct as smiley face?

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Discussion Overview

The discussion revolves around the possibility of the Moon and a pair of planets (Jupiter and Venus) aligning in the sky to form a smiley face shape. Participants explore the conditions necessary for such an alignment, considering factors like the Ecliptic, the size of the Moon, and the visibility of the planets.

Discussion Character

  • Exploratory, Technical explanation, Debate/contested

Main Points Raised

  • Some participants note that for the Moon to be positioned between the planets and the Sun, it must align along the Ecliptic, where the planets are typically found.
  • Others argue that the Moon's width is only about 1/4 degree, which may allow for some flexibility in positioning.
  • A participant expresses skepticism about the feasibility of the alignment on a specific date, citing resources that show the Moon and planets are not in proximity.
  • Some suggest that while a perfect smiley face may be impossible, an approximate alignment could be considered if the planets are close enough.
  • Concerns are raised about the visibility of the planets during dawn or dusk when the Moon is present, as the Sun's position would affect their appearance.
  • Participants discuss the potential for the Moon to occult the planets, leading to a temporary smiley face effect as they emerge from behind the Moon.
  • There is mention of past events where similar alignments occurred, with varying visibility depending on geographic location and time of observation.

Areas of Agreement / Disagreement

Participants express differing views on the feasibility of the Moon and planets forming a smiley face, with no consensus reached on whether such an event is possible or if it has occurred in the past.

Contextual Notes

Some participants highlight limitations in their observations based on the specific date and location, as well as discrepancies in data from different astronomical resources.

swampwiz
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I was reading this:

http://www.physics-astronomy.com/2020/04/set-your-alarm-jupiter-venus-and-moon.html

It seems that for this to happen the Moon would need to be in-between the pair of planets and the Sun - but the Sun's path defines the Ecliptic, and the bright planets are all very close to the Ecliptic, certainly closer than the size of the Moon.
 
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No reason why it's not possible.

Moon is only 1/4 degree wide.

1587245049913.png
 
After checking a couple of resources (Celestia, World Wide Telescope, and Horizons web site), I've come to the conclusion that this supposed meeting up isn't going to happen. On that day, none of these bodies are even in the same part of the sky according to any of them. The Moon isn't even that much of a crescent. Now on May 16, 2010, the Moon was a thin crescent, and Venus was also in the right part of the sky, (both in Taurus) but no Jupiter(It was in Pisces). I think this might be another of those "Mars will appear as large as the Moon" things.
 
Hmmm...

Given the 'classic" smiley face..

1587250868997.png


It appears impossible because the planets would be behind the moon.

If you instead want to say, "Yeahbut I'm looking for an approximate smiley face, I think you need to tell us how close is close enough.
 
How about close enough to entice astro-virgins off the couch to go out and gaze at the Heavens, possibly inspiring new hobbyists?
 
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Assume a spherical smiley face...there is a joke here somewhere but I seem to have lost it.
It is just the right time of year here...no bugs and maybe a sweatshirt...
 
DaveC426913 said:
Fourmilab's virtual telescope suggests Jupiter and Venus are nearby, though a pretty lopsided smiley.

http://www.fourmilab.ch/cgi-bin/Yourtel

View attachment 260921
Interesting. World Wide Telescope shows this for the relative positions of Jupiter and Venus for this date
( arrows are sight-line from earth).
system.png

Celestia shows this Looking over the Earth towards the Moon, neither Jupiter or Venus are shown close, though Neptune is in the picture.
moon2.png


You have to rotate the view quite a bit to see Venus, and by then the Moon is well off to the side of its orbit in relation (white dot on right side of red ellipse over by Mercury in the image).
moon1.png


Going by the Dec and RA given by the Horizons site, these are the positions of the three on that date:
sky.png

While the Moon and Jupiter look close in this image, it is a 360 degree wrap- around, and they are over 45 degree apart in the sky. Venus is over 90 degrees away from the Moon (which agrees with Celestia)
I wonder why the discrepancy from what you found?
 
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Janus said:
I wonder why the discrepancy from what you found?
Dunno. But I'd trust a virtual telescope with a view of the sky from Earth over - er - spitballing it from a sim of the Solar System, but YMMV.

[EDIT]
I've changed my mind.
'In the sky' seems to be giving me similar results to yours.
https://in-the-sky.org/whatsup.php?year=2020&month=4&day=18&town=6167865

I'm wondering if this is a hoax - that it occurred on that date in some other year and they've just updated the year.
 
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  • #10
DaveC426913 said:
No reason why it's not possible.

Moon is only 1/4 degree wide.

View attachment 260920
But the planets would need to be that much off of the Ecliptic so that the Sun would be on the other side of the Moon from the planets.

EDIT: OK, it looks like Venus & Jupiter are 3.4 & 1.3 degrees off the Ecliptic plane, so the Moon could just barely nudge itself in between, but it would still be "daytime" dawn/dusk so the planets would not be visible, and the terminator on the Moon would almost completely encompass the whole disk.
 
  • #11
DaveC426913 said:
Moon is only 1/4 degree wide.
A minor point, but to be accurate the moon is 1/2 a degree wide.
 
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  • #12
swampwiz said:
But the planets would need to be that much off of the Ecliptic so that the Sun would be on the other side of the Moon from the planets.

EDIT: OK, it looks like Venus & Jupiter are 3.4 & 1.3 degrees off the Ecliptic plane, so the Moon could just barely nudge itself in between, but it would still be "daytime" dawn/dusk so the planets would not be visible, and the terminator on the Moon would almost completely encompass the whole disk.
On may 16, 2010, this is what you would have seen from Perth, Australia (Sun below horizon).
MOON_VENUS.png


And on Dec 1, 2008, you could have seen this:

smiley.png


Not exactly the image being promoted, But I think we can be pretty sure that this recent one is a hoax.
 
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  • #13
Janus said:
On may 16, 2010, this is what you would have seen from Perth, Australia (Sun below horizon).
View attachment 260968

And on Dec 1, 2008, you could have seen this:

View attachment 260969

Not exactly the image being promoted, But I think we can be pretty sure that this recent one is a hoax.
I hadn't thought of a pair of planets being at the same "hour angle" along the Ecliptic (whatever that is called) with the separation due to the angle of their respective orbital plane with respect to the Ecliptic. With that as a possibility, it's no problem for the Moon to be the proper smiley position. I could see a very good popping up every once in a long while!
 
  • #14
sandy stone said:
A minor point, but to be accurate the moon is 1/2 a degree wide.
Dang it! I knew that, and overrode my first answer. (Google said radius is .26. Oops.)
 
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  • #15
swampwiz said:
It seems that for this to happen the Moon would need to be in-between the pair of planets and the Sun - but the Sun's path defines the Ecliptic, and the bright planets are all very close to the Ecliptic, certainly closer than the size of the Moon.

On the night of 1 December 2008, there was a frown. Below is a screen shot for this event from the Stellarium app on my laptop.

1587336622996.png
 
  • #16
Vanadium 50 said:
Hmmm...

Given the 'classic" smiley face..

View attachment 260922

It appears impossible because the planets would be behind the moon.

If you instead want to say, "Yeahbut I'm looking for an approximate smiley face, I think you need to tell us how close is close enough.

Is it possible for a Moon and two planet smiley face to wink as Moon occults two planets simultaneously and then both planets emerge from dark side of Moon, not quite simultaneously?
 
  • #17
George Jones said:
On the night of 1 December 2008, there was a frown. Below is a screen shot for this event from the Stellarium app on my laptop.

View attachment 260991
It depends on where in the world you viewed it from. The Moon moves at about 1/2 degree per hour relative to the stars. Thus the time of day you are viewing it on that particular day will determine its relative position with respect to Jupiter and Venus. Where you are in the world will determine what you would see while the Moon is above the horizon and the Sun below it. So in Argentina on that date sometime after sunset, you would see something like your image. However, just after sunset in western Australia, You would see that arrangement shown in my image. This is because of the time difference between sunset in Argentina and in Australia and how much the Moon moves relative to Jupiter and Venus in the intervening hrs.
 

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