enter image description here

The picture was taken with a smartphone camera at Latitude 48.860045 | Longitude: 2.366202 the 31th of July at 01h07min15s Paris time. On the left is obviously the Moon, and the lower red circle points the point of Latitude: 48.852886 | Longitude: 2.369167. (It's the angel of liberty, place de la Bastille, Paris.)

What does the upper circle point to ?

At the beginning I thought it was Venus, but as far as I remember, it disappears quite early in the evening. I don't think it is Mars : the light reflection on it isn't red enough.

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    $\begingroup$ There is also a google sky map, it is wonderful! You can see the sky with your mobile. $\endgroup$ – peterh - Reinstate Monica Jul 31 '18 at 9:47
  • $\begingroup$ I know I tried on mobile, but typically, if it's Venus or Mars, I will be able to see their positions live. $\endgroup$ – Olorin Jul 31 '18 at 9:58
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    $\begingroup$ Voted up simply because it's one of the very few examples of a question like this where enough quality info is supplied to allow people to make something more than guesses. $\endgroup$ – StephenG Jul 31 '18 at 12:56
  • $\begingroup$ @StephenG Thank you Stephen. It's cheering me up since my question was downvoted one time, and I asked myself then : what do you have to do these days on stackexchange sites not to be downvoted if you're downvoted with a precise and acceptable question. $\endgroup$ – Olorin Jul 31 '18 at 15:13
  • $\begingroup$ It would be better if the down voter explained their issue, although of course they're not required to on SE. $\endgroup$ – StephenG Jul 31 '18 at 15:30

I think it is Mars. Although it's difficult to tell, just looking at the image, but if it were Saturn then you would also be able to see Mars. Mars is much brighter than Saturn at the moment, so if Saturn were visible, Mars would be even brighter. The fact that there is only one bright object (other than the moon) is, I think, conclusive evidence that this must be Mars.

Looking over the city, the large brick building on the Rue St Gille is visible, and the object is visible directly in line with the phone mast on that building. That gives a direction just East of South. Checking with Stellarium at the given time shows Mars at exactly that position, at an azimuth of 171.

  • $\begingroup$ That's plausible except that the OP said that it wasn't red enough to be Mars -- and goodness knows that Mars looks very bright and orange these nights! An argument in favor of Mars is that this is a couple days after Mars and the Moon had a conjunction. You may well be right. $\endgroup$ – Mark Olson Jul 31 '18 at 13:47
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    $\begingroup$ @MarkOlson looking over a city there may be too much local light pollution $\endgroup$ – Carl Witthoft Jul 31 '18 at 15:37
  • $\begingroup$ I've checked on stellarium, using the direction evidence in the photo, and Mars is an exact fit. I've edited to add this to your answer. $\endgroup$ – James K Jul 31 '18 at 15:44
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    $\begingroup$ @Carl Witthoft: You may be right. I just remembered that I have a planetarium program on my iPad. When I set up the place and time it shows the Moon just a bit east of SE and Mars just a bit east of S. Saturn is due SSW. All three are at the same altitude. If we knew the direction of the photo, it would be clearer, but I have to agree that it's Mars. If the circled object was Saturn, Mars would have to be on a line connecting Saturn with the Moon, and there's nothing there. $\endgroup$ – Mark Olson Jul 31 '18 at 15:52
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    $\begingroup$ I've added the second paragraph. I identifed the building visible in your image using google maps. I think it is the brick building on Rue St Gilles. That gives me a direction of the object of about 10 degrees East of South. I then used planeterium software to to simulate the view from the direction given, and Mars is 10 degrees E of S at that time and date. $\endgroup$ – James K Jul 31 '18 at 15:52

At Paris, Jupiter sets at 12:51 am and Saturn sets at 3:37 am. Both are bright and both set in the southwest. At 1:05 AM, Saturn would have been at 15 degrees elevation in the SSW. The Moon would have been to the SW at about the same altitude.

So it looks like this was Saturn. (Someone with a full-up planetarium program could confirm.)


![enter image description here

Here's a Stellarium simulation of the Paris sky at the time you indicate. Mars and the Moon are at about the same altitude, as in your photo, while Saturn is further to the west, a little higher, and two or three magnitudes dimmer.

  • $\begingroup$ Check the time zone, I think you might be an hour out. $\endgroup$ – James K Jul 31 '18 at 18:14
  • $\begingroup$ @JamesK Huh, I didn't realize Paris was on UTC+2 in the summer. The extra hour actually doesn't change the image very much, though. $\endgroup$ – rob Jul 31 '18 at 19:35

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