0
$\begingroup$

A few weeks ago, I asked the same question about a bright object that I observed, initially thinking it wasn't Venus, but was told that it actually was Venus. Oops, fair enough. Here's another bright object that I observed earlier tonight, which I more strongly believe is something that isn't Venus, and I will articulate why. I'm a computer nerd by trade, but a complete amateur at making astronomical observations, so perhaps my deduction is incorrect and it's that sneaky bugger Venus again. In that case, please explain to me where I erred in my logic, and preferably explain to me how I can investigate and verify my own observations using the standard software that one might use.

photo of the bright spot in the sky while facing south

The object is the dot at the very top of the photo. Here are the parameters of that observation...

  • Time: 1:45am EST(-0400) on 11/2/2023
  • GPS Location: (40.733117,-73.871273)
  • Orientation: facing due south
  • ~60 degrees up from the horizon
  • ~15 degrees to the right/clockwise from orientation
  • Moon phase: waxing gibbous, ~77℅

I mention the moon also, because it isn't too far in the sky from this (apparently stationary) object, and it is relevant to my chain of logic.

Given that it is the middle of the night, and the moon is about 75% full, that places the sun roughly "behind" earth, with respect to the position of the moon. Facing north and looking at the ground, the illumunation of the moon's surface suggests the sun is roughly located in the northwest quadrant of the ground's plane. Now, Venus orbits between the earth and the sun... How the heck can Venus get so high in the sky, so close to the moon, and for that matter, how can the earth apparently get between Venus and the sun??

Assuming that it's not Venus, what exactly is it? And if I have misidentified Venus again, where did my logic go wrong?

$\endgroup$
3
  • 2
    $\begingroup$ As stated in a comment to your earlier question: If it's basically stationary in the sky, it's really unlikely to be a satellite. "What astronomical object did I see" questions are a better fit for astronomy stack exchange. Also, you can most likely figure this stuff out for yourself at heavens-above.com $\endgroup$ Nov 2, 2023 at 12:24
  • $\begingroup$ @Organic Marble - agreed that normally this type of question is better suited for Astronomy Stack Exchange. I think the possible exception here is that the OP is noticing some really bright objects in the sky, which are so bright because they are relatively close to Earth, making them very naked eye visible. These three planets (Venus, Jupiter, Mars) are the most feasible at least distance wise for humans to travel to. I think it is sort of interesting to relate their easy visibility to our ability to explore them. Sort of like looking up at the Moon and realizing that people have walked on it $\endgroup$ Nov 2, 2023 at 12:51
  • 1
    $\begingroup$ Note that there are plenty of smartphone apps which will show you the position of lots of celestial bodies, taking into account time and date, location and orientation, so you just need to “point at” that shiny thing to discover what it is (and see where Venus is). That should help you a lot. $\endgroup$
    – jcaron
    Nov 5, 2023 at 14:54

2 Answers 2

5
$\begingroup$

Basically, Venus can't be in that position. You're looking at Jupiter, which is typically the second-brightest planet in Earth's sky, and outshines any of the non-sun stars under non-nova circumstances.

Source: Opened up Stellarium Web (https://stellarium-web.org/), set the time to 1:45 AM, (and my default latitude is about the same as yours), and looked in the south direction.

$\endgroup$
2
  • $\begingroup$ I concur: Jupiter. Another source is timeddate.com, where I have preselected the OP's position (Queens, NY). Select Jupiter, adjust the time to 1:45 AM on November 2, and voila. $\endgroup$ Nov 2, 2023 at 11:36
  • $\begingroup$ "So is it Venus or a satellite?" In my intense focus, I nearly forgot that there were other options/objects to choose from. I feel stupid once again. Excellent answers BTW, I'll check out Stellarium! $\endgroup$
    – Bigbio2002
    Nov 2, 2023 at 21:18
2
$\begingroup$

As mentioned in another answer here, you were looking at the planet Jupiter. The reason that it seemed so bright is because you were looking at Jupiter one day before its annual opposition, which occurs this year on November 3rd.

Jupiter is very far from the Sun at nearly 500 million miles (800 km). Earth, being much closer in its orbit around the Sun, passes "underneath" Jupiter about once a year, which makes Jupiter closer to Earth and much brighter for a few weeks before and after opposition. During opposition Jupiter can shine as bright as magnitude -2.9 (lower numbers are brighter). Not quite as bright as Venus which can get to -4.6, but brighter than Sirius which at -1.5 is the brightest star in the Sky. During the rest of the year Jupiter is not quite as bright as it is right now, but it can still be easily seen if you know where to look for it.

Mars also reaches a similar brightness during its opposition. However since Mars is a bit closer to Earth we tend to chase each other around the Sun, so Mars opposition occurs only every 26 months. Which is why space probes (and eventually people) can only travel to and from Mars for a brief period about every two and a half years. The next Mars opposition will be on January 16th, 2025.

While Jupiter is closer to Earth it's a great time to view it with binoculars as you can also observe four of Jupiter's moons, Io, Europa, Ganymede, and Callisto. They will look like little stars lined up near Jupiter. Any particular night they will be arranged differently around Jupiter and you won't always see all four, but typically you will get a view in your binoculars similar to this:

Jupiter and Moons
Jupiter and moons (author: Coomie, Astronomy Stack Exchange)

$\endgroup$
4
  • 1
    $\begingroup$ @Bigbio2002 In general, if you see a bright dot in the sky that isn't apparently moving, it's almost always Venus, Jupiter, or Saturn. They can all be shockingly bright under the right circumstances. $\endgroup$ Nov 2, 2023 at 15:31
  • $\begingroup$ Because of its much greater distance and slightly smaller size than Jupiter, Saturn doesn't get as bright as the others, reaching about -0.5 at its maximum. Even that level of brightness doesn't happen every year as it also depends on the orientation of its rings. Still it's usually bright enough to stand out. Interestingly the lower apparent magnitude happens to correspond with accessibility, as Saturn or its moons likely won't be visited by astronauts until after Jupiter. Mercury meanwhile is bright, but harder to see because it is close to the Sun, which also makes it difficult to visit. $\endgroup$ Nov 2, 2023 at 16:31
  • 2
    $\begingroup$ Yep. That's why Saturn is only the third candidate -- but in my own experience, it can be bright enough to be startling, especially if you have moderate to heavy light pollution that blanks out most stars. I've definitely had times when I looked up and went "Wait, Jupiter's over THERE, so what's THAT?" and had to pull up Stellarium to check. $\endgroup$ Nov 2, 2023 at 16:34
  • $\begingroup$ @DarthPseudonym - I agree that "mid-year" Saturn is often indistinguishable from mid-year Jupiter, and is quite capable of standing out in normal (i.e. light polluted) skies. It just doesn't ever seem to reach the "is that an airplane?" level of brightness that the other three can. $\endgroup$ Nov 2, 2023 at 17:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.