Ok so we revolve around the sun. At nighttime in January we face away from the sun to see the nighttime sky and stars.

6 months later in July we’re on the opposite side of the sun and now again at nighttime we face away from the sun.

But this direction is now 180 degrees away from the January direction… but the nighttime sky is still the same

How is that possible

  • Dave.@aussie.zone
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    4 days ago

    The nighttime sky is not the same. You see different constellations in summer than you do in winter.

    The stars appear above the horizon about 4 minutes later each day. There are stars at your particular latitude that are always visible (they never set), and they appear to rotate around the celestial pole. If you took note of their positions carefully at a particular time of night, you would see that they end up being 180 degrees opposite where they were 6 months previous.

    If you’re talking about the pattern of stars shifting against the more distant background of stars (star parallax), when the earth is at opposite sides of the sun, this is measurable by observatories for stars within a hundred light years or so but the angular change quickly becomes very small and the universe is very big.

    • Keshara@piefed.blahaj.zone
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      4 days ago

      This resurfaced a really old memory from when I was like 8 or 9 maybe.

      We had a homework assignment (kind of) for school, where we had to go out and pick a star from a spot in our backyards or wherever, and then for each night over 2 weeks we had to track the stars position relative to our position we chose on night 1.

      This was around the late 90s by that point, and I always thought it was pretty cool to get our young imaginations going on the stars beyond ☺️

  • MajorMajormajormajor@lemmy.ca
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    4 days ago

    It’s not the same, you will see different constellations in different seasons.

    Edit: there are constellation map apps you can play around with to get a sense of it. This website lets you do the same.

  • zikzak025@lemmy.world
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    4 days ago

    It depends on where you are on the surface of the Earth. The closer you get to the north/south poles, the more consistent the stars get, because the Earth rotates on a similar axis as its orbit around the sun. Closer to the equator, you’ll get more variation based on season.

    The Earth tilts slightly with the seasons. If you’re far north/south, you’ll see seasonal variety near the horizon, while the stars directly above stay mostly the same. If you’re near the equator, the stars that are directly above will change seasonally, but there will be more consistency on the horizons north/south.

  • the only things that are visible all year around, are circumpolar objects. these are objects that are close to the north or south pole respectively. if you sit on the northern hemisphere, you will not see the southern ones ever. even wirh these you will notice a different orientation if you compare them hour by hour for summer and winter.

  • sbeak@sopuli.xyz
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    3 days ago

    The night time sky is not the same as the constellations above you will look different. It’s difficult to tell, especially if you live somewhere with a lot of light pollution, but the night sky does change. If you are near some place rural where the sky is clear, check it out! It’s pretty neat. Hell, the ancient peoples (Greeks, Chinese, Romans, etc.) wrote mythos relating to how the constellations, perceived as gods, appear and disappear depending on the season.

    Fun fact, there are some constellations that are never visible to those in the northern and southern hemispheres, especially when you go near the poles.

  • spicy pancake@lemmy.zip
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    4 days ago

    I think it has to do with the sheer fuckin scale of how far away most visible stars and other objects are

    like if you look at a street lamp 4 blocks away and move your head 2 mm, it doesn’t really change position that dramatically

    the planets on the other hand are much closer and very much do change positions on a seasonal timescale, to the point where they got used to keep track of the calendar by ancient people

    someone who didn’t major in biochem can probably explain this better haha

    • Karmanopoly@lemmy.worldOP
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      4 days ago

      The constellations visible in January should not be visible in July if we’re literally facing 180 degrees away

      I understand planets will wander, but we shouldn’t see Orion in January and July but we do

      • DomeGuy@lemmy.world
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        4 days ago

        Wherever you are on earth, regardless of season, the only stars you don’t see at night are the ones blocked by that rock you’re standing on.

        ISome of the stars rise or fall under the horizon as the planet spins, and which ones of those you see can and do vary based on the season. These are the ones that the earth (and the sun) block due to the orbit of our planet.

        There will be stars due north or due south that you’ll see all year. This part of the sky isnt blocked by the earth or the sun at all. In fact, if you use a camera with the right hardware to see through the diffuse sunlight that makes the sky seem blue, you could see the same small disk of the sky at any time during the year, regardless of season or time of day.


        Note that the above assumes you’re in one of the temperate bands between the tropics and the polar bands, where sunlight varies throughout the year but every day has a night.

        On the poles you only get one night a year, and it’s always the same stars. And on the equator you need a clear horizon to see the polar stares, while the seasonal constellations will be more or less right overhead.

      • AstralPath@lemmy.ca
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        4 days ago

        I’m at exactly 45° latitude. I wait all year for winter to come so I can observe Orion as its not visible for me in the dead of summer. It does remain visible for a while into spring and fall however.

      • ThatGuy46475@lemmy.world
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        4 days ago

        The constellations are different at different times of year. Scorpio is the scorpion that killed Orion, so they were thrown into different parts of the sky since they don’t get along, and that’s whey Scorpio appears in the summer and Orion appears in the winter.

  • bstix@feddit.dk
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    4 days ago

    I think the easiest way to grasp this is to take (or visualise taking) a basket ball and a tennis ball in each hand and sit in the center of your kitchen.

    Consider the “constallations” in your kitchen: Big sink, Cold Fridge and Hanging Lamp.

    Then try if can you see these from the tennis ball if you hold it in various positions around the basket ball.