• Question: During an eclipse, is the dark side of the moon actually the light side of the moon?

    Asked by anon-257942 on 25 Jun 2020.
    • Photo: James Smallcombe

      James Smallcombe answered on 25 Jun 2020:

      Yes in a solar eclipse the “dark side” of the moon would be facing the sun, and so lit up. But the “dark side” is also lit by the sun during normal parts of its monthly orbit of the earth when the moon is closer to the sun than the earth (think any time you have seen the moon during the day). “Dark side of the moon” means it faces away from the earth, this is because the moon spins on its axis at exactly the same rate it orbits the earth.

    • Photo: Roan Haggar

      Roan Haggar answered on 26 Jun 2020:

      There isn’t really a ‘dark side’ of the moon, as all parts of the moon are sometimes dark and sometimes light. Usually when people say this, they mean the ‘far side’. The same side of the moon (the ‘near side’) is always facing towards Earth, and the other side (the ‘far side’) points away.
      —
      When we see a full moon, it’s because the near side is being lit up by the Sun, so we can see it. Instead, if the far side is lit up by the Sun then we get a ‘new moon’, meaning that we can’t see the moon from Earth, because the bit facing towards us is dark.
      —
      This is also what happens during a solar eclipse. So yes, the far side of the moon is the light side during an eclipse. Hope this helps!

Comments

  • Photo: anon-257942

    anon-257942 commented on :

    Thanks. Can you also tell me how we can see the moon, rather than it just being a shadow. Does the light shine through the moon?

    • Photo: NuclearJames

      NuclearJames commented on :

      During parts of the month when the moon is further away from the sun than the earth (can see moon at night) but is not directly behind the earth (so a bit to the side) sunlight will pass the earth and hit the moon and then reflect, and we see this reflected light.
      Depending on the exact position of the earth/moon/sun we see different parts of the moon being illuminated and this leads to the different phases of the moon; full moon, crescent moon, etc.