Did J.K. Rowling ever explain how Harry Potter could see Orion during the O.W.L. Examination?

Question

How was Harry able to see the constellation, Orion, in the middle of summer in the far northern hemisphere? Did they use magic?

Answer 1

I believe this is a mistake by Rowling

The O.W.L. exams are taken in June:

...June had arrived, but to the fifth years this meant only one thing: Their O.W.L.s were upon them at last.
_{Harry Potter and the Order of the Phoenix - Chapter 31: O.W.L.s}

When Harry goes to take his Astronomy exam, it is 11pm:

When they reached the top of the Astronomy Tower at eleven o’clock they found a perfect night for stargazing
_{Harry Potter and the Order of the Phoenix - Chapter 31: O.W.L.s}

The entries they make on their charts are implied to be what they are currently observing:

Professors Marchbanks and Tofty strolled among them, watching as they entered the precise positions of the stars and planets they were observing.
_{Harry Potter and the Order of the Phoenix - Chapter 31: O.W.L.s}

I believe this quote suggests Harry was previously looking at Orion, before making an adjustment to look at Venus:

As Harry completed the constellation Orion on his chart, however, the front doors of the castle opened directly below the parapet where he was standing, so that light spilled down the stone steps a little way across the lawn. Harry glanced down as he made a slight adjustment to the position of his telescope and saw five or six elongated shadows moving over the brightly lit grass before the doors swung shut and the lawn became a sea of darkness once more.
Harry put his eye back to his telescope and refocused it, now examining Venus.
_{Harry Potter and the Order of the Phoenix - Chapter 31: O.W.L.s}

He 'completed the constellation Orion on his chart', makes 'a slight adjustment to the position of his telescope' before 'now examining Venus'. I think this string of events heavily implies he was actually looking at Orion.

Using a planisphere, I can confirm that the constellation Orion is not visible in the June sky in the Northern Hemisphere at 11pm. In fact, it doesn't appear in the sky at all in the hours that it would be dark in Scotland in June, from around 10pm to 5am. From quotes, his exam seems to take around 2 hours, but this is beside the point - his exam could have lasted the entire night and he still wouldn't have been able to see it. There are no quotes saying magic is used for observations during the exam, so I think it's safe to rule that out. It is simply a mistake on the author's part.

I can't say this with 100% confidence, but I've a suspicion that he couldn't see Venus then either given he's observing it after 11pm, and a June 1996 astronomy almanac makes no mention of it.

Answer 2

As @user14094230 already added in his comment, the exact quote from the book is:

As Harry completed the constellation Orion on his chart, (...)

The most probable reason for that passage is that JKR sucks at astronomy.

But trying to find an in-universe answer, I would say that Harry simply made an error on his star chart. He was just a student taking an exam, from which he received "A" note (the lowest of pass grades). Astronomy has never been of Harry's high interest. It's likely he confused some other constellation with Orion, but most of his star chart was correct.

Answer 3

I mean, JKR also doesn't understand that after the spring equinox, the days are longer the further North you are. In Deathly Hallows, when they're at shell cottage and Harry reads Voldemort's mind, he sees Hogsmeade which is "still dark, because it was so much further North" (quoting from memory, so probs not exact), but it's Easter, which is after the spring equinox, so it gets light earlier further North. In other words, JKR generally doesn't understand that stuff in the sky changes depending on the time of year.