Starship Asterisk*

A Mercury Transit Sequence

Explanation: Tomorrow -- Monday -- Mercury will cross the face of the Sun, as seen from Earth. Called a transit, the last time this happened was in 2016. Because the plane of Mercury's orbit is not exactly coincident with the plane of Earth's orbit, Mercury usually appears to pass over or under the Sun. The featured time-lapse sequence, superimposed on a single frame, was taken from a balcony in Belgium shows the entire transit of 2003 May 7. That solar crossing lasted over five hours, so that the above 23 images were taken roughly 15 minutes apart. The north pole of the Sun, the Earth's orbit, and Mercury's orbit, although all different, all occur in directions slightly above the left of the image. Near the center and on the far right, sunspots are visible. After Monday, the next transit of Mercury will occur in 2032.

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When I first go to APOD, the image is 90° off so it looks like Mercury's orbit is on a vertical plane. It's the correct horizontal plane when I click on the image, though.

futurejohn wrote: ↑Sun Nov 10, 2019 12:13 pm When I first go to APOD, the image is 90° off so it looks like Mercury's orbit is on a vertical plane. It's the correct horizontal plane when I click on the image, though.

Thanks for that insight. I often don't choose the 'click-on' feature, and I was a bit confused today until I saw your post. I wish they'd have drawn Earth's orbit in for those of my ilk lol...

Ahh; Mercury! You're a real Hottie!!

Both images are off. According to NASA's illustration the transit would look more like the first one ascending from left to right, but not as steep and a bit closer to the Sun's centre this time. That's because Mercury always ascends in the orbit in November and descends in May. So the second picture was taken in May.

11/11/2019 I just watched a replay of the full transit on the NASA site. Mercury sure looks insignificant against the Sun.