You don’t need an astronomer to tell you that the Sun is now high and strong. The summer solstice is coming up on Tuesday June 21 about an hour before sunrise, which explains why we already feel the year’s most powerful sunlight. But there is more to the story.
The full Moon always hovers opposite the Sun so that this Tuesday’s full Moon on June 14 is a disk that is basically the Sun in reverse. It rises just as the Sun sets. Since the Sun is highest at around 1 p.m., the full moon reaches its highest point at 1 a.m. The Sun hovers at the highest-up portion of the zodiac, on the Taurus-Gemini boundary line, so this coming full Moon sits at the antithesis of that, the zodiac’s lowest part which is in Sagittarius. And it actually manages to creep even lower down than that, since it’s nearing its ultimate nadir thanks to its orbit suffering an 18.6-year wobble that periodically carries it to extreme celestial positions. That means this Tuesday night even when the full Moon reaches its loftiest position of the night at 1 a.m. it will barely be 20 degrees above the southern horizon. We will see the lowest full Moon of the past several years.
But it so happens that very position in Sagittarius happens to be where our galaxy’s famous supermassive black hole is located. It made headlines recently because the first-ever photograph of it has been widely publicized. This is a region with the mass of four-million Suns all crushed into a tiny volume that astronomers call Sagittarius A-star. It lies at the center of our Galaxy.
This means that everything in the sky revolves around that spot where Tuesday’s full moon will be hovering, or to precise, 25,000 light years behind the Moon. There is goodly evidence that every galaxy has a supermassive black hole at its center so that ours is not only unexceptional but actually rather lightweight compared to most others.
Enough nitpicking. The main take away is that next Tuesday night about an hour after midnight we will see the lowest full Moon of the year floating in the spot precisely opposite the Sun, a place that also marks the supermassive black hole at the heart of our Milky Way Galaxy. If that’s not enough of a passing idea to be worthy of flitting through your mind Tuesday evening, come back next week and we’ll try to do better.