There’s been lots of exciting space news, starting with today’s announcement that the Event Horizon Telescope has successfully made the first image of the black hole at the center of our own Milky Way Galaxy:
You can read the press release about the black hole image here. Meanwhile, for today’s email, I want to focus on something you can see with your own eyes: Sunday night’s lunar eclipse. Like any lunar eclipse, this one will be visible (at least part of it) to more than half the world, including in the Americas, Europe, and Africa. It is especially easy for those of us in the contiguous USA, since it will be visible at or shortly after sunset, meaning you don’t need to get up at some crazy hour of the night! A few notes and details:
The noticeable part of the lunar eclipse begins when the Moon first enters Earth’s full shadow (umbra). This will be on Sunday night (May 15) at 10:28pm eastern time, which means 9:28pm central, 8:28pm mountain, and 7:28pm pacific (but for the west coast, the Moon will not yet have risen, so watch starting at moonrise).
It’s worth watching the entire eclipse, but if you only want to watch for a short time, the best part to watch is the onset of totality, which will occur at 11:29pm eastern (10:29pm central, 9:29pm mountain, 8:29pm pacific). Start watching at least about 15 minutes before totality, so you can see the change as the shadow moves across the face of the Moon. Be sure to note the curvature of the shadow, which is absolute proof that Earth is round! (Teachers: see this free section for detail and classroom activities on how to prove that Earth is round.)
You can of course watch the lunar eclipse on your own, but it may be more fun to go to an eclipse watching event. Check your local science center, planetarium, astronomy club, or university to see if they have anything planned. For example, those of you in my hometown of Boulder, CO, can watch the eclipse (outside) at Fiske Planetarium.
Now, about the names for this eclipse you may hear in the news, which is being called a “super blood moon” eclipse:
The “super moon” designation applies to any full moon that happens to occur when the Moon is in the part of its orbit that brings it closest to Earth (that is, near perigee). The term is loosely defined, but you can probably see the idea: just like bringing your thumb closer to your eye makes it look bigger (in angular size), the Moon looks bigger if it is full when it is closer to Earth. So this particular lunar eclipse is “super” because it is happening when the Moon is relatively close to Earth.
“Blood moon” is a term sometimes used to describe the Moon during a lunar eclipse, when the Moon turns noticeably red in color. However, it has absolutely nothing to do with blood. To understand the real reason why the Moon looks red during a lunar eclipse, consider the view of an observer on the eclipsed Moon: When looking at Earth, the observer on the Moon would see Earth’s night side (which will be blocking the view of the Sun behind it) surrounded by the reddish glow of all the sunrises and sunsets occurring on Earth at that moment; it is this reddish light that illuminates the Moon during the eclipse.
Get Ready for the 2023 and 2024 USA Solar Eclipses!
Lunar eclipses are cool, but far more spectacular are solar eclipses. Many of you will remember the 2017 total solar eclipse, and it’s time to start thinking about two great solar eclipses coming to the USA:
October 14, 2023: An annular solar eclipse. An annular eclipse occurs when the Moon is relatively far from Earth in its orbit, so that it doesn’t quite cover the Sun during its maximum. We therefore will see a ring (or “annulus”) of sunlight surrounding the eclipsed Sun. This means it won’t get completely dark, and you’ll need to wear eclipse glasses throughout the event, but it is still well worth seeing.
April 8, 2024: Total solar eclipse! With more than 4 minutes of totality in some places on the center line. Maps for both eclipses (courtesy of Micheal Zeiler at Great American Eclipse):
Note: You should try to get to the paths of annularity/totality if at all possible, but the rest of the contiguous US (and Canada, Mexico, and more) will have a partial solar eclipse in both cases.
Also: Between now and these events, there will also be a total solar eclipse visible in the western Pacific on April 20, 2023; use the free Totality app for maps and viewing details.
The best way to prepare and learn more about these upcoming eclipses is with the free app “Totality by Big Kid Science.” Download our latest version from your app store now. And…
Please watch for my new book, Totality! An Eclipse Guide in Rhyme and Science. Official publication date is Sept. 14, 2022 (exactly 13 months ahead of the 2023 annular eclipse), but the books are currently en route to the warehouse, so they will likely be available by early summer. More info about the book will be posted here. Note that the book comes with two pairs of eclipse glasses.
Teachers/Educators: Jeff’s School Visits to Resume
Now that Covid restrictions have eased, I am resuming my visit program for schools, universities, and the public. In particular:
Colorado Elementary Schools: Contact me about scheduling a free school visit for the coming academic year, especially if you are in the Boulder/Denver area.
Nationwide schools, universities, science centers: I will also be resuming my “free visit program,” in which I will travel to your location at my own expense if you can put together a busy program of events for me. More information here (though note that I’ll be updating details to put more focus on the upcoming eclipses).
New Editions of Life in the Universe, Using and Understanding Mathematics
