Week of June 4-10, 2017

At least once a year we hear about the supermoon, when the full moon appears largest in our sky.

But why do we rarely hear about the full moon appearing at its smallest? Why doesn't this make the headlines? Why don't we get inflated news reports about this?

Well, get ready. In the often-overblown style we hear on TV or read on the internet, let me offer the following: If you step outdoors on the evening of Friday, June 9, and look skyward, you will see a spectacular sight that few have ever seen: the Mini-Moon!

Of course, this is total baloney, just as all the supermoon hype is. Neither is all that rare, and neither is all that noticeable.

It is true that the moon changes its apparent size in our sky. That's because it doesn't remain at a constant distance from us as it would if it would if it were to orbit the Earth in a circular path. Instead, it travels along an elliptical path and, therefore, alters its distance and apparent size throughout its monthly orbit.

Fortunately, this change is not huge because, without the moon's relatively constant gravitational pull, the tides would never have made it possible for life to emerge from the seas eons ago.

On June 8, the full moon will lie near apogee, its farthest point from Earth, and on the following night, it will appear as the smallest full moon of 2017. The exact time of apogee occurs at 3 p.m. PDT (6 p.m. EDT) on June 8, when the moon will lie 252,526 miles from us.

So will you actually notice that Friday's full moon appears smaller than average - as a mini-moon? Perhaps, but only if you've convinced yourself in advance that it should appear smaller. Otherwise I suspect it won't be obvious to the average stargazer.

Part of the reason is that our memory of such things is not very reliable; in fact, only experienced moon watchers might be able to detect this mere 5 percent reduction from its average size.

Now, while this is a relatively minor difference, we can easily see it by comparing two full moon photographs: one taken at apogee and another at perigee (its closest point to Earth). You can easily create such a photo comparison for yourself.

Use a camera with a long telephoto lens (300 to 400mm will do nicely), and set your camera to manual mode and ISO 200. Try 1/250 second at f-stop 8 to start, but try some other exposures to make sure that something turns out well.

Capture one image on June 9 and shoot another on Dec. 3 — the night of the closest full moon of this year — using exactly the same settings. By comparing these two images side by side, you'll discover that this month's full moon appears slightly smaller than that of December — only about 12.5 percent — which is probably not enough for beginning sky watchers to notice easily with the unaided eye but more than enough for your photos to show a significant difference.

Whether or not you can notice a difference, it should still be fun to get out at dusk on Friday to check it out!

Check out this week's mini-moon.

Visit Dennis Mammana at www.dennismammana.com. To read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate website at www.creators.com.