Tonight's Super Blue Blood Moon Eclipse May Help Us Find Alien Planets
In case somehow you haven't heard, there's going to be a particularly special moon tonight.
The so-called "super blue blood moon" will see several lunar phenomena stack on top of each other, in a convergence of special events that last took place 150 years ago.
The fact that tonight's moon will be a blue moon isn't all that special—this merely means that, due to the differences between the lunar and Gregorian calendars, tonight will see the second full moon of the month of January. This is a rare event, but not as cool as some other things that will be going on.
What's more interesting is that the moon will be larger in the sky than normal—a so-called "supermoon," as the giant rocky satellite gets to the part of its orbital cycle that is closest to the Earth. We won't be seeing a huge moon, but it'll certainly light up the sky if you happen to be anywhere that doesn't endure constant light pollution.
This event also happens to coincide with a "blood moon", better known among scientists as a lunar eclipse. Tonight, the moon will pass behind the Earth so that it is within our planet's shadow, and instead of appearing white, the moon will look blood red as it is lit by the ambient glow of our own planet, rather than directly by the sun. For anyone who might be standing on the surface of the moon, it'll appear as if the sun has entirely disappeared, but on Earth, all we'll see is a dim, dark red coloring on the moon.
This event is of particular interest to scientists who are looking to learn more about habitable planets, and how they appear when viewed from afar.
While there are plenty of planets out there that look like they might be habitable, we're having a hard time telling whether any of these worlds actually contain oxygen atmospheres and living beings. Scientists theorize that the best way to learn what alien planets look like is to get a better idea of what our own planet might look like to alien observers.
Hence, the stargazing community is eagerly awaiting an ongoing study at Harvard which is studying the moonlight that we see during a blood moon like the one that will appear in our skies tonight. The aim is to find out how this light differs from standard sunlight as a result of passing through our atmosphere.
We know that the light that will reach the moon from Earth is red because our oxygen-rich environment strips away light on certain bluer areas of the color spectrum. Now, scientists are hoping to expand that knowledge to see what else might change while the light is with us. If all goes well, this could help us to be able to better spot the shimmer around distant planets that have their own breathable atmospheres.
It'll be some time before we get the results from this study, but rest assured that the scientists will be paying particularly close attention to the moon tonight as it cuddles up within our shadow.
So while you're enjoying the giant red moon as it sits in the night's sky, bear in mind that there's more going on here than a quirky natural phenomenon. If we get very, very lucky, tonight's super blue blood moon might be the key to finally spotting inhabited alien worlds.