On this week's wrap-up of the Space.com forums, we chat about UFOs. We also get excited about some interesting facts concerning the moon and wonder about parallel universes. But first, we test our knowledge of the sun with a fun quiz to celebrate this week's "ring of fire" solar eclipse!
Test your solar knowledge!
Let us know what you think of the sun, UFOs, science fiction and more in our Space.com Forums here!
Ah, yes, the sun. Despite all of the intriguing factoids we’ve come to know, there's still so much to learn about our solar system's heat source.
Still, you’d be surprised how much scientists and astronomers have already discovered. Test your own knowledge about our very own yellow star with this fun quiz, courtesy of Helio.
'Ring of fire' solar eclipse 2021: See amazing photos from stargazers
Learning about the moon
An equally intriguing cosmic object, the moon is the Earth's one and only natural satellite. However, did you know that there are several theories as to how the moon originally formed? One such theory is that a piece of the primitive molten Earth was torn away after a massive collision long ago.
As you can imagine, this community of space enthusiasts is enjoying the moon's time in the limelight:
Our moon seems to have a "special" attraction for our species. It actually seems a comfort to notice the moon even at different phases. It is especially spectacular when the full moon rises and perspective magnifies it's presence on the horizon. I'm heartened that the moon is "taking it's time" retreating from the Earth; otherwise, I would miss it and we all would be poorer for the absence. - sam85geo
I note this in the article about the Moon. "The pull of the moon is also slowing the Earth's rotation, an effect known as tidal braking, which increases the length of our day by 2.3 milliseconds per century. The energy that Earth loses is picked up by the moon, increasing its distance from the Earth, which means the moon gets farther away by 1.5 inches (3.8 centimeters) annually." My observation. This rate of expansion by the Moon from Earth works out to be about 1.2 x 10^-7 cm/s. In the BB model, H0 = 69 km/s/Mpc works out to about 2.236 x 10^-18 cm/s/cm.
Q:Which rate of expansion is most secure based upon measurements? My answer the Moon's rate :) - rod
Do they exist?
Here's another story that had the community talking this week. We're presented with the question, "do parallel universes even exist?” As you can imagine, there is a ton of room for discussion here. Here's a taster of the conversation:
One small item of contradiction to the illustrations of bubble universes, as well as part of the text. It's called "boundarylessness". I take it to mean you can't bump your face into a wall of bubble such as the illustrations and a part of the text suggests.
"Boundarylessness", to me means that bubble universes offset. They overlay and inlay into one another (of course not exactly except for those infinities of absolute duplicates at infinite distances apart; in which case there is no difference in and between them from an absolute of just "one and one only"), thus an infinitely flat (infinitely flat (infinite in depth of plane(s), infinite in extent -- "dimensionless point"), smooth, non-local, non-relative, 'naked singularity' of 'Space-verse' Big Universe (U). - Atlan0101
With the recent transparency around dealings with UFOs, you wouldn’t be blamed for getting a bit excited. And yet, recent reports suggest that there is no evidence that alien objects have ever made their way to Earth. Here is just a bit of what the community had to say:
Sure, the popular conception is that if we can’t figure it out, they must be E.T.s, but, from a correctly scientific point of view, if we don’t have physical evidence that they are extraterrestrial, we don’t conjecture. Seems more likely photo equipment artifacts. - Pogo
Consider that the U.S. is using denial as an artifact to have adversaries believe the opposite. The Report is just a continuation of the UFO spoof/delusion/hysteria that has spawned an entire industry and culture. - sam85geo
Still, what are they? Why can't we see the clear and up close pictures? Is there some kind of proof in the pictures? - o5dkelly
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