Yes, our little Moon. "Imagine taking a pile of metal five times larger than the Big Island of Hawaii and burying it underground. That's roughly how much unexpected mass we detected," lead author Dr. Peter James, assistant professor of planetary geophysics at Baylor University, said in a statement.
https://www.foxnews.com/science/mysterious-mass-discovered-moon


There's a huge mass embedded in the center of the moon, and astronomers aren't sure what it is
https://www.cnn.com/2019/06/11/us/moon-mass-crater-mystery-unexplained-trnd/index.html

Here is something you may not know about the Moon: Earth's clingy best friend is also the site of one of the largest-known impact craters in our entire solar system. Essentially, something caused a giant hole on the Moon billions of years ago, and astronomers have just discovered that there's something big -- really big -- buried underneath the surface.

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Its the molten iron core resulting from the collision between Earth and the Planet that hit us (probably the size of Mars). Perhaps it is solid since I don't think the Moon has a Magnetic field.

Mass concentrations ("mass-cons") have long been known to exist on the Moon.

That is what I thought. Thanks William.

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Gotta say this, maybe it's the "obelisk" from 2001.

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Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.