There is a bizarre rocky landscape, well hidden from our prying eyes, in the secretive shadows under the oceans of our Earth. Here, in this strange and alien domain, it is always as dark as midnight. Thin, tall towers of craggy rock emit billows of black smoke from their peaks, while all around the towers stand a weird, wavy multitude of red-and-white, tube-like organisms--that have no eyes, no intestines, and no mouth. These 3-foot-long tubeworms derive their energy from Earth itself, and not from the light of our nearby Sun--a feat that most biologists did not believe possible until these wormish creatures were discovered back in 2001. The extremely hot, superheated black water, billowing out from the hydrothermal vents erupting on Earth's seafloor, provides high-energy chemicals that sustain the tubeworms, as well as other weird organisms that apparently thrive in this very improbable habitat.
GRAIL has also generated new maps showing lunar crustal thickness. These maps have managed to uncover still more large impact basins on the near-side hemisphere of Earth's Moon--revealing that there are fewer such basins on the far-side, which is the side that is always turned away from Earth. This observation begs the question: How could this be if both hemispheres were on the receiving end of the same number of crashing, impacting, crater-excavating projectiles? According to GRAIL data, the answer to this riddle is that most of the volcanic eruptions on Earth's Moon occurred on its near-side hemisphere.
When Jupiter was born along with the rest of our Solar System, approximately 4.56 billion years ago, it twinkled like a star. The energy that it emitted--as a result of tumbling surrounding material--made Jupiter's interior searing-hot. In fact, the larger Jupiter grew, the hotter it became. At long last, when the material that it had drawn in from the whirling, swirling surrounding protoplanetary accretion disk--made up of nurturing dust and gas--was depleted, Jupiter may well have attained the enormous diameter of over 10 times what it has today. It also may have reached a truly toasty central temperature of about 50,000 Kelvin. During that long ago era, Jupiter twinkled, glittered, and sparkled like a little star, shining ferociously with a fire that was approximately 1% that of our much more brilliant Sun today.