It is known that the Earth's orbit around the sun changes shape every 100,000 years. The orbit becomes either more round or more elliptical at these intervals. The shape of the orbit is known as its "eccentricity." A related aspect is the 41,000-year cycle in the tilt of theEarth's axis.
It is during that full moon and the new moon.
The “S” phase which is the phase of DNA synthesis
From tiny blood cells/vessels!
Hope this helps!
Let us look at the what, why and how of studying extreme places like the deep earth and the deep space. Scientists need to figure out as to 'what' they want to look at such places, be it a new exotic creature or bio-genesis (birth of life). Unless there are several testable hypothesis constructed, such a study cannot begin. The 'why' aspect deals with the purpose of such research and expeditions. Is it of any use to the humans, or will it improve our current understanding of a phenomenon? The 'how' aspect deals with the technology and the economic assistance that can help in undertaking such a research. All these are the challenges that needed to be thoroughly considered to make such a research or expedition possible.