Coincidence or another hidden agenda?
Why do we never see the back of the moon?
The Moon is the closest planet to Earth and the brightest and most easily observable object in the Earth's night sky. Interestingly, because the Moon always faces the same way toward the Earth, for us humans living on Earth, we can always observe only one fixed side of the Moon.
We usually refer to the side of the Moon facing the Earth as the front side of the Moon and the other side as the back side of the Moon, and by this definition, we on Earth can never see the back side of the Moon. So the question arises, why does this phenomenon occur? Is it a coincidence or is it something else?
There are indeed many coincidences in the universe, not to mention that the emergence of our species is the superposition of a large number of coincidences. However, the phenomenon of "the moon always facing the same side towards the earth" cannot be considered a coincidence, but rather a "hidden agenda", but the so-called "hidden agenda" is not as mysterious as one might think. So mysterious, this is a phenomenon known as "tidal lock", we will understand the following specific.
First of all, we need to understand why many planets in the universe are similar to the shape of a sphere, simply put, this is the role of the planet's gravity because gravity can be infinitely superimposed, so when the mass of a celestial body reaches a certain level, its gravity will be strong enough to make the planet's material in the overall performance of a fluid-like state.
Ideally, when the matter of the planet reaches hydrostatic equilibrium, the planet would have a perfectly spherical shape, but in reality, this does not happen because various factors in the universe affect the shape of the planet, and the Moon is certainly no exception.
During its revolution around the Earth, the Moon is affected by the Earth's gravity, on the other hand, due to its inertia, the Moon also tends to move away from the center of mass of the Earth-Moon system, which we can call the "centrifugal force" in the opposite direction of the Earth's gravity, i.e., when the Earth's gravity In other words, when the Earth's gravity and the "centrifugal force" are in balance, the Moon can steadily revolve around the Earth.
(Note that the "centrifugal force" is a virtual force introduced for the sake of discussion, but it is a manifestation of the inertia of the object, so please pay attention to the distinction)
Depending on the distance from the Earth, the Earth's gravitational force and the "centrifugal force" on different parts of the Moon will be different, specifically the closer to the Earth, the greater the Earth's gravitational force, and the smaller the "centrifugal force", and vice versa.
Since the Moon is large enough, there is a significant difference between the Earth's gravitational force and the "centrifugal force" on the parts of the Moon that are farther apart, while the closest parts of the Moon are subject to the greatest Earth's gravitational force and the farthest parts of the Moon are subject to the greatest "centrifugal force". The closest part of the Moon is subject to the greatest gravitational force, while the farthest part is subject to the greatest "centrifugal force.
This affects the hydrostatic equilibrium of the Moon and results in a slight bulge on both the "side facing the Earth" and the "side facing the Earth", a phenomenon also known as "tidal bulge". This phenomenon is also called "tidal bulge", which can be simply understood as the shape of the Moon being pulled into an ellipsoid.
In the above diagram, A represents the Earth and B represents the Moon, when the Moon is in position 1, it is pulled into an ellipsoid (note: the actual situation is not so exaggerated). position.
Since the "tidal bulge" takes some time to recover, there will be a pair of parallel forces of equal magnitude and opposite direction, but not in a straight line, at the two ends of the "tidal bulge" formed by the Moon at position 1, one of which is the gravitational force of the Earth, and the other is the "centrifugal force". One of them is the gravitational force of the Earth, and the other is the "centrifugal force", which can be considered a pair of force couples.
We all know that the force couple can make the object rotate, so the moon will tend to rotate in the opposite direction of its rotation, which will reduce the original rotation speed of the moon. Conversely, if the rotation speed of the Moon is slower than the rotation speed, then when the Moon rotates to position 2, the rotation speed of the Moon will increase.
As we can see, with the above mechanism, the Moon's rotation and revolution will eventually be synchronized if the time is long enough, that is, for every revolution of the Moon around the Earth, it will complete its rotation exactly once, and this phenomenon is called "tidal locking".
According to scientists' estimation, the Moon was born about 4.5 billion years ago, so we can imagine that even if its rotation and revolution were not synchronized at the beginning of the Moon's life, the Moon should have been "tidally locked" by the Earth after such a long time, and this is indeed the case in reality.
As shown above, the moon we see now is actually rotating, but because its rotation period and rotation period are just equal, so the moon will always be on the same side toward the earth, and we on earth of course always can not see the back of the moon. This phenomenon is not a coincidence, but an inevitable result of the laws of the universe.
In fact, "tidal lock" is not rare in the universe, even in the solar system, for example, Mars, Jupiter, Saturn, Uranus, and Neptune's moons generally have a "tidal lock" phenomenon, and the most outrageous is Pluto and its The most outrageous is Pluto and its largest moon, Cajun, because they are both tidally locked to each other.
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Robert Jack
One of the secrets of emotional stability for adults is to keep the expectations of others to a minimum.
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As the war in Ukraine grinds on with no clear end in sight, the debate over what comes after the fighting has taken a sharper turn. The United States has signalled reluctance about committing troops to Ukraine once the war ends, even as the United Kingdom and France openly pledge to consider deploying forces in a postwar security role. The divergence has exposed differing strategic priorities among Western allies and raised new questions about how Ukraine’s future security will be guaranteed. While all three nations remain united in their support for Kyiv during the war, the emerging split over postwar troop commitments highlights the complexity of planning for peace in a conflict that continues to reshape Europe’s security landscape. What the UK and France Are Proposing British and French leaders have increasingly spoken about the need for long-term security arrangements for Ukraine once active hostilities end. 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European powers, facing the immediate proximity of the conflict, may feel a stronger need for visible reassurance measures, while the US assesses risks from a more global perspective. Implications for NATO Unity Although Ukraine is not a NATO member, the discussion has clear implications for the alliance. Any deployment of UK or French troops would be closely scrutinised for what it means for NATO’s role and credibility. NATO operates on consensus, and the absence of US support for a postwar troop presence could complicate coordination. Even if London and Paris act independently or as part of a smaller coalition, questions would remain about command structures, rules of engagement, and the political backing required for such a mission. At the same time, the situation underscores a broader shift within NATO, with European members increasingly expected to shoulder more responsibility. 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Copenhagen also hopes to use the opportunity to reinforce cooperative approaches to Arctic security, particularly in light of growing Russian and Chinese interest in the region. For Denmark, maintaining strong relations with the United States — while safeguarding Greenland’s autonomy — is a balancing act that requires careful diplomacy. Greenland’s Perspective Greenlanders themselves are increasingly vocal in the debate over their future. Many support greater economic independence and political autonomy, and local leaders insist that Greenlanders should have the final say over any decisions affecting their land and resources. The U.S. delegation’s visit highlights the need to consult Greenlandic authorities directly, rather than negotiating solely with Denmark. This approach is seen as a step toward more inclusive, respectful diplomacy, which acknowledges Greenland’s status as more than just a strategic asset. The Role of NATO and Transatlantic Relations Trump’s proposals regarding Greenland strained transatlantic relations, raising concerns among NATO members about the reliability of U.S. commitments. The arrival of bipartisan lawmakers in Copenhagen aims to reaffirm NATO solidarity and demonstrate that U.S. policy is consistent with alliance obligations. By engaging Denmark directly, Congress seeks to prevent miscommunication and maintain stability in a region that is increasingly vital for global security. Analysts note that Greenland’s location provides the United States with a critical vantage point for Arctic monitoring and missile defense, making cooperative relations essential. Global Implications The Greenland issue has broader consequences for international geopolitics and Arctic governance. Key points include: Resource security: Greenland’s rare earth minerals are essential for electronics, renewable energy, and defense technologies, making control and access highly strategic. Climate change and navigation: Melting ice is opening new shipping lanes, which could shift global trade patterns and increase competition for influence. Power dynamics in the Arctic: Russia and China have also shown growing interest in the Arctic, prompting the United States and Europe to strengthen alliances and prevent unilateral exploitation. The lawmakers’ visit signals to the international community that the U.S. is committed to diplomatic solutions rather than transactional or coercive strategies. Challenges Ahead Despite the visit’s diplomatic intent, challenges remain: Political polarization in the U.S.: Future administrations may have different approaches to Greenland, raising uncertainty about long-term commitments. Geopolitical competition: Russia and China continue to advance their presence in the Arctic, complicating cooperative efforts. Local autonomy: Greenlandic voices must be prioritized, or any policy may face resistance at the local level. Successfully navigating these challenges will require transparent dialogue, careful planning, and sustained international cooperation. The Path Forward The visit of U.S. lawmakers to Copenhagen is a cautionary and corrective measure. It signals that while Greenland is strategically important, it is not a bargaining chip. Future cooperation will likely focus on: Strengthening Arctic security frameworks Promoting economic development for Greenlanders Maintaining stability in U.S.-European relations Ensuring that Greenlandic voices remain central to decision-making This proactive approach reflects a broader understanding that diplomacy, not unilateral action, is essential in regions of high strategic value. Final Thoughts Greenland has moved from the margins of global attention to the forefront of geopolitical strategy and climate concern. The arrival of U.S. lawmakers in Copenhagen underscores the importance of measured, inclusive diplomacy in the Arctic, contrasting sharply with the impulsive rhetoric that characterized Trump’s Greenland proposals. As nations navigate the Arctic’s emerging opportunities and challenges, Greenland’s sovereignty and the voices of its people will remain central to regional stability, global security, and international cooperation. The lawmakers’ visit represents a step toward rebuilding trust, reinforcing alliances, and charting a sustainable path forward for one of the planet’s most strategically vital territories.
By Muhammad Hassanabout 4 hours ago in Earth
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