Science topic

Uranus - Science topic

Uranus are the seventh planet in order from the sun. It is one of the five outer planets of the solar system. It has five known natural satellites.
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What would happen if Earth was tilted at 33 degrees and what if Earth was tilted like Uranus and has the world's axis shifted?
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The Earth's tilt is responsible for the change in seasons; a 33.5 degree tilt would result in greater temperature extremes during the seasons. Uranus' tilt is likely due to an ancient impact. If Earth was like Uranus, seasons would be extreme! The summer Sun would be up 24 hours a day, leading to a scorching climate, while the winter hemisphere would be in freezing darkness. The north and south magnetic poles, which affect things like navigation, drift and even switch places back and forth over time. Earth's other kind of pole is the axis around which the planet physically spins. This axis has also slightly shifted over time.
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I cannot find any paper that deals with this question. There seem to be three schools of thought none seeming based on anything more than speculation.
  • the energy received from the Sun is balanced by radiation emitted by the Earth abet at longer wavelengths
  • the Earth releases slightly less energy than received as a consequence of global climate change.
  • Earth is radiating more heat energy than it receives from the Sun as it cools, a very slow process from the hot Earth interior.
As mentioned in the question the gas and ice planet's energy balance is somewhat mysterious. For example, Neptune is farther from the sun than Uranus but is either the same temperature or slightly warmer.. As a result of processes not fully understood, Neptune emits more than twice the energy that it receives from the Sun does Jupiter (almost twice as much as received and Saturn 2.3 times the energy from sunlight is radiated into space. It is odd that Uranus while it does generate more heat than it receives, much less than the other three aforementioned planets, it also has another energy puzzle both its polar regions have the same temperature even though one of the two is in total darkness. It appears to me that in this age of climate change comparative planetology is a useful tool to understand our planet as well.
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CGY: Whether Earth is not an ideal black body or not will not change the fact that all the planets mentioned "emit" , "glow", "shine" more energy than they receive. ... They contradict the conservation of energy.
No, they do not contradict the conservation of energy. There are however several effects to take into account.
CGY: "there is a very small amount of energy that comes from radioactive decay inside planets, so small that for heat balance calculations it is usually ignored."
For the overall heat budget for most planets, that is true, the Solar input is significantly greater than other sources.
CGY: Gentlemen the above statement is at odds with a number of things.
The stored heat from formation depends on the volume, the rate of loss depends on the surface area so larger planets can retain heat for longer. For a small planet like Mercury or Mars, the residual formation heat has almost entirely been lost, for Earth and Venus there is still a small amount and for gas giants it is dominant. At the time of formation, the gas giants with much greater gravity also generated more heat from accreting other bodies, but at present they are also farther from the Sun, have a lower surface temperature and so lose heat more slowly (the Stephan-Boltzmann Law).
For a rocky planet with a molten interior, a significant amount is released as Alfred says by the phase change on solidification. Rocky planets also have a much higher proportion of heavy metals and therefore radiogenic heat. There are few radioactive isotopes of hydrogen and helium but phase changes in the gas will also play a part.
For smaller bodies like the Moons of Jupiter, you also have to take tidal heating into account.
When it comes to calculating the surface temperature however, the input from the Sun dominates the overall balance. You can calculate the temperature as if the planet were a black body but none are even close to that. You have to apply an emissivity factor which depends on wavelength. If the atmosphere allows optical wavelengths in from the Sun but is reflective to infrared then the surface temperature must be higher than you would expect for a black body in order to radiate the same total energy as it receives from the Sun, from stored formation heat and radiogenic sources. That adds some tens of degrees for Earth but has a huge impact on Venus.
  • If you both are incorrect then Earth, Jupiter, Saturn, Neptune and Uranus clash with the first law of thermodynamics, or conservation of energy.
No, there is no clash but the topic is complex and needs careful and detailed modelling.
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Why do Mercury, Venus, Earth, Mars, Jupiter, Saturn, and Neptune spin counterclockwise?
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Please accept my belated thanks for your answer to my Research Gate discussion thread question "Why do Venus and Uranus rotate on their axes [and] or spin in a clockwise direction?" Currently, I have just completed and returned galley proofs for my article on "Darwinian Ideas and Marxian Idealism in Austen, Twain, Yeats, Camus, and Ishiguro" in the Routledge Companion to Literature and Class and also for my Elsevier chapter on "Artificial Intelligence for Heavy Vehicle Technology: Subtextual AI/HVT Imagery, Cultural Ethos, and Legal/Ethical/Moral Standards in The Long, Long Trailer. Currently, I am compiling a list of galley proof corrections for my chapter on "Toward a Quantum Theory of Cognitive Affect from Poe to Robotic Helpers: Newton, Arousal, and Covalent Bonding, which is scheduled for publication in Artificial Intelligence and Computing Logic: Cognitive Technology for Business Analytics, forthcoming in 2022.
In case you may be interested, I would also like to let you know that, only hours ago, a second answer arrived at this Research Gate discussion thread, contributed by a new scientific researcher whose principal scientific research linguistic areas are in German and Russian, I believe, with English as a third area. It would be of interest to me if you might be in agreement with the perspective he has presented on this RG discussion thread as an expert in the field.
Thank you very much!
With my best regards,
Nancy Ann Watanabe, Ph.D.,
Literature, Film, and Science
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This started in another discussion where this was introduced as a side issue, and I provided the following answer. Others might prefer to discuss this. My previous answer was:
First, why is rotation usually prograde? In my ebook "Planetary Formation and Biogenesis" I outline a mechanism that involves essentially monarchic growth for the giants, and probably for other planets. The mechanism avoids the plethora of planetesimals because over 80 years nobody has a clue how they could form - I proposed that the initiation is chemical, and bodies have special zones that favour very rapid growth. In the absence of major collisions, what happens is the biggest body moves towards Keplerian velocity, which is faster than the gas stream. That leads to a greater pressure on the leading face, and as the gas is also falling starwards it applies a torque to the leading face that provides prograde spin. (What happens next also gives the body an increase in angular momentum, and hence lift.)
Uranus and Neptune are problems because they effectively state on their side and somewhat retrograde. Pluto's rotation is almost certainly affected by whatever formed its moon system - presumably a collision - and I assume something like that must have happened for the Ice Giants. The planets Mercury and Venus originated in zones where there would be more rocky bodies formed, and thy would be bombarded randomly so there would be little rotation. Mercury seems to have got itself into some sort of resonance with the sun. Venus has a retrograde rotation, and the most interesting explanation I have seen for that is that thermal tides in the atmosphere lead to that in planets inside the so-called habitable zone. What happens is the hottest part of the atmosphere is about 3 pm, and that leads to atmospheric currents that apply the retrograde torque. Venus is actually limited here because it has so much atmosphere and therefore so much thermal inertia. If it had a bit less it would rotate faster retrogradely - if that theory is correct.
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The problem with pebble accretion is it has to be gentle as there is no mechanical strength until the object gets big enough to be gravitationally stable. If you look at small asteroids, their gravity is negligible, but they have craters which implied an impact with enough energy to melt silicates. Impacts could have quite high energies, and even moderate ones would scatter pebbles, like the result of a collision on a snooker table. The evidence is that the initial maximum sizes of the dust is about 4 μm. How does this form strong pebbles? I have nothing against pebbles, but there has to be something stronger holding them together, and mhy answer to that comes from chemistry. Chemistry, after all, is the the science of the interactions of matter, but astronomers and physicists seem strangely reluctant to consider it, probably because what is required for this problem is relatively obscure.
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As Voyager headed into interstellar space in August 2012, having been launched by NASA on September 5, 1977, to explore and photograph Jupiter, Saturn, Uranus, and Neptune, discovering volcanic activity on one of its moons, Cornell's legendary Carl Sagan asked the U.S. government to photograph the solar system from the perspective of its outer rim. Scientists were taken by surprise to observe Earth swaddled in a thick ray of light emitted from the Sun, extending like a radius to the circumference. Is this discovery early signs of a pivotal moment in the Sun's development spanning billions of years, progressing from the main sequence toward the next phase in the life of the Solar System? --------------------------------------------
The Farthest -- Voyager in Space
Special | 1h 37m 13s
Launched in 1977, NASA’s epic Voyager missions revolutionized our understanding of Jupiter, Saturn, Uranus, Neptune and their spectacular moons and rings. In 2012, Voyager 1 left our solar system and ushered humanity into the interstellar age.
Aired: 08/23/17
Expires: 08/14/19
At the end of "The Farthest - Voyager in Space," Carl Sagan points to the photograph of Earth as viewed from Neptune and tells his lecture audience he is indicating "Earth in a sunbeam" and to indicate he knows they are unable to see the image, he adds, "We live on a blue dot." Photographs Moon Solar System Sun
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This short video, released in 2017, appears like a Neo-Genesis narrative in which Carl Sagan speaks as a voice located in the future as he looks back nostalgically to a time when humanity lived happily on a legendary planet named Earth.
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"Once upon a time, we soared into the solar system for a few years, then we hurried back. Why? What happened? What was Apollo really about?" - Carl Sagan.
I researched this question. Funding, politics and technological difficulties were the answers I found.
I am curious, are there any other reasons why the U.S. or any other nation or nations that are capable have not returned?
And will it not be easier for these countries to work together.
The Sagan Series - Gift of Apollo
Business Insider - Astronauts explain why nobody has visited the moon in more than 45 years — and the reasons are depressing 40 Years After Moon Landing: Why Is It So Hard to Go Back?
@Parviz Parvin - Why did NASA abandon the lunar exploration? Why has NASA never come back moon since 40 years ago?
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It's complicated. Some would argue that Apollo was never about scientific exploration and achieved its goal as soon as the Apollo 11 crew returned to Earth on 24 July 1969: that it was, in other words, a Cold War exercise in soft power. There's no doubt that it was primarily geopolitical in motivation. NASA itself had doubts about Apollo's continuation, for lunar exploration was risky, with every new mission offering many chances for catastrophic failure that would undo the prestige gains previous missions had achieved. I think it can be argued that 14 and 15 were flown to restore prestige lost through Apollo 13 and that 16 and 17 were flown to undermine prestige the Soviet Union gained through robotic rovers and sample returners. Some within NASA wanted to shift to Earth-orbital space stations; that is, to get back to the track the agency had plotted out for itself in 1959. As part of that, the Administrator at the time traded away two Apollos (18 and 19) in the hope of obtaining support for a Station/Shuttle Program. Then there was Nixon's desire to end the Democratic JFK/LBJ Apollo Program and put his stamp on the space program, and intercenter rivalries, mainly between Marshall in Huntsville, with its evolutionary Apollo Applications Program (which became Skylab), and Johnson in Houston, with its revolutionary Shuttle Program (which killed 14 astronauts in 135 flights). There's a lot more to it, of course, and this does not address (except indirectly) why we've never created an opportunity to resume lunar exploration using crews. I think that, after Apollo, it became abundantly clear that the whole Solar System needs exploration and that Minovitch's work on gravity assist made the whole Solar System economically accessible to robots. More here:
David SF Portree