Questions tagged [earth]
Questions regarding the planet on which humans live; the third planet from the Sun.
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Does polar motion cause the Earth ellipsoid to change?
The Earth is oblate because it spins and is not a rigid body. Since its spin axis changes relative to its crust, then the meridian of maximum diameter changes too, right?
I understand that polar ...
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A couple of questions about Earth's hypothetical planetary rings
From what little I know of this subject, It should be possible for Earth (Or a planet the size of Earth) to keep a system of Planetary Rings. However, looking around the internet only gives me info ...
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Simulate earth, moon, sun constellation with dates
I would like to simulate the three object distance, specifically the distance of the moon to both, sun and earth for further investigation into tide prediction.
What would be a good starting point ...
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Could we make ourselves detectable for aliens with JWST-like technology?
The James Webb Space Telescope is going to take spectra from planets during transit in front of their central star. By that, spectral changes can identify if the planet possesses an atmosphere and ...
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Do differentials in the Earth's density cause the flyby anomaly?
The flyby anomaly is an occasional, unpredictable, and as yet unexplained discrepancy in acceleration of satellites when they pass close by the Earth. It causes an increase of up to 13 mm/s during ...
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To what extent does the increased average airmass the Sun's light passes through contribute to the seasons?
The traditional explanation for the cause of seasons I have heard is that because of the angle of the axis of the Earth with respect to the ecliptic, the angle at which light rays hit the Earth's ...
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How does NASA estimate the size of the population of Near-Earth Objects (NEO) of diameter>140 meters?
In 2018, the US Congress passed a bill to allocate budgets and mission goals to NASA.
Section 321 of that Bill mentions a goal for detection of NEOs of diameter >140 Km. Quote:
(1) The George E. ...
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Other side of Earth when the Dinosaur-killer struck
When the (Chicxulub) asteroid hit Yucatan, what was it like in the minutes, days and weeks afterward on distant locations on Earth?
Related
How loud was the asteroid that killed the dinosaurs?
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What's the first written record of the moon being tidally locked to the earth?
I couldn't find references as to who first noticed (wrote down) that the moon was tidally locked to the Earth. This, to me, doesn't seem obvious from first glance, and looks like something only found ...
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Earth-Centered Earth-Fixed coordinates with respect to heliocentric coordinate system at vernal equinox
I am trying to calculate the position of a point on the Earth's surface with respect to the Sun's center at a certain date and time.
For what I am trying to do it is OK to ignore precession of Earth's ...
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Calendar times of equinoxes
I know that the dates and times of equinoxes are not the same every year, due to precession of the axis and perhaps other effects such as the year not containing an exact number of days. The ...
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If the distance from Earth to the Sun was filled with air, how loud would the sun be?
Based on this question: If there was air between the Sun and Earth, how warm would we get?
Many sources state that if sound wasn't limited by matter, we would hear the Sun at around 100dB constantly, ...
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The electron–cyclotron maser emissions from Earth
The first-ever detection of radio signals caused by the electron–cyclotron maser mechanism outside of the Solar System, on Tau Bootis b was recently published (here). This phenomenon causes huge radio ...
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Has the computed change of the axial tilt ever been measured?
Earth, the 3rd planet from the Sun, sometimes faces earthquakes and seaquakes that are so strong that they reportedly change the axial tilt and/or the rotation velocity. These changes are merely ...
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Keplerian Elements for the Moon and Earth around their Barycenter
So I'm looking to replicate the inner Solar System to a decent degree of accuracy. So far I've been utilizing the Keplerian Elements and Equations for the planets, as shown here. There is one issue ...
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Orbital decay of the Earth's orbit and Earth's moving closer to the Sun
If we consider orbital decay of the Earth's orbit, then can we counter argue with the following reasons?
Due to tidal effects transferring small amounts of angular momentum from the Sun's spin to ...
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Calculating Angle Between Two Planets In Heliocentric Orbit
My goal is to calculate the retrograde of Mercury. What I've been working from is the book, Practical Astronomy With Your Calculator 3rd edition. I've made some progress, but I seem to be stuck with ...
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What is the period of the 'cycle' of Earth's ecliptic variation, relative to the 'invariable plane'? 70,000 or 100,000 years?
The plane of Earth's path around the Sun, the ecliptic, is different from the average of the solar system's as a whole (the invariable plane) by about 1.57°....
Our path around the Sun, though, goes ...
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How is bond albedo calculated?
According to this website, Bond albedos are computed by calculating the ratio of the flux reflected by a planet (integrated over wavelength) to the total stellar flux incident on the planet.
Three ...
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Meteor size and frequency distribution for Earth vs. moon or other planets?
I struggle to find an answer to the at-first-sight simple question if or how the size distribution and frequency distribution of incoming rocks hitting the ground or the atmosphere vary from Earth, to ...
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Where and when will someone on Earth be standing with the floor parallel to the Ecliptic plane?
I have been trying to figure this out and I think the answer might be - once per day for anyone living on the Tropic of Cancer or Capricorn. Is that right? To be clear - I want to know where on Earth ...
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Orbitally convenient Mars-to-Earth transit times?
Are there any peculiar solar system layouts that would result in highly efficient transits between Mars-to-Earth? I am aware of a Hohmann transfer orbit, but can other planets be used to "sling-shot" ...
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Angle of the Sun during winter solstice
What is the angle of the Sun on the eastern horizon at 35° latitude if it is the winter solstice?
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Angle between earth's angular momentum and earth's axis
I think this picture is correct because for earth astronomical day is slightly shorter than solar day. (Is it a rule of thumb for planets? Where can I read such data?)
Source
So the angle between ...
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Just out of curiosity. What's this curvature per unit length for a sphere? I see a lot of flat earthers using it.
I've seen most flat earthers mention if earth was a sphere the earth should curve at x value per unit length. Is that even a proper logic? Radius of curvature is constant for sphere and a circle of a ...
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Convert from magnetic coordinates to true coordinates
I am working with the IGRF (International Geomagnetic Reference Field) model and from a journal article found here, I am able to compute the earth's magnetic field at any point in spherical ...
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What is the formula to input date, time and longitude. Where I can get latitude of the civil twilight back?
I am making a watch app, where I need to know where there is currently sun, and where it's not.
I need to have some sort of formula/function to insert: date, time and longitude, and get back the ...
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What is the highest albedo of the earth's surface facing the sun ever measured?
This website (page 26) claims that full-earth-shine on the moon is 100 times greater than full-moon-shine on earth. The figure 100 is made up of the difference between the size of the earth and the ...
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How do I calculate the elevation angle to the horizon?
I'm creating an app to visualize the southern area of the moon from a first-person perspective. I'm trying to determine if a point on the surface is a "checkpoint," where the elevation angle ...
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Maximum and minimum masses and sizes of giant planets?
What are the minimum & maximum masses and diameters of giant planets?
Minimum end of the scale
Earth has mass of 1 Earth mass and a mean radius of 6,371.0 kilometers, and thus a mean diameter of ...
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