Questions tagged [earth]
Questions regarding the planet on which humans live; the third planet from the Sun.
110
questions
20
votes
2
answers
6k
views
Why is the Moon receding from the Earth due to tides? Is this typical for other moons?
After reading the Q&A Is the moon moving further away from Earth and closer to the Sun? Why? about the tides transferring energy to the Moon and pushing it from Earth, I have a question:
How is ...
- 1,586
16
votes
2
answers
4k
views
Will the Earth ever be tidally locked to the Moon?
From my basic understating,
Momentum is being transfered from the Earth's rotation to the Moon's orbit by tidal friction. The Earth's rotation slows down and the Moon receedes from the Earth as it ...
- 161
3
votes
3
answers
2k
views
Inverse of the sunrise equation - finding locations with a given sunrise time on a given day
I'm working on a project for fun where I represent some sleep data geographically. For a given day, I have a date, a time for falling asleep that night, and a time for waking up the next day. The idea ...
- 33
7
votes
1
answer
4k
views
Are there accurate equinox and solstice predictions for the distant past?
I am trying to find information on the equinox/solstice dates before 1600, more exactly referring up to 10,000 BCE so as to create a sort of calculator on an Excel spreadsheet.
I have read about the ...
25
votes
2
answers
3k
views
Is it a coincidence that both the Sun and the Moon look of same size from the Earth?
The Sun is huge, when compared to the Moon. Despite the huge difference in their size and distance from Earth, is it purely coincidental that they both look almost the same from Earth?
- 361
8
votes
1
answer
2k
views
Effect of the obliquity of the ecliptic / tilt of the Earth on the equation of time
In attempting to answer the question “why aren’t changes in sunset and sunrise times symmetrical around the solstices ?” I’ve got stuck on being able to explain the effect of the obliquity of the ...
- 83
39
votes
4
answers
5k
views
Why does the Moon appear gray when passing between the Sun and the Earth?
Shouldn't the Moon appear as bright as a full Moon seen at midnight from Earth?
The photo was taken by DSCOVR at Lagrange point 1.
In the picture, The Moon appears dark gray. Of course the Earth ...
- 501
26
votes
3
answers
1k
views
Are we made of the stuff of one star or more stars?
[T]his coincidence enabled stars in the late stages of their lives to turn helium into carbon, oxygen and most of the other atoms that you and I are made of. [...] [W]e're made of star stuff.
Max ...
- 361
24
votes
2
answers
5k
views
Can you see man-made lights on the dark side of the Earth from the surface of the moon with the naked eye?
This question is prompted from a comment on this answer:
Could a person on the surface of the moon see man-made lights on the dark side of the Earth with the naked eye? If not, how much magnification ...
- 343
13
votes
6
answers
26k
views
Why doesn't the sun pull the moon away from earth?
If the suns gravitational pull is strong enough to hold much larger masses in place (all the planets) and at much greater distances (all planets further away from the sun then earth) why does it not ...
- 351
11
votes
1
answer
4k
views
If Theia really crashed into Earth, did it impact Earth's axial tilt?
The great-impact theory is widely accepted for the formation of moon. If Theia (often described as a Mars-sized rock) really crashed into Earth, did that make an impact on Earth's axial tilt?
- 2,610
10
votes
3
answers
2k
views
What orbital period would produce one New Moon (and one Full Moon) each year? What other effects would this produce?
I am interested to know whether it's possible for the moon to orbit the earth at such a rate that we would see only one New Moon and one Full Moon a year. If so, what other effects would we experience?...
- 231
9
votes
5
answers
11k
views
What point does Earth actually orbit?
If we consider the two largest masses in our solar system - the Sun and Jupiter, by themselves, they will orbit a common barycenter which is somewhere offset from the Sun's center in the direction of ...
- 783
77
votes
4
answers
10k
views
How does the Earth move in the sky as seen from the Moon?
I just want to be sure I am visualizing this correctly, because it seems odd. The Moon is tidally locked to the Earth but there are wobbles to its motion due to libration. So from a point on the ...
- 1,569
18
votes
2
answers
4k
views
Why do stars appear to twinkle?
Sometimes at night you will look up to the stars and they will appear to twinkle, getting brighter and darker in bursts.
Why does this happen? Is this because of our atmosphere? Would they twinkle ...
user96
17
votes
6
answers
12k
views
Moon's orbit around the Sun
The Earth revolves around the Sun and the Moon revolves around the Earth.
Out of curiosity I started thinking about the orbit of the Moon around the Sun and expected (assumed) it to be as follows:
...
- 173
8
votes
2
answers
7k
views
Where exactly does the Moon flip, given that it appears the other way up in the other hemisphere?
I've read in multiple sources that the Moon appears the other way up in Northern Hemisphere vs Southern Hemisphere. Here is one that explains why: Does the Moon look different in the northern and ...
- 191
8
votes
2
answers
4k
views
2
votes
3
answers
2k
views
Calculate position of the Sun in ECEF
I'm making a very basic orbit simulator in C# using the Helix Toolkit.
I want to position the Helix lighting object at the sun, but also be able to calculate solar eclipse by the moon and earth for a ...
35
votes
3
answers
4k
views
Could any known, living organisms on Earth survive on Mars?
No life has been discovered outside of Earth (yet?), but do we know if anything that would be considered "living" on Earth could conquer Mars? (or maybe Venus?)
With the Mars One project on the way, ...
- 1,324
15
votes
2
answers
5k
views
How bright is the full Earth during the lunar midnight?
At lunar midnight (i.e. the new moon as seen from Earth), the Earth is in its full phase with its entire disk in sunlight, and it is the brightest object in the lunar sky. How bright is it, and how ...
- 2,123
14
votes
4
answers
3k
views
How did the Earth come to be in orbit around the sun?
I'm not sure if this post should be in the physics subject forum, but this seems to fit here too. I have been reading a book about chemistry and how the universe came to be with the theory of stars ...
bobthebuilder
13
votes
1
answer
448
views
Changes to Earth's orbit
Any time a spacecraft comes in close proximity to a planet and if the spacecraft has the right angle then it is able to use the planet's velocity to move itself further into space.
According to ...
- 231
13
votes
3
answers
16k
views
Life planets orbiting black-holes. Can/Do they really exist?
So, I watched Interstellar and if you watched it too you know that there's a planet orbiting a black-hole, they call it Miller's Planet. According to the movie, every hour on Miller's Planet is ...
- 241
12
votes
5
answers
6k
views
What mechanism causes oscillations of the solar system's orbit about the galactic plane?
In a recent paper (news release here) Lisa Randall and Matthew Reece propose that a dark matter disk coinciding with the galactic plane together with the solar system's oscillations through the ...
- 522
11
votes
7
answers
5k
views
Why are the time zones calculated as 360°/24 and not 361°/24 or 360°/23.933?
Background: I'm training to be a geography teacher. Currently I have practice lessons and I'll be discussing solar time and standard time with the class. Now I stumbled over an issue to which I could ...
- 139
10
votes
1
answer
15k
views
How would Earth's climate differ if it's axis were tilted around 90 degrees like Uranus? [closed]
As the title states, what would the effect on Earth's climate be if it's axis were tilted approximately 90 degrees like Uranus?
I'm specifically wondering about the effects on seasons, temperature, ...
- 527
10
votes
3
answers
1k
views
Can Earth host another natural satellite than the Moon?
Are there orbits with long-term stability (astronomical time scales) around Earth? Low altitude orbits will decay due to friction with Earth's atmosphere. Inside Earth's Roche limit, a Moon could not ...
- 783
10
votes
2
answers
2k
views
If the Sun got larger, but maintained its luminosity, would the Earth get hotter or colder?
A recent question If the Sun were bigger but colder, Earth would be hotter or colder? asked - if the Sun got bigger and cooler, would the Earth heat up or cool down. I think the answer to that is ...
- 146k
9
votes
3
answers
585
views
If 50 tons or more of debris falls to earth everyday, is Earth getting heavier?
In turn, would that increase our gravitational pull?
- 365
8
votes
1
answer
7k
views
What is the angle between the equator of the sun, and the plane of the Earth's orbit
I want to know the angle between the plane that passes through the centre of sun and is perpendicular to its spin axis, and the plane that contains the orbit of earth around sun?
Is this a fixed ...
8
votes
4
answers
3k
views
Did we ever actually see the earth revolving around the sun? Is the geocentric model completely disproved?
Did we ever actually see the Earth revolving around the Sun?
Also, is the geocentric model completely disproved or was it sidelined because the heliocentric model made things easier to understand?
(...
- 199
8
votes
1
answer
2k
views
How likely and severe is the threat of a gamma ray burst to earth?
In the National Geographic article: http://news.nationalgeographic.com/news/2009/04/090403-gamma-ray-extinction_2.html it is suggested that a gamma ray burst likely caused a mass extinction in earth's ...
- 4,355
7
votes
1
answer
859
views
Effects of the solar tide on planets
It’s well known that (lunar) tides on Earth result in a transfer of angular momentum from Earth proper to the Earth–Moon orbital motion. That’s why the Moon resides now in a high Earth orbit, and ...
- 270
7
votes
1
answer
180
views
Why do transits of Earth across the Sun seen from Mars follow a pattern of occurring after 26, 79 then 100 years?
According to this answer transits of Earth across the disk of the Sun as seen from Mars:
The (Arthur C.) Clarke story is quite correct. Earth (and Moon) would transit the sun from the viewpoint of ...
- 31.3k
5
votes
3
answers
1k
views
How much magnetic attraction is there between the Sun and Earth?
How much magnetism is there between the Earth and Sun? Would the distance from the Sun differ for not the Earth iron core and how much?
- 1
4
votes
1
answer
348
views
Stellarium simulation
I'm interested lately in Stellarium and the functionalities which it provides especially scripting. I want to make a simulation that shows the celestial sphere with some planets like Venus, Mars, and ...
- 141
3
votes
1
answer
657
views
Equations for coordinates of solar system objects
I would like to write a program that visualizes the solar system. To do this, I would need equations for calculating the coordinates of each solar system object at a given time. Where could I obtain ...
- 31
3
votes
2
answers
257
views
What is the future of our universe?
Is the universe heading towards a Big Freeze, a Big Rip, a Big Crunch or a Big Bounce? Or is it part of an infinitely recurring cyclic model?
- 131
3
votes
1
answer
839
views
What is the distance of Earth from the 7 planets, moons and the Sun at a point of time?
I wanted to know the distance of the 7 planets (Mercury, Mars, Venus, Jupiter, Saturn, Uranus, Neptune ) each (or at least 5 planets) from the earth and the angle that it will make with a line ...
- 97
3
votes
1
answer
2k
views
What makes the Earth rotate infinitely around its axis?
I was reading two sites before I posted the question here. One site says something like that the collisions in Universe eventually set the planets rotating, another site says that our planet is formed ...
- 133
3
votes
2
answers
3k
views
If the earth stopped rotating, would we really fly inertially at 1000mph? [closed]
I heard this on Prof. Neil Tyson's StarTalk podcast (this episode) and had a question about it. In a Q&A session, a listener had asked what would happen if Superman really did stop the earth from ...
- 147
3
votes
2
answers
438
views
As the Moon and the Earth are predicted to get into tidal lock, how slow would the Earth rotate?
This answer to Will the Earth ever be tidally locked to the Moon? supports the widely held thinking that during the Sun's red giant phase or later the Earth and the Moon should be tidally locked to ...
- 1,080
2
votes
2
answers
360
views
Why doesn't smashing larger and larger bodies incrementally into a rocky planet create a star?
Let's start with a stationary Earth. If we smash a few Mercury-sized objects into the Earth, the Earth begins to accrete mass. Repeat this step with larger and larger objects, until we start impacting ...
- 6,613
2
votes
2
answers
146
views
What measures are currently in place to detect asteroids on possible collision courses with earth?
I know some measures must exist, but I have no idea what the programs are, what organizations are involved, or how effective they are.
- 874
2
votes
3
answers
2k
views
Sudden Effects of Sun Disappearing [duplicate]
It takes 8 minutes for the sun's light to reach earth. If the sun were to instantly disappear, what would happen? I imagine that Earth would fly away on a path tangential to its orbit. What would ...
- 39
1
vote
1
answer
383
views
Calculating the orientation of the night sky
How would one calculate the rotation/tilt of the earth to simulate the Night Sky in a self-written tool or app. I am trying to built an app for my telescope to show me on my phone what I am looking at....
1
vote
1
answer
349
views
What is the exact time of sun stay in each zodiac every year on sidereal year duration?
I tried to reverse engineer from astro-chart times at which sun stays in a zodiac.
Here is the list.
...
- 123
139
votes
3
answers
23k
views
How loud would the Sun be?
Sound can't travel through outer space. But if it could, how loud would the Sun be? Would the sound be dangerous to life on Earth, or would we barely hear it from this distance?
- 1,159
48
votes
3
answers
15k
views
If Earth is tilted, why is Polaris always above the same spot?
Why is Polaris, the North Star, always above (or near) the North Pole? If Earth is tilted, Polaris' path should be in winter 23 degrees away from its path in summer, or not?
- 379