Questions tagged [apparent-motion]
The apparent-motion tag has no usage guidance.
20
questions
5
votes
1
answer
320
views
How will a planet on asteroid belt see Jupiter?
Is there any tool that can help me visualize this? If not, just how big and how visible would Jupiter would be in night/day sky compared to moon/sun? And how often would it be visible?
- 255
1
vote
0
answers
51
views
Looking for data and models for events of Sun and Moon apparent motion in distant past?
For the current Julian Era (from 1, 1, 4713 BCE to modern day), I am looking for a raw data tables or a model that allows to predict the following events related to apparent motion of Sun and Moon:
...
9
votes
1
answer
3k
views
Moon moving near horizon much faster than at zenith, reason? error?
I read that the apparent motion of the moon is approximately its diameter every hour.
However, we just observed the moon appearing to rise through a stationary cloud in about 10 minutes, it definitely ...
- 201
1
vote
0
answers
78
views
How to call the fear of no gravity? [closed]
In opposite to barophobia I can't google out a fear of the case, when a man is taken out of the ship and he must go through the spaceship's docks and he can't get the direction of gravity - in the ...
- 119
0
votes
1
answer
135
views
If Earth's rotational speed is zero at the North Pole, why do stars still have apparent motion?
The apparent motion of stars (and other objects) results from Earth's spin on its axis, hence the rising and setting of some stars, and the circumpolar nature of others.
If the ground is not moving ...
- 657
4
votes
2
answers
874
views
Deriving the apparent angular speed of a star
The angular speed of stars in the sky is constant but the apparent angular speed is not, due to the star moving faster on the celestial equator and slower near the celestial pole. The apparent angular ...
- 115
21
votes
3
answers
6k
views
Are there any old/ancient star maps that we can compare to today’s and see drastic differences?
Stars move through the sky very slowly, which is not noticeable in a human lifespan. I’m aware of proper motion of Barnard's Star and things of the sort but I’d like to obtain a noticeable record of ...
- 551
2
votes
1
answer
335
views
Is our Solar System moving independently through our galaxy?
I would like know if our Solar System is moving independently through our galaxy or is stuck on the Orion Arm which is revolving around our galaxy? Is our solar system an onboard passenger of the ...
- 123
4
votes
1
answer
220
views
Questions on apparent motion of superior planets
Question
Why is it that superior planets seem to oscillate up and down of the ecliptic, from the view of an observer on Earth, with a period equal to the planet's orbital period?
Additionally, why do ...
1
vote
0
answers
74
views
Why is rotational motion absolute, is the universe spinning? [duplicate]
When considering any object, one can say its translational movement is relative, depending on the point of view or reference frame adopted. If it moves at 1/4c relative to some observer, one might say ...
user16500
5
votes
1
answer
513
views
Fastest recorded apparent motion of a comet or asteroid seen from Earth (degrees/day)?
If I've done my maths correctly in this answer comet 2I/Borisov (C/2019 Q4) was seen to move about 0.2 degrees in 7 hours, which is almost 0.7 degrees per day.
I'm assuming this is pretty rapid ...
- 30.7k
4
votes
0
answers
84
views
Did Eudoxus describe the eclipitic on his sun motion model?
In the description of Eudoxus’s model for the sun he says one the three circles which describe solar motion is “the circle which runs along the middle of the zodiac”. Does this refer to the ecliptic ...
- 41
1
vote
1
answer
245
views
What does "all stop" mean in reality?
In science fiction, when a starship captain commands "all stop," the audience simply assumes that, like a terrestrial naval ship anchored to the ocean floor, the ship literally comes to a complete ...
- 550
2
votes
1
answer
522
views
What percentage of the celestial sphere can the Moon cover?
I was solving a task that said (paraphrasing):
What percentage of the night sky can the Moon cover during the entire
year, when observed from all points on Earth (what percentage of the
night ...
- 1,681
1
vote
1
answer
70
views
What is the apparent rotation time for a planet relative to an other planet?
Just my curiosity. This is not my assignment etc.
Let planet A take m Earth days to complete one full round around the Sun, and planet B take n Earth days for one full round around the Sun. Assuming ...
