Questions tagged [obliquity]

Questions about the angle between the rotational axis and the orbital axis of a celestial body. Obliquity is also known as axial tilt.

Filter by
Sorted by
Tagged with
6 votes
1 answer
102 views

Earth's Collision [duplicate]

It is my understanding that the Earth is tilted because it was struck by another object about the size of Mars. According to Newton's first law, the Earth should have continued to rotate along its ...
3 votes
1 answer
140 views

Could a super-Jupiter exoplanet in the habitable zone have an axial tilt?

I’m wondering if a massive planet (maybe 10 times the mass of Jupiter) in the habitable zone of a G type star could have an axial tilt similar to earth or if gravitational forces would erode the tilt ...
  • 779
-1 votes
1 answer
115 views

Which one of the gas and ice giants has the least varying orbital characteristics? [closed]

Which one of the gas and ice giants of our solar system has the least varying orbital characteristics (obliquity, eccentricity etc.)?
0 votes
1 answer
205 views

How to calculate the Sun's declination for a specific location based on the axial tilt of Earth throughout the year?

How to calculate the Sun's declination for a specific location (i.e. relative to a specific coordinate) based on the axial tilt of Earth throughout the year? Any algorithm for code available in this ...
2 votes
1 answer
397 views

How to calculate the Earth's axial tilt (obliquity)

How can I calculate the Earth's axial tilt in degrees. I tried Skyfield, Poliastro and PyEphem. I know it's changing -0.47"/year, and it was ...
  • 155
1 vote
1 answer
160 views

What is the difference between inclination and obliquity?

I'm trying to understand the differences between obliquity and inclination when it comes to a system of a planet orbiting a star. From what I understand, obliquity is the angle between the orbital ...
5 votes
1 answer
335 views

Does the axial tilt of Mercury and Venus vary?

The axial tilt of Mars varies greatly over time, with a tilt varying between 15 and 25° over the last million years, and varying even more over the last 5 million years. The Earth's tilt on the other ...
3 votes
1 answer
161 views

Is there any thing special with an axial tilt of roughly 25°?

Half of the planets in the solar system have an axial tilt of $25.5\pm 3^\circ$: earth (23.5°), mars (25.3°), saturn (26.7°) and neptune (28.3°). If random collisions in the early solar system caused ...
1 vote
1 answer
213 views

Why don't we see evidence of glaciation on Mars, similar to Earth's Ice Ages?

With all recent NASA activity surrounding Mars manned missions, it is surprising that given Mars orbital distance from Sun that there is not evidence of massive glaciation similar to Earth's Ice Ages. ...
8 votes
1 answer
1k 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 ...
8 votes
1 answer
215 views

What is the cause of the variation from high and low mean obliquity periods of Mars?

It is reasonably well known that Mars has a greater obliquity range than Earth, due to Mars lacking a stabilising influence of a large moon. However, the Martian obliquity seems to have gone through ...
user avatar
4 votes
1 answer
327 views

Is axial tilt direction correlated with semi-major axis direction?

Earth comes closest to the Sun every year around January 3. Winter solstice is at 21-22 December, merely some 12-13 days away. That means projection of Earth rotation axis onto the plane of its ...
  • 6,137
6 votes
2 answers
186 views

How does 67P rotate?

What can be said about 67P/Churyumov-Gerasimenko axial tilt? Is it fixed (if so, at what value), only changing with precession (at what rate?) or does 67P "tumble" with axial tilt changing over time? ...
  • 6,137
27 votes
3 answers
2k views

What is the accepted theory as to why Uranus' axis is tilted so severely?

The planet Uranus is another solar system anomaly, where according to the NASA profile has an axial tilt of 97.8 degrees, also considered to be retrograde. This NASA summary "Uranus" suggests the ...
user avatar