Trending questions
15,732 questions
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3i/Atlas Alignment of its rotation axis with the sunward direction at large distances
https://avi-loeb.medium.com/a-14th-anomaly-of-3i-atlas-alignment-of-its-rotation-axis-with-the-sunward-direction-at-large-e8a08a0705d4
Please read the above article. It confused me since December. ...
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A fictional habitable moon of a gas giant, where the moon has a 24-hour day like Earth [closed]
I saw an argument on a forum about a fictional moon orbiting a gas giant, with a 24-hour day. Which of these arguments is correct?
Or maybe they're all wrong, and this would need something else?
Guy A:...
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How is numerical precision/accuracy determined when converting RA/Dec in sexagesimal format to decimal degrees for angular separation calculations?
Problem
I'm trying to complete an assignment for my astronomy course, but I'm having trouble understanding how accuracy is determined when converting equatorial coordinates in sexagesimal format to ...
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How can 3i/Atlas flip 180 degrees at Perihelion?
short recap: Before and after Periheion 3i/Atlas rotation axis aligns to the sun. See above. What happened right at Perihelion (closest to sun) when earth blocked the view? Did 3i/atlas flip 180 ...
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How can one quickly screen a disk galaxy dataset for large-scale asymmetry?
I am looking for practical ways to quickly assess whether a disk galaxy dataset
shows large-scale asymmetry (e.g. possible stress-driven or lopsided structure)
before doing any detailed modeling.
...
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How close could a star get to our solar system without disrupting the planets' orbits?
Is there an easy way to calculate how close a star of given mass could get to our solar system without disrupting the orbits of the planets? Just looking for a rough estimate, nothing too involved
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Clarifying a Fundamental Issue in Luni-Solar Theory: Sidereal vs Tropical Lunar Motion [closed]
I would like to ask a precise and well-defined question about the foundations of classical luni-solar theory, motivated by direct observation and long-term numerical simulation (e.g. Stellarium).
The ...
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Can someone please clarify why the angle KPX is (90+alpha)?
Question:
In the standard geometric construction of ecliptic coordinates on the celestial sphere, let
K be the north ecliptic pole,
P the north celestial pole,
X is the position of an object on the ...
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comet 3i/Atlas Larson-Sekanina Rotational Gradient Filter
I want to know if the 3 equidistant jets of 120 degrees seen in the 3i/Atlas comet is artifact of the Larson-Sekanina Rotational Gradient Filter. The following is the Larson-Sekanina output and the ...
- 153
2
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Hubble portal search name for comets
When I entered "C/2014 Q2" in the NASA MAST archive search box (see below). It can't find the Lovejoy comet. What is the right word to enter? Please give any other comet examples as other ...
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Why does Mars return to conjunction with fixed stars alternating sequences of regular intervals punctuated by much shorter intervals?
79-Year Repeating Cycle in Mars-Deneb Algedi Conjunctions: An Undocumented Pattern?
Background
I've been analyzing the conjunctions between Mars and the star Deneb Algedi (δ Capricorni, RA = 21h 47m ...
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Would a planet's obliquity be stable if it is tidally locked to its moon?
This scenario should become typical as the universe ages--a moon tidally accelerates and migrates until its parent planet's rotation equals the moon's, (mostly) preventing further drift.
But what ...
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What is the difference between two types of active galaxy?
What is the difference between blazars and quasars? Is the classifcation related to the black holes at their centres? What are the relative numbers of each type and do all the known examples have ...
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How do I definitively determine if the anti-tail of 3I/ATLAS is a perspective effect?
A tantalizing aspect of 3I/Atlas (or C/2025 N1) is its ''anti-tail'' seen in post-perihelion images, with some arguing it isn't a perspective effect.
Whereas an anti-tail had been seen for solar ...
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How do I select the correct frame for computing stellar aberration?
I'm trying to understand how stellar aberration correction is computed and am finding seemingly contradictory explanations across different software packages and references.
SPICE:
The documentation ...
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