Questions tagged [lagrange-point]

Questions on any of the 5 locations where a small object can maintain a stable orbital configuration with respect to two co-orbiting larger bodies.

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Would an accumulation of dust in a planet's L1 Lagrange point plausibly obscure it from Earth?

I'm designing a hypothetical newly discovered planet in our solar system that has an ecosystem comparable to Earth's that supports intelligent life. The explanation given for the planet remaining ...
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Is there a Lagrange point between the earth and the moon?

Is there a Lagrange point between the earth and moon where a space station could sit forever without orbiting around either? Just curious, but it seems like a place like that would be perfect for ...
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Do any equivalent of Lagrange points exist between galaxies?

I'm wondering whether there is a similar effect between Galaxies as we have between a planet and it's star. I know there are tidal waves between galaxies and that gravity seems to always be attractive ...
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2 answers
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Do the Sun's rays get focused at or near the L1 Lagrangian point?

I have seen so many schematic pictures of eclipses (solar and lunar), and in all of them, the Sun's rays are focused at a specific point (left of the Earth in lunar eclipses and a slightly left of the ...
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Time in 0 gravity points

If being close to a supermassive body like a black hole makes time pass more slowly for us than for an observer from a point of view with a weaker gravitational field, if we get to be at a point in ...
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Why is the L1 point (Lagrange) almost 1 million miles from Earth? Shouldn't it be closer to us?

Try to follow my simple logic: The Sun is almost exactly 333,000 times as massive as Earth, and gravitational strength increases linearly with mass, so the Sun's gravity is about 333,000 times ours. ...
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Convert Earth-centered coordinates to rotating libration point (RLP) coordinates?

I'd like to plot the path of an object near L2 (like the Webb space telescope) in a rotating libration point coordinate system. That makes it is easy to distinguish halo orbits from more general ...
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When does DSCOVR see the Moon transit Earth?

In 2015, NASA published the first images of the Moon transiting the Earth as seen from DSCOVR. The text accompanying these images says such a transit would be captured on camera about twice a year. I ...
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Is possible to identify the Lagrange L2 point in the sky from the earth?

I'm reading now that the James Webb observatory will be at L2 point. Is possible in any way to look at this point from here in earth? I mean... given my LAT and LON here what is the best time to have ...
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Why don't we find planetoids at L4/L5?

We find small objects (asteroids and dust) in the stable Lagrange points (L4 and L5), but AFAIK no moons (by which I mean a mass that accreted into a body, as opposed to debris that has been captured ...
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How do Lagrange points L2 and L3 form?

Five Lagrange points form between any two bodies in the space (say Sun and Earth). According to my understanding, Lagrange points L1, L4 and L5 can form because gravitation pull can cancel out here as ...
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Lagrange points for bodies in elliptical orbits?

Lagrange points are points of relative stability near the orbit of another, more massive body. Most of the examples of such points regard orbits with relatively low eccentricity. However, after ...
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Could the Moon placed near the Sun-Earth L1 point remain in a heliocentric 1:1 resonant orbit with Earth? If Earth were at 1 AU, where's the Moon?

This answer to How much mass can be put in an L4 or L5 and it still maintain reasonable stability? has left me with the gedankenexperiment of the Earth in a circular orbit around the Sun, and the Moon ...
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Why is the L3 Lagrangian point not perfectly stable? And why is the Earth-Sun L3 point a bit less than one A.U.?

I suppose the answer might involve general relativity, but still.... The L4 and L5 points are considered, theoretically, long-term stable, but not L3, on the exact opposite side of the Sun... And it ...
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How do you calculate the the z component of the vector that describes the position of L1, L2, L3, L4 and L5 (lagrange points)

I'm using this resource (will download a .pdf) to calculate the positions of all the Lagrange points in a 2-body system, but it's only concerned with the x and y components of their position vectors (...
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2 votes
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How long does the "eclipse" last on a space station at the L1 point between a moon and a planet last when the moon blocks the sun in front?

The situation I am asking about is as depicted in the picture. Supposing I have a space station staying perpetually at the L1 point, the moon will completely block the space station from all sunlight ...
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IAU 2018 Exoplanet definition

In 2018 the IAU produced a definition of an exoplanet: The current official wokring definition of an exoplanet as amended by IAU Comission F2: Exoplanets and the Solar System in August 2018, reads as ...
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Fate of a planet orbiting a Lagrange point behind a star?

Let's say there is a planet orbiting at L5 behind a star, which is in turn orbiting a more massive star, like so: What is the ultimate fate of this planet? I'm predicting that it will spiral into the ...
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Why can't ESA/NASA build a handful of Gaia telescopes and launch them into different positions in space for better accuracy?

I've noticed that many stars in GAIA DR2 have highly uncertain distances. Why can't a space agency send multiple Gaia spacecraft into orbit around different places (One in L2 Earth, one in ...
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2 votes
1 answer
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Would an object placed at L1 be seen in front of the Sun from Earth?

Does anything placed at the Lagrangian point L1 between the Earth and Sun obscure the Sun like a transit of the innermore planets? The James Webb telescope is to be placed at L2, but if it was placed ...
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Could there be a planet at the barycenter between two or more stars revolving around each other?

In binary star systems, could there be a planet the stars revolve around, with eternal day on all sides? 1st scenario: Imagine a binary system consisting of two Sunlike G5V stars of 1 solar mass each, ...
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Why are telescopes positioned in Lagrange points?

In this Wikipedia article about the list of space telescopes to be launched (which I assume is exhaustive), of the 11 telescopes yet to be launched, 6 will be positioned at the Sun-Earth L2 Lagrange ...
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Determining the area of Lagrange Points

I have looked into Lagrange points a decent amount and I see many images that show the L4 and L5 locations as wide sweeping areas. Jupiter's Trojan asteroids are a good example of this. As well, L3 ...
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Are Sun-Earth L1 & L2 points generally considered outside the Earth's Hill Sphere?

This image from Wikipedia of the SE Lagrange points and the Hill Spheres suggests that the SEL points are outside the Earth's Hill Sphere. (The Hill spheres are the circular regions surrounding the ...
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Lagrange points and the radius of the Hill sphere

(Disclaimer: I know the "Hill sphere" is just an approximation of something which isn't genuinely spherical.) In a two-body system, the approximate formula for the Hill sphere radius of the smaller ...
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2 votes
1 answer
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L2 point ephemeris (celestial mechanics)

I'm a master student and I am trying to get the L2 ephemeris for some calculations in my master's project. It was kinda hard to find a file with the L2 ephemeris, but once I found it, I tried the next ...
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2 votes
2 answers
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Does the Lagrange L1 point have a 'size'?

Like in cubic kilometers, what is the size of L1 "area of influence"? being unstable I guess that size can vary?
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What fraction of the time is EM-L2 in darkness on average?

This answer to the question How wide is the Moon's umbra and penumbra at EM-L2? calculates the widths of the umbra and penumbra at a distance from the Moon equal to the distance from EM-L2 from ...
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How wide is the Moon's umbra and penumbra at EM-L2?

Measuring the total width of the Moon's umbra and penumbra at EM-L2, 64,700 km, how wide would the shadow be?
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How strong are the Lagrange Points of Earth?

How strongly are objects bound to the Lagrange points of Earth that they inhabit in them in the same way Jupiter's Trojan meteors are entrapped in its Lagrange points? In the co-moving frame with the ...
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6 votes
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How can Earth-Sun Lagrange points L1 & L2 even be semi stable considering the moon?

I know that the Earth-Sun Lagrange L1, L2, and L3 points are not considered stable over longer periods, especially when compared to L4 and L5... But, with the moon orbiting the Earth in the general ...
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Will the JWST be affected by dust at L2 (gegenschein?)

Gegenschein is a "faint brightening of the night sky" at the anti-solar point. A naked eye limiting magnitude of about 7.6 might enable an observer to make out gegenschein. The Wikipedia article on ...
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Will JWST be as durable as the hubble telescope?

JW Space Telescope is designed for a 5-10 year mission duration. Seeing as Hubble and other space missions have paved the way for JWST for reliability issues, It even has zero friction gyro's with 100+...
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3 votes
1 answer
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Does earth's Umbra reach Sun-Earth L2?

Moon can be fully eclipsed by the virtue of being fairly close to Earth. Any body distant enough will not be eclipsed fully, Earth's disc not fully covering Sun's disc. How's that for anything at the ...
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What would the apparent size of the four stars in the Capella system be from the L1 point between the first pair?

Capella is a system with four stars in two binary pairs (source: Wikipedia). If an observer were located at the L1 LaGrange point between the larger pair, how many degrees of the sky would each of the ...
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Theoretically, can a solar system evolve around lagrange points

My question is, during the evolution of a solar system is it possible to end up with a massive planet around a star with two small planets around their $L_4$ and $L_5$. Since we know it is not ...
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4 votes
1 answer
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How (un)stable are the Lagrangian points 1, 2 and 3?

A couple questions, please: I know that the Lagrangian points 1, 2 and 3 are unstable and special Lissajous orbits plus some station-keeping are required to place a spacecraft around them. But I was ...
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L4 and L5 stability

For what I know, L4 and L5 are high points. Although, they are stable points. Why? I thought it was the same being a high point and being a unstable point.
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What is a "jumping trojan"? And what do their orbits look like?

I was googling Neptune's trojan companions and found on Wiki this claim about ~200 km diameter (316179) 2010 EN65: " the object is actually a jumping trojan, is jumping from the Lagrangian point ...
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Asteroids in langrangian Points 4 & 5

There are Asteroids "trapped" in Jupiters Langrange points 4 and 5 called trojans and greeks. Are there any asteroids in the earths L4 and L5? Have we seen asteroids in Lagrange points of the earth ...
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Can we observe what objects exist at the L3 positiion of planets of our solar system?

From what I understand Earth's L3 is obscured by the Sun, so is that true for our viewpoint of the other planets? Or, are there times when other planets are on the other side of the Sun from Earth and ...
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L4&L5 positions?

I know that, in L4&L5, the distances to the two main bodies should be equal. Still, how can I calculate that distance with accuracy? How can I know that that distance is inside the equipotential ...
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Do Pluto and Charon have unusual Lagrange points?

The usual examples of Lagrange points one most commonly encounters, Sun-Earth and Earth-Moon Lagrange points, are examples of 3-body problems where $M_1\gg M_2\gg M_3$. The Pluto-Charon system, ...
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7 votes
2 answers
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Can the Gaia telescope detect small temporarily captured asteroids near its Lagrange orbit?

The Gaia space telescope is in a Lissajous orbit around the Sun-Earth Lagrange point 2. The orbit period is about 180 days and the size of the orbit is 263,000 x 707,000 x 370,000 km. It has been ...
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Is there a ceiling for stable L4 or L5 masses?

L4 and L5, the Lagrange points 60 degrees leading and trailing an orbiting body, are famous for being stable. A well known example is the Trojan asteroids at the Sun-Jupiter L4 and L5. Nodding to ...
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Maximum Amplitude of a Lissajous Orbiting Object in a L4 or L5 Position

I stumbled on The Lagrangian points during some wikipedia reading. After looking at the gravity contours, I naturally come to the conclusion that the L4 & L5 should have a wave pattern and then ...
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20 votes
1 answer
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How stable are Lissajous orbits?

Now that the Gaia Space Telescope is on it's way to the Sun-Earth L2 Lagrangian point (SEL2), I start wondering about the stability of Gaia's orbit there. The Planck Telescope is already there, as was ...
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21 votes
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Parking a telescope at a Lagrange point: is this a good idea from a debris point of view?

The James Webb space telescope is supposed to be located at the Earth-Sun L2 Lagrange point. Do we expect the region around that point to have a higher concentration of space debris, asteroids, dust,...
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