Is lagrange point L1 stable?

Is Lagrange point L1 stable? If I were to place a space station in L1 will it remain in orbit without any difficulty? If there are any difficulties, please mention them here along with any suggestions to overcome the difficulties, if possible....Read more

lagrangian points - Is this what station keeping maneuvers look like, or just glitches in data? (SOHO via Horizons)

I've been enjoying the JPL Horizons web interface and after I discovered the incredibly extensive database associated with SOHO (Solar and Heliospheric Observatory, also see for this answer I decided to learn more about the satellite's orbit.I exported a dataset of historical (and projected) orbit data for SOHO Spacecraft in 1 day steps using the following setup: I also exported the positions of the Sun, and of the Earth-Moon Barycenter the same way.Using the reduced mass of the Sun vs Earth-Moon Barycenter (EMB) system...Read more

lagrangian points - Why does DSCOVR's camera EPIC see at least 13 sunrises and sunsets per day?

In this NASA Goddard YouTube video titled "One Year on Earth – Seen From 1 Million Miles", I've gotten stuck on the line In this view, EPIC sees the Sun rise in the west, and the Sun set in the east, at least 13 times a day.edit: Listening carefully, it's "...see the sunrise... and the sunset..." and not "...see the Sun rise... and the Sun set...", so my transcription is not correct. I'll leave it, along with this note, because the distinction is important. I only caught it after reading the nice, concise answer by @Leorex through carefully.D...Read more

observation - Why are so many space telescopes placed in LEO instead of at Lagrange Points? And why do we hear about Hubble more than any Langrange-orbit telescope?

Here is the list of every space telescope launched by different space agencies - List of space telescopes. Most of the listed telescopes are placed in Lower Earth Orbit (about 95% of them). It's probably not an ideal location to place a telescope because of many obvious reasons like our earth radiates a huge amount of infrared radiation; as said by professor Michael Merrifield-"Its like doing astronomy with all the lights switched on" .Now here is the list of all objects placed at Lagrange points - List of objects at Lagrangian points. There ar...Read more

lagrangian points - Is it obvious or easily-proven that L4 and L5 must be in the parental orbital plane?

Looking at the question and answer and diagrams from Are Lagrangian points associated only with the smaller body? got me wondering.L4 and L5 each form an equilateral triangle with the two main bodies, with L4 ahead in the orbit and L5 behind it.But there's a whole circle of points equilaterally distant from the two main bodies, perpendicular to the orbital plane! Couldn't that be an orbit?On some intuitive level I feel like that's just obviously dumb, but for something so obvious, I sure can't put my finger on it....Read more

Do we have the capability to place a satellite in the Sun-Earth L4/L5 Lagrange points?

I was looking at the Wikipedia page on Lagrangian points, and I noticed that in the list of current and proposed missions, the only mention of the $L_4$ and $L_5$ points is a "this would be a good idea" proposal from the '70s. Presuming that Wikipedia's list is actually comprehensive (which it may easily not be), is the lack of proposed missions due to our inability to get a satellite there? Or is it just that no one has yet come up with a good reason to send one out there? Or do we just not have a way to get anything to stop there, so we cou...Read more

How Many Martian Lagrange points are there? ...And are they useful for satellites?

I know that the Sun-Earth system has 5 Lagrange points, and there are five more Earth-Moon associated Lagrange points; so ten in all that are in some way associated with the Earth.Since Mars has two natural satellites compared to Earth's one, would it have a total of fifteen associated Lagrange points? Might the points associated with Mars' natural satellites be in any way useful in terms of artificial satellite orbits?...Read more

L2 point in multi-moon system

For an SF novel, if there were two large moons orbiting a planet, let's say one moon the size of Earth's moon and the 2nd moon about 20% larger, and the planet roughly the size of the Earth, would the L2 point at the larger moon still exist and be relatively stable as it is in the Earth-Moon system (at least in the short term, e.g. for a matter of days)? You can posit the moons as orbiting opposite to each other around the planet, or you can posit them in resonance, I don't care as long as they are not too close to each other....Read more

Gravity cancellation point

Here is a question from ANTHE: an exam in India. The question is:Two point masses M and 3M are placed at a L distance apart. Another point mass m is between on the line joining them so that the net gravitational force acting on it due to masses M and 3M is zero. The magnitude of gravitational force acting on m due to M will be? (Please answer in terms of variables!)This question looked for me as the same lagrange point between sun and earth.Hope I will get the answer soon, thank you in advance....Read more

space telescope - Why has the Earth-Sun libration point L1 been chosen over L2 for NEOCam to detect new NEOs?

above: Profoundly not-to-scale illustration of NEOCam in an orbit around the Sun-Earth libration point L1, about 1.5 million kilometers from Earth. Presumably Sun-shield and Earth-shield block light (both infrared and visible) from the Sun and the Earth in order for the instrument to work at cold temperature necessary to detect the faint infrared light radiated from NEOs.above: Infrared astronomer Amy Mainzer illustrates how asteroids warmed by the sun will stand out more brightly in the infrared compared to reflected visible light from the sun...Read more

lagrangian points - What was the probability that Osiris Rex would find Earth Trojans?

Orbits at the Sun-Earth L4 and L5 (where Earth-associated Trojan asteroids might reside) are not long term stable due to Jupiter's large perturbing effects.Jupiter is about 318 times more massive than Earth but only 4.2 to 6.2 times further away from these points than at its closest/farthest distance than Earth (5.2-1, 5.2+1 AU vs 1 AU).Since force is proportional to mass divided by distance squared, Jupiter will exert a force between about 18 and 8 times larger (respectively) than Earth does at these points. This would on any normal celestial ...Read more