<p>I'm afraid not. The umbral limit for Mercury will vary (as a result of Mercury's eccentric orbit) but is about 170,000 km from the planet.  The Lagrange point (again it moves due to the non-circular orbit) is about <span class="math-container">$R(\mu/3)^{1/3}$</span>, where R is the Mercury-sun distance and <span class="math-container">$\mu$</span> is the mass ratio.  That gives a Lagrange point that is about 2500,000 km from Mercury. An order of magnitude greater.</p>
<p>Human exploration of Mercury is probably unlike in the foreseeable future.  It's also probably not a very interesting place for humans to visit in person.  Mercury is one for the robots.</p>

CC BY-SA 4.0
2024-05-13T11:05:01.567Z
+1, further reading: [...the Sun-Mercury libration points (all five of them) are merely mathematical curiosities of a hypothetical two-body system. ...the actual gravitational effects of Venus and Earth (both much larger than Mercury, but also farther away) make the two-body approximation "less than useful" for any real world systems.](https://space.stackexchange.com/a/22417/12102)
uhoh
CC BY-SA 4.0
2024-05-12T16:31:16.300Z
2024-05-12T16:31:16.300Z
James K
<p>Or is it just too far away to be shadowed from the photosphere of the sun?</p>
<p>Just wondering if some futuristic science/observation station could ever be placed there.</p>
<p>I know about the polar craters that are always dark.  Otherwise it looks like Mercury is beyond a human visit.</p>

<mercury><lagrange-point>
Is there an L2 Lagrange point for Mercury that lies in the shadow?
robert bristow-johnson
# Is there an L2 Lagrange point for Mercury that lies in the shadow?

(Asked by: username_0 on 2024-05-12)

Or is it just too far away to be shadowed from the photosphere of the sun?

Just wondering if some futuristic science/observation station could ever be placed there.

I know about the polar craters that are always dark. Otherwise it looks like Mercury is beyond a human visit.

**Tags:** mercury, lagrange-point

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## 1 answers

### Answer by username_1 on 2024-05-12. Score: 7 | Accepted answer

I'm afraid not. The umbral limit for Mercury will vary (as a result of Mercury's eccentric orbit) but is about 170,000 km from the planet. The Lagrange point (again it moves due to the non-circular orbit) is about $R(\mu/3)^{1/3}$, where R is the Mercury-sun distance and $\mu$ is the mass ratio. That gives a Lagrange point that is about 2500,000 km from Mercury. An order of magnitude greater.

Human exploration of Mercury is probably unlike in the foreseeable future. It's also probably not a very interesting place for humans to visit in person. Mercury is one for the robots.

> **Comments:**
> **username_2**: +1, further reading: [...the Sun-Mercury libration points (all five of them) are merely mathematical curiosities of a hypothetical two-body system. ...the actual gravitational effects of Venus and Earth (both much larger than Mercury, but also farther away) make the two-body approximation "less than useful" for any real world systems.](https://space.stackexchange.com/a/22417/12102)  

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