<p><a href="https://www.nasa.gov/mission_pages/WISE/main/index.html" rel="nofollow noreferrer">WISE or Wide-Field Infrared Survey Explorer</a></p>

<p>Large body collisions are obviously, very very rare, locally speaking, and with stars, often spiraling inwards not direct collisions.  I know that stellar collisions or gradual inward spirals have been observed, but those are much larger and easier to see from far away.</p>

<p>If an impact, like Theia-Earth happened in another solar-system, creating perhaps <a href="https://www.sciencedaily.com/releases/2018/02/180228103238.htm" rel="nofollow noreferrer">a synestia</a> or spiraling rock-vapor world, approaching some star's surface temperature, can we say about how close that would need to be to be observed with today's instruments?</p>

<p>Would the outer-most debris cool too quickly and block a lot of the visibility?</p>

<p>My guess is, events like this would be too infrequent to happen within our view, so we shouldn't expect to observe it until we have much better telescopes, but other events weren't expected to be observed, like the gravitational waves from two colliding black holes and that was detected.  </p>

<p>If it was close enough the heat from collision and rate of cooling should create a unique signature I would think, so if a planet-planet collision did happen in our general vicinity, we'd recognize it for what it was.</p>

CC BY-SA 4.0
2019-09-03T10:14:05.070Z
I don't know about the event itself, but those debris fields are easily visible.
SpaceCore
CC BY-SA 4.0
2019-09-03T12:29:19.047Z
@SpaceBread certainly if the debris field transits it's star.   I'm not sure a debris field would be visible if it didn't transit.
userLTK
CC BY-SA 4.0
2019-09-03T12:52:19.453Z
The IR emission from the dust and gas would also be seen if the disk is not transiting in front of the star. See here: https://ui.adsabs.harvard.edu/abs/2009ApJ...701.2019L
SpaceCore
<exoplanet><collision>
Would the WISE Survey pick up a large planetary collisions like Theia-Earth? And from how far?
userLTK
# Would the WISE Survey pick up a large planetary collisions like Theia-Earth? And from how far?

(Asked by: username_0 on 2019-09-02)

[WISE or Wide-Field Infrared Survey Explorer](https://www.nasa.gov/mission_pages/WISE/main/index.html)

Large body collisions are obviously, very very rare, locally speaking, and with stars, often spiraling inwards not direct collisions. I know that stellar collisions or gradual inward spirals have been observed, but those are much larger and easier to see from far away.

If an impact, like Theia-Earth happened in another solar-system, creating perhaps [a synestia](https://www.sciencedaily.com/releases/2018/02/180228103238.htm) or spiraling rock-vapor world, approaching some star's surface temperature, can we say about how close that would need to be to be observed with today's instruments?

Would the outer-most debris cool too quickly and block a lot of the visibility?

My guess is, events like this would be too infrequent to happen within our view, so we shouldn't expect to observe it until we have much better telescopes, but other events weren't expected to be observed, like the gravitational waves from two colliding black holes and that was detected.

If it was close enough the heat from collision and rate of cooling should create a unique signature I would think, so if a planet-planet collision did happen in our general vicinity, we'd recognize it for what it was.

**Tags:** exoplanet, collision

> **Comments:**
> **username_1**: I don't know about the event itself, but those debris fields are easily visible.  
> **username_0**: @SpaceBread certainly if the debris field transits it's star.   I'm not sure a debris field would be visible if it didn't transit.  
> **username_1**: The IR emission from the dust and gas would also be seen if the disk is not transiting in front of the star. See here: https://ui.adsabs.harvard.edu/abs/2009ApJ...701.2019L  

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## 0 answers

