<p>It looks to me that you probably have some misunderstanding of the term meteorite. A meteorite is a remnant body which has reached the surface of a major or minor body (a planet, a moon, an asteroid, etc.). The meteorite's parent body (a meteoroid) would definitely lose its entire water ice (if it had any at all) no later than during its passage through the Earth's atmosphere. That's why no water ice was or will ever be found in meteorites.</p>

<p>So, unless you compare common meteorite impacts with hazardous asteroid impacts, these two body types are incomparable as water ice carriers. And thus, the statement by O'Brien et al still stands firm and will do so ever.</p>

CC BY-SA 4.0
2018-08-17T04:07:04.577Z
O'Brien also states "In addition, water vapor has been discovered coming from Ceres (Kuppers et al., 2014) and water ice has been observed on the surface of Themis (Campins et al., 2010, Rivkin and Emery, 2010), suggesting that the water content of primitive asteroids, small and large, is substantially larger than that recorded in meteorites."  Do you agree with this statement? He seems to be comparing the water content on meteorites and asteroids.
Bell
CC BY-SA 4.0
2018-08-17T04:28:06.517Z
Of course, you can compare water content on any types of bodies in general; so, yes, I agree with him. But in my answer I meant something different, that this comparison is obviously meaningless if you try to figure out which of the two bodies could have brought water on Earth. It is an obvious thing, because just imagine bodies ranging from grain-sized meteoroids up to Ceres-sized asteroids: theoretically only a huge asteroid's remnant mass could still have some water ice inclusions after the impact (I'd doubt that, though), while a common meteorite would never have it simply due to its size.
SergiusPro
CC BY-SA 4.0
2018-08-17T06:43:59.190Z
Has water ice been found on comets? Or is this unique to larger bodies, like asteroids?
Bell
CC BY-SA 4.0
2018-08-17T14:16:21.010Z
Yes, there is a plenty of water ice and other ice types in/on comets. Any solid space body can have it to a larger or smaller degree.
SergiusPro
CC BY-SA 4.0
2018-08-17T17:00:49.603Z
@Bell - A larger object has the **potential** to carry more water and an object burning up in the atmosphere was no potential to have surface ice; though past or present H$_2$O may be detected. Japan is landing on asteroid Ryugu, see the [Haya2kun Twitter](https://twitter.com/haya2kun) they have almost landed. It appears dry. Maybe there's a bit of ice, it may not be water ice, or maybe there's no ice at all; each are different. NASA's article: "[Asteroid or Meteor: What's the difference?](https://spaceplace.nasa.gov/asteroid-or-meteor/en/)" - see their  https://www.asteroidmission.org/ .
Rob
CC BY-SA 4.0
2018-08-17T23:44:28.933Z
Okay thanks, this has helped me a lot. Could water ice on a comet survive entering Earth's atmosphere? Also, I was just reading about carbonaceous chondrites and their contribution to Earth's water supply. I'm guessing they too could not hold water ice? Every journal articles/website etc doesn't seem to draw a distinction between water and ice and water bounded with silicates (e.g. meteors).
Bell
CC BY-SA 4.0
2018-08-18T00:43:16.567Z
Well, comets' density is very very low. So, at least a comet would disrupt during its atmospheric passage. Hence we can only ask, if any of the icy remnants could reach the surface, not the entire nucleus. Hm, for that it must be a huge comet. An average comet with diameter of 5-6 km wouldn't manage it. A comet similar in size to the Hale-Bopp comet (d = 40-80 km) probably could, but I doubt even that. And as for the chondrites, it doesn't matter which type of a meteorite it is, they all will never have water ice.
SergiusPro
CC BY-SA 4.0
2018-08-18T01:40:01.267Z
@Bell "Could water ice on a comet survive entering Earth's atmosphere?" The ice is vaporised on entry, but the water *molecules* survive and become part of the atmosphere.
Chappo Hasn't Forgotten
CC BY-SA 4.0
2018-08-18T03:11:59.153Z
Have we sampled any asteroids to determine their water D/H ratio?
Bell
CC BY-SA 4.0
2018-08-17T03:41:41.000Z
2018-08-17T03:41:41.000Z
SergiusPro
<p>Turner McGee et al. 2021: Carbonaceous chondrite meteorites experienced fluid flow within the past million years. Science 10.1126/science.abc8116</p>
<p>“And thus, the statement by O'Brien et al still stands firm and will do so ever.” -SerguisPro</p>
<p>Two years and five months, an eternity in pro geochemistry.</p>

CC BY-SA 4.0
2022-08-16T15:41:12.297Z
2022-08-16T15:41:12.297Z
caInstrument
<p>I was reading an article by David O'Brien et al. where it stated</p>

<blockquote>
  <p>"in meteorites only the water bound to the silicates can be found, all the water ice having been lost, whereas on asteroids water ice itself has been detected"</p>
  
  <p><a href="https://www.sciencedirect.com/science/article/pii/S0019103514002620" rel="nofollow noreferrer">https://www.sciencedirect.com/science/article/pii/S0019103514002620</a></p>
</blockquote>

<p>Now this was published in 2014, so I'm wondering what is the validity of this statement today. Have we, since the publication of this article, discovered water ice on meteorites?</p>

<earth><asteroids><meteorite><water>
Water Ice on Meteorites
Bell
# Water Ice on Meteorites

(Asked by: username_0 on 2018-08-17)

I was reading an article by David O'Brien et al. where it stated

> "in meteorites only the water bound to the silicates can be found, all the water ice having been lost, whereas on asteroids water ice itself has been detected"
>
> <https://www.sciencedirect.com/science/article/pii/S0019103514002620>

Now this was published in 2014, so I'm wondering what is the validity of this statement today. Have we, since the publication of this article, discovered water ice on meteorites?

**Tags:** earth, asteroids, meteorite, water

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## 2 answers

### Answer by username_1 on 2018-08-17. Score: 5 | Accepted answer

It looks to me that you probably have some misunderstanding of the term meteorite. A meteorite is a remnant body which has reached the surface of a major or minor body (a planet, a moon, an asteroid, etc.). The meteorite's parent body (a meteoroid) would definitely lose its entire water ice (if it had any at all) no later than during its passage through the Earth's atmosphere. That's why no water ice was or will ever be found in meteorites.

So, unless you compare common meteorite impacts with hazardous asteroid impacts, these two body types are incomparable as water ice carriers. And thus, the statement by O'Brien et al still stands firm and will do so ever.

> **Comments:**
> **username_0**: O'Brien also states "In addition, water vapor has been discovered coming from Ceres (Kuppers et al., 2014) and water ice has been observed on the surface of Themis (Campins et al., 2010, Rivkin and Emery, 2010), suggesting that the water content of primitive asteroids, small and large, is substantially larger than that recorded in meteorites."  Do you agree with this statement? He seems to be comparing the water content on meteorites and asteroids.  
> **username_1**: Of course, you can compare water content on any types of bodies in general; so, yes, I agree with him. But in my answer I meant something different, that this comparison is obviously meaningless if you try to figure out which of the two bodies could have brought water on Earth. It is an obvious thing, because just imagine bodies ranging from grain-sized meteoroids up to Ceres-sized asteroids: theoretically only a huge asteroid's remnant mass could still have some water ice inclusions after the impact (I'd doubt that, though), while a common meteorite would never have it simply due to its size.  
> **username_0**: Has water ice been found on comets? Or is this unique to larger bodies, like asteroids?  
> **username_1**: Yes, there is a plenty of water ice and other ice types in/on comets. Any solid space body can have it to a larger or smaller degree.  
> **username_2**: @Bell - A larger object has the **potential** to carry more water and an object burning up in the atmosphere was no potential to have surface ice; though past or present H$_2$O may be detected. Japan is landing on asteroid Ryugu, see the [Haya2kun Twitter](https://twitter.com/haya2kun) they have almost landed. It appears dry. Maybe there's a bit of ice, it may not be water ice, or maybe there's no ice at all; each are different. NASA's article: "[Asteroid or Meteor: What's the difference?](https://spaceplace.nasa.gov/asteroid-or-meteor/en/)" - see their  https://www.asteroidmission.org/ .  
> **username_0**: Okay thanks, this has helped me a lot. Could water ice on a comet survive entering Earth's atmosphere? Also, I was just reading about carbonaceous chondrites and their contribution to Earth's water supply. I'm guessing they too could not hold water ice? Every journal articles/website etc doesn't seem to draw a distinction between water and ice and water bounded with silicates (e.g. meteors).  
> **username_1**: Well, comets' density is very very low. So, at least a comet would disrupt during its atmospheric passage. Hence we can only ask, if any of the icy remnants could reach the surface, not the entire nucleus. Hm, for that it must be a huge comet. An average comet with diameter of 5-6 km wouldn't manage it. A comet similar in size to the Hale-Bopp comet (d = 40-80 km) probably could, but I doubt even that. And as for the chondrites, it doesn't matter which type of a meteorite it is, they all will never have water ice.  
> **username_3**: @Bell "Could water ice on a comet survive entering Earth's atmosphere?" The ice is vaporised on entry, but the water *molecules* survive and become part of the atmosphere.  
> **username_0**: Have we sampled any asteroids to determine their water D/H ratio?  

---

### Answer by username_4 on 2022-08-16. Score: 1

Turner McGee et al. 2021: Carbonaceous chondrite meteorites experienced fluid flow within the past million years. Science 10.1126/science.abc8116

“And thus, the statement by O'Brien et al still stands firm and will do so ever.” -SerguisPro

Two years and five months, an eternity in pro geochemistry.


---

