in Space#

Intro catchy phrase

In the vastness of space, where darkness abounds,
And the stars shine bright with no earthly sounds,
There’s a beauty, found in the depths of the void,
Where water ice crystals are ubiquitously deployed.

Far from the warmth of the sun’s bright rays,
In the cold, dark regions, the ice crystals play,
A pristine beauty, frozen and still,
A sight that’s majestic, serene, and chill.

In the far-off planets, beyond our own,
Where ice is abundant, and life’s unknown,
Water ice covers the surfaces with grace,
And shines like diamonds in the depths of space.

From the rings of Saturn to Pluto’s frozen plains,
The beauty of water ice forever reigns,
A marvel of nature, pure and bright,
A breathtaking sight that’s out of sight.

So let us gaze upon the cosmic skies,
And marvel at the beauty that meets our eyes,
Water ice in space, a sight to behold,
A wondrous sight that never grows old.

– Vince (& ChatGPT)



Change image!


Water Molecule

Condensed phase

Water Models

Hexagonal Ice

Ice doesn’t form in space like on Earth. Actually the type of ice we will speak about doesn’t naturally occur at the Earth surface.


  • Interstellar dust

    • Formation

    • Evolution

    • Processing

    • Observation

  • Where ?

    • Protoplanetary disks

    • Solar System

    • ISM

  • In the laboratory

Key Litterature:

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  • 2


  • 1

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Molecules in space#

Water is the most abundant solid-state molecule in space [Öberg et al., 2011],

  • insert list of molecules detected

  • Different space environments (scope is within the galaxy)

    • Circumstellar shells

    • ISM

      • Diffuse ISM

      • Molecular clouds

    • Protoplanetary Disk

    • Comets

    • Planets and solar system icy bodies

Some molecules have been detected in comets but not in the ISM.

  • Insert table of space conditions in the ISM environments

Most of them have been detected into the gas phase (from radio astronomy: ALMA) but How do they form

  • At the surface of micrometer dust

Interstellar Dust#

» Formation


Star Death


Atomic Deposition

Insert video about dust forming

» Evolution

Insert diagram

The Dust cycle in the galaxy

Is it a layerd system or is the ice and dust mixed ?

Grain growth

Check P.M. Bellan group papers (Caltech)

» Processing

Ice form around interstellar dust grains that are less than 1 µm in size like shown in figure X. Let’s pause for a second and have a closer look at those because despite their size, they play a gigantic role in the story of the universe.

Dust grain


» Infrared telescope

Spatial telescopes to avoid atmosphere absorbtion. Target the 3µm ice band .










[Boogert et al., 2008]






» How does it work ?

Molecular Absorption Spectrum


IR Signatures:

  • H20

  • NH3

  • SiO2

Dartois sub 3


[McClure et al., 2023]

» The 3µm Ice band

More Spectrum (Amorphous Crystaline)

Water as a tracer of Interstellar processes#

Molecular synthesis#

» In space

We stated on the previous chapter (link) that ASW doesn’t occure naturally on earth but can we find it in space ? Yes, here is where

Molecular Clouds

Protoplanetary Disks

Temperature gradient (mxture). Evolution with time (energetic events - Star Outburst …)

Snow line

» Solar Systems


In the laboratory#

Yes, we can produce little volume of space in my lab. Using a high vaccum chamber …

  • link to method

The ice today#