"Rains glass"? What does it mean?

[NewHope]

Rain glass means weatherglass when used as a noun phrase. But what does it mean when used as a verb?
Context:
If seen directly it would look like a "deep blue dot," reminiscent of Earth's color as seen from space. But that's where all comparison ends. The planet's daytime atmosphere is nearly 2,000 degrees Fahrenheit, and it possibly rains glass -- sideways -- in howling 4,500-mile-per-hour winds.

More:
Hubble finds a true blue planet: Giant Jupiter-sized planet located 63 light-years away

 

[MikeNewYork]

Rain glass means weatherglass when used as a noun phrase. But what does it mean when used as a verb?
Context:
If seen directly it would look like a "deep blue dot," reminiscent of Earth's color as seen from space. But that's where all comparison ends. The planet's daytime atmosphere is nearly 2,000 degrees Fahrenheit, and it possibly rains glass -- sideways -- in howling 4,500-mile-per-hour winds.

More:
Hubble finds a true blue planet: Giant Jupiter-sized planet located 63 light-years away

This is referring to raining glass as an analogy to raining water on earth. Glass is made from the appropriate raw materials and intense heat.

 

[emsr2d2]

The planet they found appears to have a weather phenomenon very similar to the rain that falls on Earth, but instead of the rain consisting of water, it is made up of tiny shards of glass.