Showing posts with label Soil. Show all posts
Showing posts with label Soil. Show all posts

Friday, August 28, 2026

What are the most exotic soil compositions discovered or theorized on exoplanets?

 On extreme exoplanets, the "soil" isn't made of dirt. The ground beneath your feet could be an ocean of boiling magma, bare volcanic rock, or freshly fallen rock snow.

For years, astronomers theorized that the super-Earth 55 Cancri e was a "diamond planet" with a mantle of carbon and a surface crusted in graphite and diamond.

An illustration of 55 Cancri e, a super-Earth with a surface completely covered by a molten magma ocean. Photo by Kevin M. Gill is licensed under CC BY 2.0.

However, recent observations by the James Webb Space Telescope (JWST) have challenged this carbon-rich model. Rather than a solid diamond crust, the surface is a global magma ocean shrouded by an atmosphere containing carbon monoxide or carbon dioxide. Any solid ground that briefly cools into a crust is transient, inevitably sinking back into the global lava sea.

On the rocky lava world K2-141b, the "soil" on the planet's nightside is continuously replenished by literal rock storms. The intense heat on the star-facing hemisphere vaporizes the crust itself, forming a thin atmosphere of gaseous minerals like silicon and sodium. Supersonic winds drag these mineral vapors across the terminator line to the dark side, where temperatures plunge to frigid extremes. The vapor condenses and falls as rocky snow and rain, burying the nightside in freshly precipitated mineral drifts. This silicate soil is eventually pulled back into the dayside magma ocean by fluid currents to restart the cycle.

Some exoplanetary surfaces resemble Earth’s volcanic regions but exist entirely without an atmosphere. The rocky exoplanet LHS 3844b orbits its star so closely that any atmospheric gases have been stripped away. Infrared data suggests its solid, dark surface is composed almost entirely of low-silica materials like volcanic basalt or olivine. Without air, water, or wind to erode it, the crust remains a stark, unweathered expanse of volcanic rock, left exposed to the vacuum of space.

Saturday, November 15, 2025

Is it true that Indian soil is too soft for bullet trains? Why?

 India is a vast country with varied landscapes and topography and the soil varies from region to region place to place.

Painting the entire landmass of India with one brush and characterizing its soil type as a monolithic is not really smart. The soil varies from place to place.

This is the Qinghai railway. Connects Beijing with Lhasa.

it’s currently the highest railway in the world.

550 kms of the Qinghai railway is built on Permafrost.

Go do research on constructing anything on permafrost.

While not a high speed railway, the challenges of constructing a railway on permafrost is way more challenging.

Both Russia and China have railways built on permafrost and the construction is way more challenging as you have to reinforce the ground underneath before you can build on it and make sure the hardened soil doesn’t melt away.

So as you can see, even if I were to take your assumption of a monolithic soil type in entire India, engineering can overcome it and I highly doubt your premise is correct.

Manhattan in NYC has glacial till soil as top layer and so does many other boroughs.

This is the Manhattan skyline

How did they construct the skyscrapers?

By going deep into the ground till they hit bedrock where they can anchor the pillars that support the structure.