SpaceX filed an application with the US Federal Communications Commission for a megaconstellation of up to one million #satellites to power data centres in #space.

The proposal envisions satellites operating between 500 and 2,000 kilometres in low Earth #orbit. Some of the orbits are designed for near-constant exposure to sunlight.

The approval process for these satellites focuses almost entirely on the limited technical info companies have to submit to regulators.

Cultural, spiritual, and most #environmental impacts aren’t taken into account – but they should be.

At this scale of growth, the night #sky will change permanently and globally for generations to come.

In 2021, astronomers estimated that in less than a decade, 1 in every 15 points of light in the night sky would be a moving satellite. That estimate only included the 65 000 #megaconstellation satellites proposed at the time.

Once deployed at a scale of millions, the impacts on the night sky may not be easily reversed.

#astronomy
https://theconversation.com/too-many-satellites-earths-orbit-is-on-track-for-a-catastrophe-but-we-can-stop-it-275430

Some 700 million years ago, #Earth would have looked like a blinding white #snowball.

During the #Cryogenian period, from 720 million to 635 million years ago, the Earth was buried by massive ice sheets that marched from the poles to the tropics.

Surface temperatures were as low as -50°C.

Because the bright, white surface of the #planet reflected the Sun’s energy – a phenomenon known as the albedo effect – the Earth remained locked in this extreme climate state for tens of millions of years.

This seems an unlikely cradle for #life, yet new evidence suggests the frozen #ocean featured restricted ice-free oases that provided a lifeline for our earliest complex ancestors.

#astrobiology #planets
https://theconversation.com/snowball-earth-wasnt-fully-frozen-ice-free-oases-sheltered-early-life-275240

For #life to develop on a #planet, certain chemical elements are needed in sufficient quantities.

#Phosphorus is vital for the formation of DNA and RNA, which store and transmit genetic information, and for the energy balance of cells.

#Nitrogen is an essential component of proteins, which are needed for the formation, structure, and function of cells.

Without these two elements, no life can develop out of lifeless matter but there are also more profound consequences.

During the formation of a #planet's core, there needs to be exactly the right amount of oxygen present so that phosphorus and nitrogen can remain on the surface of the planet.

This was exactly the case with Earth around 4.6 billion years ago—a stroke of chemical good fortune in the #universe.

When #planets form, they initially develop out of molten rock.

A sorting process occurs during this time: heavy metals such as iron sink down and form the core, while lighter metals form the mantle and the crust.

If there is too little #oxygen present during the formation of the core, phosphorus will fuse with heavy metals such as iron and move to the core.

This element is then no longer available for the development of life.

On the other hand, too much oxygen present during core formation leads to phosphorus remaining in the mantle and #nitrogen being more likely to escape into the #atmosphere, ultimately being lost.

#astronomy #astrobiology
https://phys.org/news/2026-02-small-planets-suitable-life.html

Paper by Walton et al. (2026):
https://www.nature.com/articles/s41550-026-02775-z