“It’s very hard to form planets this fluffy,” says Yale astronomer Tiger Lu, lead author on the new work. “The standard idea of gas planet formation is that planets start as rocky cores, which then gravitationally attract and accrete gas from their surroundings…It turns out that in this standard model, it’s almost impossible to accrete enough gas to create the gas to rock ratio necessary for these cotton-candy like worlds.”

Super-puffs close to their stars are likely the result of the star heating up the planet’s atmosphere and fluffing it up. But there are a few strange super-puffs too far from their stars for this heating to work. One example is the planet HIP-41378 f, a gas giant with a three year orbit around an almost Sun-like star about 350 light years away from Earth. “None of the accepted puffing mechanisms are even remotely possible” for this world, explains Lu. 

It’s important to note that the supposed ultra-low densities of cotton candy worlds come from measurements of transit depth, the amount of light that a planet blocks when it passes in front of its star. This quantity is proportional to how big the planet is—a bigger planet blocks out more light, and vice versa. But what if the planet isn’t actually that big, and there’s something else in the way blocking out that light?

“Both rings and moons are common among sufficiently large planets in our Solar System,” explains Yoni Brande, a University of Kansas astronomer not involved in the new study. “So why shouldn’t we try and see if they can explain some of the weird exoplanet data we’ve already got?”

Lu’s work shows that HIP-41378 f has been kicked around by gravity, tilting it on its side and conveniently making the rings visible to us in a way that would make the planet appear bigger when it transits. “If the planet were not tilted, we would view these thin rings edge-on and barely be able to see them,” says Lu. 

Interestingly, planets really close to their stars couldn’t be tilted in the same way, meaning those particular super-puffs are likely explained by the more traditional ideas of heating instead of rings. “So, the further away a super-puff is from its host star the more likely the ring hypothesis is,” adds Lu.

At the same time the idea of digital money appeared. The main value of the concept was reduced to the possibility of quick purchase of shares, various financial assets and their derivatives.

At that time, American cryptographers David Chaum and Stephan Brands worked on the realization of the idea of electronic money. They described the principles of an anonymous digital payment system and proposed the first “electronic cash” protocols.

In 1990, David and Stephan created DigiCash, a company that specialized in the development and implementation of the eCash money system. It had a feature to support the privacy of electronic payments and cryptographic data protection was present.

The main difference between eCash and modern cryptocurrencies was centralized management. In 1998, this platform went bankrupt. But the very idea of using fast anonymous payments was noticed by many cryptocurrencies.

A significant contribution to the formation of cryptocurrency was made by Adam Bakov. It was he who in 1997 applied HashCash - a technology resistant to spam and DoS-attacks. Later, Hal Finney was engaged in its improvement. He managed to create a more advanced algorithm for controlling electronic payments. The essence of the improvement was the introduction of a chain of

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