The Space Thread

[Tenkaykev]

Prelude did a better version .

Heresy!

 

[Tenkaykev]

Coincidentally the Ars weekly Rocket Report just dropped so I'll post a link.
I'm a subscriber so don't see any ads, apologies if the interface is cluttered for non subscribers.

https://arstechnica.com/space/2023/...rtment-sues-spacex-north-korean-launch-fails/

 

[Jody]

I've been able to see the Milky Way from my back garden over the last week. Didn't think it would be possible where I lived as we're semi rural but I checked the constellations on my phone and then googled a couple of sky photos and sure enough my eyes weren't deceiving me.

It's been a good few weeks looking upwards at night. The Perseids meteor shower put on a good show. Some of them were unreal intensity and were leaving what I assume were smoke trails behind them.

 

[Profpointy]

I'm a bit of a Space geek and subscribe to a few YouTube channels ( Nasa Space Flight, Scott Manley , Marcus House ) I also subscribe to Ars Technica " who's Eric Berger and a colleague write an excellent weekly " Rocket Report " as well as several other space related articles. The comments on the articles on Ars are particularly insightful as the contributors are often working in a relevant field and are happy to explain and clarify any misconceptions. There's also an excellent book which is in the Public Domain called " Ignition " about the early days of Rocket Fuel research, the scientists were outstandingly brave and absolutely bonkers with some of the risks they took. Finally, this thread inspired me to wander over to the CD rack and put on the excellent " After the Goldrush " album by Neil Young.🎶

Well, I dreamed I saw the silver space ships flying
In the yellow haze of the sun.
There were children crying and colors flying
All around the chosen ones.

All in a dream, all in a dream
The loading had begun.

Flying Mother Nature's silver seed to a new home in the sun.
Flying Mother Nature's silver seed to a new home.

"Ignition" is an amazing book. It concerns the chemistry of rocket fuels. I seem to recall one oxidising agent so reactive that concrete burns explosively with it

 

[Drago]

The difference between oxidisers and fuels is an important technical and legal one. Once that's clicked in your mind you're well on the way.

 

[classic33]

https://spacecoastlaunches.com/launch-list/

 

[Mad Doug Biker]

From Buzz Aldrin's Facebook page:

https://m.facebook.com/story.php?st...TtEwh1aWCdnqCgcmi8UZL6n6ml&id=100044331344607

"Well, according to new photography captured by the #NASA Lunar Reconnaissance Orbiter, the Moon is now sporting a new crater! It’s the imprint left from the Luna 25 crash a few weeks ago. Of course, the number of craters on the Moon is always changing, but the Lunar surface is pockmarked with tens and tens of thousands of craters, many of which are several miles across. Needless to say, that old rock certainly has a lot of scars!"

 

[Mad Doug Biker]

So, can someone tell me... Why do scientists like Brian Cox always smugly tell us that no matter where you are in the Universe, you need water for life?
That's only life as we know it!

How can they 'know'? Have they met an alien? They could drink battery acid for all we know! 🤷


I don't get how they supposedly 'know'.

 

[Mad Doug Biker]

And there it is:

 

[Mad Doug Biker]

So, can someone tell me... Why do scientists like Brian Cox always smugly tell us that no matter where you are in the Universe, you need water for life?
That's only life as we know!

How can they 'know'? Have they met an alien? They could drink battery acid for all we know! 🤷


I don't get how they supposedly 'know'.

I'm surprised that one of you 'experts' hasn't answered.

 

[newfhouse]

I'm surprised that one of you 'experts' hasn't answered.

Some clues here.

https://astrobiology.nasa.gov/education/alp/water-so-important-for-life/

All life on this planet needs water to survive. Some life can live with very little water in extremely dry places but they still need water. As we strive to find life beyond Earth, it is important to consider what life on Earth tells us about where to look. Why is water so important for life? Water supports cell functions. All organisms are made of cells, from microbes to the largest animals. All of life’s functions are completed within cells. Life needs chemical reactions to take place in order to gain energy, grow, and get rid of waste. Water is a liquid which allows the chemistry of life to take place. It is also a polar molecule which allows most other molecules to be dissolved. Because of this, we call water a “solvent”. Having such a good solvent as water is critical for the functions of life. But there are also some other reasons why water is so important:

Water is plentiful! Hydrogen is the most plentiful element in the universe and oxygen the most plentiful in Earth’s crust. On Earth, about 70% of the surface is covered by water. But there’s also lots of water in other places in our solar system. For instance, we’ve found many lines of evidence that lots of water existed on the surface of Mars during its early times, and Mars currently has a lot of frozen water under its surface. Comets contain mostly water ice. There are lots of moons in our solar system that are made of a lot of water ice, and there are even some moons with liquid water oceans under their icy crusts (like Europa and Enceladus).

Water still has other advantages as a solvent for life. For instance, water stays in the liquid phase over a large range of temperatures compared to some other solvents. That allows more places to have the potential for liquid water. It also has a high heat capacity. This means that water offers some protection to organisms from quick or drastic temperature changes.

Water also has an interesting property with regard to the density of ice. For many molecules, the solid has a higher density than the liquid. So, for most molecules, the solid would sink in the liquid. But this isn’t the case with water. For water, ice is actually less dense than liquid water. This is why ice floats! If this didn’t happen, then all of the organisms that live in the bottoms of lakes in the winter time would be completely frozen. But, even worse, during times in our planet’s history when the world has become very cold (causing what we call Snowball Earth), if frozen water sank, then all of Earth’s ocean life would have become frozen and maybe died!

If we want to understand how life works, then it’s really important to understand the chemistry of water. And astrobiologists who are wondering if we’re alone in the universe need to be aware of the potential for water to be important for other kinds of life as well. Right now, we’re investigating worlds like Enceladus and Europa, Mars, and other solar system bodies that show signs of water. Also, beyond our solar system, we’re looking for exoplanets that have the potential for liquid water at their surfaces, since they might be important places for us to look for possible extraterrestrial life.

 

[Mad Doug Biker]

Some clues here.

https://astrobiology.nasa.gov/education/alp/water-so-important-for-life/

All life on this planet needs water to survive. Some life can live with very little water in extremely dry places but they still need water. As we strive to find life beyond Earth, it is important to consider what life on Earth tells us about where to look. Why is water so important for life? Water supports cell functions. All organisms are made of cells, from microbes to the largest animals. All of life’s functions are completed within cells. Life needs chemical reactions to take place in order to gain energy, grow, and get rid of waste. Water is a liquid which allows the chemistry of life to take place. It is also a polar molecule which allows most other molecules to be dissolved. Because of this, we call water a “solvent”. Having such a good solvent as water is critical for the functions of life. But there are also some other reasons why water is so important:

Water is plentiful! Hydrogen is the most plentiful element in the universe and oxygen the most plentiful in Earth’s crust. On Earth, about 70% of the surface is covered by water. But there’s also lots of water in other places in our solar system. For instance, we’ve found many lines of evidence that lots of water existed on the surface of Mars during its early times, and Mars currently has a lot of frozen water under its surface. Comets contain mostly water ice. There are lots of moons in our solar system that are made of a lot of water ice, and there are even some moons with liquid water oceans under their icy crusts (like Europa and Enceladus).

Water still has other advantages as a solvent for life. For instance, water stays in the liquid phase over a large range of temperatures compared to some other solvents. That allows more places to have the potential for liquid water. It also has a high heat capacity. This means that water offers some protection to organisms from quick or drastic temperature changes.

Water also has an interesting property with regard to the density of ice. For many molecules, the solid has a higher density than the liquid. So, for most molecules, the solid would sink in the liquid. But this isn’t the case with water. For water, ice is actually less dense than liquid water. This is why ice floats! If this didn’t happen, then all of the organisms that live in the bottoms of lakes in the winter time would be completely frozen. But, even worse, during times in our planet’s history when the world has become very cold (causing what we call Snowball Earth), if frozen water sank, then all of Earth’s ocean life would have become frozen and maybe died!

If we want to understand how life works, then it’s really important to understand the chemistry of water. And astrobiologists who are wondering if we’re alone in the universe need to be aware of the potential for water to be important for other kinds of life as well. Right now, we’re investigating worlds like Enceladus and Europa, Mars, and other solar system bodies that show signs of water. Also, beyond our solar system, we’re looking for exoplanets that have the potential for liquid water at their surfaces, since they might be important places for us to look for possible extraterrestrial life.

Thanks, that has bugged me for years!

 

[Mad Doug Biker]

THE LINK IS AT THE BOTTOM! 🙄🙄🙄🙄:


View: https://www.facebook.com/reel/9870136926393907?fs=e&s=TIeQ9V

 

[classic33]

Scientists believe an asteroid the size of the Empire State Building could hit Earth

 

[Mad Doug Biker]

Scientists believe an asteroid the size of the Empire State Building could hit Earth

2182? I'd be 200 years old! 😆