Technology, Science and the Environment.

[whoareyaaa]

Just now, The Bear said:

I don't understand you. Are you suggesting life on Earth was from panspermia?

I'd say a more intelligent race

[leicsmac]

OK then...for the interest of @foxile5 and anyone else who wants to know - how can we tell that an object 124 light years away has chemical compounds that may have been produced by microbial life?

 

Here's a breakdown of the idea of astronomical spectroscopy.

 

Spectroscopy is the study of electromagnetic spectra - radio waves, visible light, microwaves, X-rays and all the other kinds that come from many different sources. One of the uses of this applies here.

 

For as long as we've had telescopes powerful enough to do it, we've been able to observe the light coming from distant stars all over the night sky. These stars throw out light and other EM radiation at a massive variety of wavelengths - ranging from radio waves at the longest to gamma-rays at the shortest.

 

And here's the kicker - as that light passes through gases that surround a star, or a planet or other object that has an atmosphere or emits such gases, some of that light is absorbed and some of it goes right through and comes to us - or when a particular star burning particular gas produces heat and light, it does it in particular wavelengths. That produces what is called an emission line spectrum - a pattern of EM wavelengths that is as unique to each element or compound as a fingerprint. For instance, the emission wavelengths of hydrogen - the most common element in the Universe - are 410 nm (violet), 434 nm (blue), 486 nm (blue-green), and 656 nm (red). If we see a star emitting light at those wavelengths in particular, then we know it's burning hydrogen. We know the wavelengths, we know exactly what element or compound is out there.

 

In the case of K2-18b, the James Webb Space Telescope noticed light of a particular wavelength passing through it on the way from its companion star. The emission line spectrum indicated the presence of two compounds - dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) - on that planet. The only method - or by far the most common method - of producing either of those two gases is through bacterial or plankton activity - in other words, life.

 

And that's how we think we can tell there might be life on a planet over 120 light years away.

 

I think that about covers it in brief. Would be happy to answer any other questions on the matter.

 

[SpacedX]

6 minutes ago, leicsmac said:

OK then...for the interest of @foxile5 and anyone else who wants to know - how can we tell that an object 124 light years away has chemical compounds that may have been produced by microbial life?

 

Here's a breakdown of the idea of astronomical spectroscopy.

 

Spectroscopy is the study of electromagnetic spectra - radio waves, visible light, microwaves, X-rays and all the other kinds that come from many different sources. One of the uses of this applies here.

 

For as long as we've had telescopes powerful enough to do it, we've been able to observe the light coming from distant stars all over the night sky. These stars throw out light and other EM radiation at a massive variety of wavelengths - ranging from radio waves at the longest to gamma-rays at the shortest.

 

And here's the kicker - as that light passes through gases that surround a star, or a planet or other object that has an atmosphere or emits such gases, some of that light is absorbed and some of it goes right through and comes to us - or when a particular star burning particular gas produces heat and light, it does it in particular wavelengths. That produces what is called an emission line spectrum - a pattern of EM wavelengths that is as unique to each element or compound as a fingerprint. For instance, the emission wavelengths of hydrogen - the most common element in the Universe - are 410 nm (violet), 434 nm (blue), 486 nm (blue-green), and 656 nm (red). If we see a star emitting light at those wavelengths in particular, then we know it's burning hydrogen. We know the wavelengths, we know exactly what element or compound is out there.

 

In the case of K2-18b, the James Webb Space Telescope noticed light of a particular wavelength passing through it on the way from its companion star. The emission line spectrum indicated the presence of two compounds - dimethyl sulphide (DMS) and dimethyl disulphide (DMDS) - on that planet. The only method - or by far the most common method - of producing either of those two gases is through bacterial or plankton activity - in other words, life.

 

And that's how we think we can tell there might be life on a planet over 120 light years away.

 

I think that about covers it in brief. Would be happy to answer any other questions on the matter.

 

Meanwhile, on a different subject, spectroscopic analysis is not definitively conclusive about whether Betelgeuse is in the core helium or carbon burning stage of its evolution. Some studies conclude that the star is likely in the late stage of core carbon burning, and a good candidate for the next Galactic Type II supernova. Observations of Betelgeuse's pulsation periods and changes in spectral lines during the star's dimming in 2019 and 2020 indicate material movement and shedding, further supporting the red supergiant stage and its potential for a future supernova. For a 15 solar mass star such as  Betelgeuse, the carbon burning phase may be as little as 100 years and so it may already have already have gone supernova and we don't yet know, given that we are seeing the star as it was during the reign of Edward IV and the advent of Caxton's printing press. Some astronomers contend that it is somewhere within its penultimate helium burning stage which for a star the mass of Betelgeuse, could be up to 20 million years in duration. I'd suggest ignoring clickbait You Tube or Tik Tok videos that tell you that the star is imminently about to light up the night sky. 

 

Betelgeuse is four times the distance that K2-18b is from Earth so in the case of the latter, we are only peering back in time to the reign of Edward VII and propagation of the first transatlantic radio signal. The red dwarf star that it orbits within the habitable zone, is around 2 billion years old. Perhaps in 5 billion years time when the postulated single celled organisms have evolved into advanced sentient beings that (unlike us?) avoid prematurely destroying their civilisation, instead preserving it, they may gaze at and derive measurements of our own star, by then a red giant that has long since engulfed any traces of our own. 

 

Only 6% of presently observable galaxies remain reachable meaning 94% already lie beyond our reach. So, even if we traveled at the speed of light, (which according to relativity is impossible since it would require an infinite amount of energy), currently, we’d never catch up to these galaxies. Each year, another 160 billion stars - equivalent to a major galaxy - become newly unreachable. Meanwhile, the 'unobservable universe' which encompasses all that is beyond the reach of our current technology and understanding. is postulated to be at least 250 times larger than the observable universe, or 7 trillion light-years across. The "observable universe" is defined by the distance light has traveled since the Big Bang, roughly 13.8 billion years ago. This means it's a sphere with a radius of about 46 billion light-years, meaning that we can see objects that emitted light 46 billion light-years ago, nothing further.  

 

Since the universe's expansion is demonstrably accelerating, all currently observable objects, outside the local supercluster, will eventually appear to freeze in time, while emitting progressively redder and fainter light. Apropos; objects with the current redshift z from 5 to 10, they will only be visible up to an age of 4–6 billion years. In addition, light emitted by objects currently located beyond a certain comoving distance, (about 19 gigaparsecs), will never reach Earth.

[davieG]

1 hour ago, SpacedX said:

Meanwhile, on a different subject, spectroscopic analysis is not definitively conclusive about whether Betelgeuse is in the core helium or carbon burning stage of its evolution. Some studies conclude that the star is likely in the late stage of core carbon burning, and a good candidate for the next Galactic Type II supernova. Observations of Betelgeuse's pulsation periods and changes in spectral lines during the star's dimming in 2019 and 2020 indicate material movement and shedding, further supporting the red supergiant stage and its potential for a future supernova. For a 15 solar mass star such as  Betelgeuse, the carbon burning phase may be as little as 100 years and so it may already have already have gone supernova and we don't yet know, given that we are seeing the star as it was during the reign of Edward IV and the advent of Caxton's printing press. Some astronomers contend that it is somewhere within its penultimate helium burning stage which for a star the mass of Betelgeuse, could be up to 20 million years in duration. I'd suggest ignoring clickbait You Tube or Tik Tok videos that tell you that the star is imminently about to light up the night sky. 

 

Betelgeuse is four times the distance that K2-18b is from Earth so in the case of the latter, we are only peering back in time to the reign of Edward VII and propagation of the first transatlantic radio signal. The red dwarf star that it orbits within the habitable zone, is around 2 billion years old. Perhaps in 5 billion years time when the postulated single celled organisms have evolved into advanced sentient beings that (unlike us?) avoid prematurely destroying their civilisation, instead preserving it, they may gaze at and derive measurements of our own star, by then a red giant that has long since engulfed any traces of our own. 

 

Only 6% of presently observable galaxies remain reachable meaning 94% already lie beyond our reach. So, even if we traveled at the speed of light, (which according to relativity is impossible since it would require an infinite amount of energy), currently, we’d never catch up to these galaxies. Each year, another 160 billion stars - equivalent to a major galaxy - become newly unreachable. Meanwhile, the 'unobservable universe' which encompasses all that is beyond the reach of our current technology and understanding. is postulated to be at least 250 times larger than the observable universe, or 7 trillion light-years across. The "observable universe" is defined by the distance light has traveled since the Big Bang, roughly 13.8 billion years ago. This means it's a sphere with a radius of about 46 billion light-years, meaning that we can see objects that emitted light 46 billion light-years ago, nothing further.  

 

Since the universe's expansion is demonstrably accelerating, all currently observable objects, outside the local supercluster, will eventually appear to freeze in time, while emitting progressively redder and fainter light. Apropos; objects with the current redshift z from 5 to 10, they will only be visible up to an age of 4–6 billion years. In addition, light emitted by objects currently located beyond a certain comoving distance, (about 19 gigaparsecs), will never reach Earth.

I'll have to read this later my brain could take it straight away after reading the @leicsmac explanation. 

[davieG]

Some facts about bamboo:

1.Fast Growth: Bamboo is the fastest-growing plant in the world. It has been recorded at growing 47.6 inches in 24 hours. Some species can even grow over a meter per day under optimal conditions. A new bamboo shoot reaches its full height in less than a year.

2. Oxygen Release: A grove of bamboo releases 35% more oxygen than any other tree out there.

3. Carbon Dioxide Absorption: Bamboo absorbs carbon dioxide at a rate of 17 tons per hectare every year. It can act as a valuable carbon sink given how fast the plant grows.

4. No Fertilizer Required: Bamboo doesn’t need fertilizer to grow. It can self-mulch by dropping its leaves and use the nutrients to grow.

5. Drought Resistance: Bamboos are drought-tolerant plants. They can grow in the desert.

6. Wood Replacement: Bamboos can be harvested in 3-5 years compared to the 20-30 years of most softwood trees.

7. Building Material: Bamboo is incredibly strong and sturdy. It has been used as support for concrete as well as scaffolding, bridges, and houses.

8. Soil Stability: Bamboo has a wide network of underground roots and rhizomes that prevent soil erosion.

9. Natural Air Conditioner: Bamboo cools the air surrounding it by up to 8 degrees in the summer.

10. Invasiveness: Some species of bamboo, especially ‘running’ bamboos, can be invasive due to their extensive root systems, which allow them to spread rapidly. However, not all species are invasive, and with proper management, the environmental impact can be minimized.

Organizer Bamboo Nursery

 

I've just bought some bamboo socks.

[Silebyfox_89]

36 minutes ago, davieG said:

Some facts about bamboo:

1.Fast Growth: Bamboo is the fastest-growing plant in the world. It has been recorded at growing 47.6 inches in 24 hours. Some species can even grow over a meter per day under optimal conditions. A new bamboo shoot reaches its full height in less than a year.

2. Oxygen Release: A grove of bamboo releases 35% more oxygen than any other tree out there.

3. Carbon Dioxide Absorption: Bamboo absorbs carbon dioxide at a rate of 17 tons per hectare every year. It can act as a valuable carbon sink given how fast the plant grows.

4. No Fertilizer Required: Bamboo doesn’t need fertilizer to grow. It can self-mulch by dropping its leaves and use the nutrients to grow.

5. Drought Resistance: Bamboos are drought-tolerant plants. They can grow in the desert.

6. Wood Replacement: Bamboos can be harvested in 3-5 years compared to the 20-30 years of most softwood trees.

7. Building Material: Bamboo is incredibly strong and sturdy. It has been used as support for concrete as well as scaffolding, bridges, and houses.

8. Soil Stability: Bamboo has a wide network of underground roots and rhizomes that prevent soil erosion.

9. Natural Air Conditioner: Bamboo cools the air surrounding it by up to 8 degrees in the summer.

10. Invasiveness: Some species of bamboo, especially ‘running’ bamboos, can be invasive due to their extensive root systems, which allow them to spread rapidly. However, not all species are invasive, and with proper management, the environmental impact can be minimized.

Organizer Bamboo Nursery

 

I've just bought some bamboo socks.

Originally brought to the UK by Cockney Dick van Dyke

[Zear0]

Fingers crossed Falcon 9 Bandwagon-3 goes up later as I'll be sat in the car by the side of the road watching it! Last two times I've been here I've missed out on any launches at all so third time lucky! 

[Zear0]

So cool! 

[blabyboy]

8 hours ago, Zear0 said:

So cool! 

Any pics?

[Zear0]

3 hours ago, blabyboy said:

Any pics?

Yeah, camera phone at night so fairly shite quality, but caught the main bits. 

 

First was the launch with the coolest bit being the sonic boom that rattled the buildings. 

 

 

Second pic was the first stage coming in to land with the second stage still visible in the sky. 

 

 

It was great to see when the second stage hits an altitude when the exhaust starts reflecting sunlight as it just instantly glows blue and looks amazing. Thank god for a good launch and a clear night. It was the second launch that day, so chances of seeing them go up are getting higher. Bar I was at had a few locals who didn't even turn around for it, see them all the time. 

 

https://www.spacex.com/launches/mission/?missionId=bandwagon-3

 

Edited 22 April by Zear0

[Dahnsouff]

Didn't we have a Nature thread? Maybe this belongs there

 

 

 

This I found interesting, especially when linked to the re-emergence of Beavers and escalating climate change

(Flood plains please...)

 

[leicsmac]

https://interestingengineering.com/science/all-you-need-to-know-about-the-sixth-mass-extinction-event

 

    Most conservation biologists today think humanity has already entered the sixth mass extinction phase due to the acceleration of species extinction.
    The sixth mass extinction will be the first to result from human (anthropogenic) actions, including human-induced climate change.
    Neanderthals, Denisovans, and Homo erectus all vanished. Homo sapiens could be next, but when?

Animals and plants go extinct all the time; it’s a part of how Earth works. We know this because over the last 500 million years or so, since the origin of multicellular life, there have been at least five major extinction events. Each of these wiped out between 75 and 90 percent of the world’s species at the time over a ‘short’ period of around 2.8 million years or less, and were brought on by dramatic but natural occurrences.

 

Animals and plants go extinct all the time; it’s a part of how Earth works. We know this because over the last 500 million years or so, since the origin of multicellular life, there have been at least five major extinction events. Each of these wiped out between 75 and 90 percent of the world’s species at the time over a ‘short’ period of around 2.8 million years or less, and were brought on by dramatic but natural occurrences.

 

A primer on the world as it is... and what our species is doing to it.