• Question: when will the world end

    Asked by DAN to Colin, John, Kevin, Shikha, Triona on 17 Nov 2014. This question was also asked by 328bera39, 358bera49, clodagh :), Rebecca, sinead18, jamie, 624bera32, hsarah, Jomantas.
    • Photo: Tríona O'Connell

      Tríona O'Connell answered on 17 Nov 2014:

      when will civilisation collapse? Possibly in the next 100 years if we don’t get a handle on antibiotic resistance and global warming and find sustainable energy sources.
      When will the Earth be destroyed? Maybe in a few billion years when the sun gives up burning hydrogen and goes nova (or maybe it won’t be destroyed, it’ll just be a cold lump of rock going around in circles). I don’t think Humans will have the power to destroy the lump of rock we live on.
      When will the universe end? Who knows, it might go expanding forever, never ending but getting colder and more boring and spread out.

    • Photo: Colin Johnston

      Colin Johnston answered on 17 Nov 2014:

      Just adding to what Triona has already said…

      Our Sun now is a main sequence star. This means the Sun is in its prime of life, steadily converting hydrogen into helium in its core and producing heat and light as a by-product. There are huge stars called red giants. These are stars which are running out of hydrogen in their cores and are instead generating energy using other fuels such as helium. Producing energy this way makes them swell enormously into bloated stars with reddish surfaces, cool by stellar standards.

      In the distant future, 6.4 billion years or so from now our Sun is doomed to become one of these red giants. The Sun will redden, it’s surface cooling, and it will expand enormously. Planet Mercury will be absorbed by the expanding Sun, Venus will probably meet the same fate and the icy moons of Jupiter will be vaporised. But theory suggests Earth as a planet will survive but as an airless ball of rock.

      Red giant stars like the Sun will become blast off great clouds of gas until eventually all the star’s outer layers have been blown away into space. Eventually only the tiny shrunken core, about the size of the Earth, remains as what is called a white dwarf. White dwarf stars no longer produce light by nuclear fusion, merely continuing to glow like dying embers until they have slowly cooled to cold black balls of dense matter not much bigger than a planet.

      This will be the ultimate fate of our Sun. A cold, dead earth will still be orbiting it.

      Thankfully this sad fate lies far in the future!

    • Photo: Shikha Sharma

      Shikha Sharma answered on 18 Nov 2014:

      Hi DAN, 328bera39, 358bera49, clodagh :), Rebecca, sinead18,

      That’s a really difficult question as there are so many factors which can lead to the end of world…natural calamity due to global warming or the favourite one of all astrologers that an asteroid could hit Earth….As per a report from National Geographic “Within about five billion years, the sun will exhaust its nuclear fuel and bloat into a “red giant” star that may even engulf our planet”. The first hints of the death of life on Earth, the study found, will come in 500 million years, when less-hardy species of plants begin to die off as global carbon dioxide levels drop.
      You can see the list of predictions in past, current and future on the link mentioned below,
      Its such a long list…. 😀