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BD5TB8 Alien and Older People, Cowes, Isle of Wight, England, UK, GB.

Could alien life forms live for hundreds or thousands of years?

There is no need to look further than Earth to find plants and animals that live extremely long lives, says one reader

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H3NTB2 Woman by giant trees in snow-covered forest, Sequoia National Park, California, USA

Why don鈥檛 trees rot in the ground, while wooden structures do? Part 2

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Last Word

What is this shape with three axes of symmetry called? Part 2

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PE5P96 Close up of two purple socks with yellow lemon detail, pegged to a washing line with two yellow clothes pegs, shot from below against a clear blue sky

This week鈥檚 new questions

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The events surrounding the Big Bang were so cataclysmic that they left an indelible imprint on the fabric of the cosmos. We can detect these scars today by observing the oldest light in the Universe. As it was created nearly 14 billion years ago, this light ???????? which exists now as weak microwave radiation and is thus named the cosmic microwave background (CMB) ???????? has now expanded to permeate the entire cosmos, filling it with detectable photons. The CMB can be used to probe the cosmos via something known as the Sunyaev-Zel????????dovich (SZ) effect, which was first observed over 30 years ago. We detect the CMB here on Earth when its constituent microwave photons travel to us through space. On their journey to us, they can pass through galaxy clusters that contain high-energy electrons. These electrons give the photons a tiny boost of energy. Detecting these boosted photons through our telescopes is challenging but important ???????? they can help astronomers to understand some of the fundamental properties of the Universe, such as the location and distribution of dense galaxy clusters. The NASA/ESA Hubble Space Telescope observed one of most massive known galaxy clusters, RX J1347.5????????1145, seen in this Picture of the Week, as part of the Cluster Lensing And Supernova survey with Hubble (CLASH). This observation of the cluster, 5 billion light-years from Earth, helped the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to study the cosmic microwave background using the thermal Sunyaev-Zel????????dovich effect. The observations made with ALMA are visible as the blue-purple hues. Links ESO Picture of the Week RX J1347.5????????1145 seen by Hubble only

We know how matter took shape, but how was space formed?

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Mass Product of Beer Bottles, Rows of glass production alcohol on industrial conveyor belt, top view.; Shutterstock ID 2416496749; purchase_order: -; job: -; client: -; other: -

Is the volume of gas at top of a beer bottle the same for all beers?

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P2H56B Weasel standing upright, Mustela nivalis, Germany

This week鈥檚 new questions

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Close-up of construction bubble level.

What does the angle of a spirit level mean relative to Earth?

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Coronal mass ejection 05/11/2018 3372 views 12 likes 402495 ID Like Download COOKIES To enable the sharing functionality, please accept all cookies. To adjust your cookie settings, click here. Details Related This image, acquired by the LASCO C2 coronagraph instrument on the ESA-NASA SOHO spacecraft, was taken 8 January 2002 and shows a widely spreading coronal mass ejection (CME) as it blasts more than a billion tons of matter out into space at millions of kilometers per hour. This C2 image was turned 90 degrees so that the blast seems to be pointing down. A second image, from the EIT disk imager on a different day was enlarged and superimposed on the C2 image so that it filled the occulting disk for effect. CREDIT ESA/NASA/Soho

Would a powerful solar storm knock out electronics in planes?

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2FWP497 Liquid iron molten metal pouring from ladle container into mold, industrial metallurgical factory, foundry cast, heavy industry background.

Is it possible to have a high-tech society without iron? Part 2

A reader points out that other metals can stand in for iron in most circumstances. With enough nickel and cobalt, you may even be able to get around the problem of harnessing magnetism

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This week鈥檚 new questions

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Does life require Earth鈥檚 rate of rotation to lie in a certain range?

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Should we genetically modify humans we send to Mars? Part 2

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This week鈥檚 new questions

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