Heat and pressure

Metamorphism is the part of the rock cycle where rocks change into different rocks when subjected to heat and pressure, which can come from a variety of sources. Examples might include a granite intruding into other rocks, heating them and altering them as element charged fluids are spat out during the slow cooling process (called contact metamorphism, usually resulting in aureoles of different sets of characteristic minerals around the intruding pluton), or the huge pressures generated during continental collision, when large slabs of rocks called nappes detach from the lower crust and pile up in slow motion like a pushed tablecloth. The rocks at the bottom of the heap (now called a mountain chain) are baked and crushed until the minerals start to change.

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Zooming into VISTA’s view of Messier 78

This zoom sequence opens with a wide-field view of the Milky Way. We close in on the constellation of Orion and, as we zoom in on to a region close to Orion’s famous belt, a fascinating region of dust and reflection nebulosity starts to come into view. The final scene reveals a colourful and richly detailed new image of Messier 78 taken with the VISTA infrared survey telescope at ESO’s Paranal Observatory in Chile.

ESO/S. Brunier/Chris Johnson, ( Music: Mylonite Recordz Production