Some stars know how one can make an exit. Right here’s the most recent picture from the James Webb Space Telescope, launched on April 7, 2023. It reveals what’s known as a supernova remnant – an enormous increasing cloud of particles in space – which earthly astronomers name Cassiopeia A, or Cas A. This cloudy shroud is what stays of an enormous star that exploded, from Earth’s perspective, some 340 years in the past. In fact, for any Cassiopeians residing close to this star, which is 11,000 light-years from Earth, the occasion occurred greater than 11,000 years in the past. Whereas the supernova ought to have been shiny sufficient for earthlings to see as a “new” star within the night time sky within the 1690s, nobody has but discovered a report of anybody’s having witnessed it.
Situated within the course of the constellation Cassiopeia, Cas A is the brightest radio supply in our sky, other than our sun. Webb imaged the supernova remnant within the infrared, which is between seen and radio on the electromagnetic spectrum.
At 340 years outdated, Cas A is the 2nd-youngest supernova remnant we all know in our Milky Way galaxy. The youngest is G1.9+0.3 – solely 150 years outdated – situated within the course of the constellation Sagittarius.
Supernovas are key to life. When a star explodes, it releases the heavy components made in its inside – together with the constructing blocks of life, corresponding to carbon, calcium and iron – into space. Components corresponding to these seeded life on Earth. And so they have the potential to seed life on distant worlds, too.
Supernova remnant in infrared
Within the picture above, the brilliant orange areas present the place materials ejected from the explosion is smashing into interstellar fuel and dust. The lighter, pinkish and considerably round area towards the inside are the stays of the star itself. These clumps and knots are a mixture of heavy components, together with oxygen, argon and neon. The greenish loop is one area that scientists are nonetheless attempting to grasp.
One of many questions scientists try to reply is … the place does cosmic dust come from? Even younger galaxies within the early universe include huge quantities of dust. Whereas supernovas seem more likely to be the reply, it doesn’t fairly clarify the quantity of dust. As ESA said:
By finding out Cas A with Webb, astronomers hope to achieve a greater understanding of its dust content material, which might help inform our understanding of the place the constructing blocks of planets and ourselves are created.
Backside line: On April 7, 2023, ESA shared this new picture from the James Webb House Telescope of supernova remnant Cassiopeia A. Be taught extra about it right here.
