https://padlet.com/53765/x680il6kwhha en-us 2018-03-05 15:24:39 UTC 2018-03-05 15:46:42 UTC hello@padlet.com 53765 https://padlet.com/53765/x680il6kwhha/wish/238134874 2018-03-05 15:27:38 UTC https://padlet.com/53765/x680il6kwhha/wish/238134874 53765 https://padlet.com/53765/x680il6kwhha/wish/238135653 Thor's Helmet is classified as an emission nebula]]> 2018-03-05 15:28:35 UTC https://padlet.com/53765/x680il6kwhha/wish/238135653 53765 https://padlet.com/53765/x680il6kwhha/wish/238136711 TH spans 30 light years across]]> 2018-03-05 15:30:07 UTC https://padlet.com/53765/x680il6kwhha/wish/238136711 53765 https://padlet.com/53765/x680il6kwhha/wish/238137563 It is located about 12,000 light years away from us]]> 2018-03-05 15:31:19 UTC https://padlet.com/53765/x680il6kwhha/wish/238137563 53765 https://padlet.com/53765/x680il6kwhha/wish/238137961 Located in the constellation Canis Major]]> 2018-03-05 15:31:57 UTC https://padlet.com/53765/x680il6kwhha/wish/238137961 53765 https://padlet.com/53765/x680il6kwhha/wish/238138714 Its central star is 280,000 times brighter than the sun]]> 2018-03-05 15:32:58 UTC https://padlet.com/53765/x680il6kwhha/wish/238138714 53765 https://padlet.com/53765/x680il6kwhha/wish/238139777 The central star is believed to be 20 million years old]]> 2018-03-05 15:34:24 UTC https://padlet.com/53765/x680il6kwhha/wish/238139777 53765 https://padlet.com/53765/x680il6kwhha/wish/238140631 TH is the result of its central star expelling its outer layers]]> 2018-03-05 15:35:32 UTC https://padlet.com/53765/x680il6kwhha/wish/238140631 53765 https://padlet.com/53765/x680il6kwhha/wish/238141213 The overall helmet shape is a result of interaction of the expanding bubble of expelled material with giant molecular clouds in the area]]> 2018-03-05 15:36:20 UTC https://padlet.com/53765/x680il6kwhha/wish/238141213 53765 https://padlet.com/53765/x680il6kwhha/wish/238141919 Different parts of Thor’s Helmet are expanding at different rates, estimated to be from 10 km/s to 30 km/s or more. The different rates of expansion put the estimates of the nebula’s age in the range between 78,500 and 236,000 years]]> 2018-03-05 15:37:19 UTC https://padlet.com/53765/x680il6kwhha/wish/238141919 53765 https://padlet.com/53765/x680il6kwhha/wish/238142433 The ionizing radiation of the central star is responsible for the nebula's glow]]> 2018-03-05 15:38:01 UTC https://padlet.com/53765/x680il6kwhha/wish/238142433 53765 https://padlet.com/53765/x680il6kwhha/wish/238147813 2018-03-05 15:44:57 UTC https://padlet.com/53765/x680il6kwhha/wish/238147813