3 ms·
The 1/3 missing baryons is composed of oxygen gas?! That is a huge change, right? I thought the elemental distribution of the universe is around 90% hydrogen,
by dwaltrip 8y ago
The 1/3 missing baryons is composed of oxygen gas?! That is a huge change, right?
I thought the elemental distribution of the universe is around 90% hydrogen, 8% helium, and 2% all the other elements (going off memory here).
- antognini 8y agoNo, while the observations were of oxygen, this doesn't imply that the gas is primarily made of oxygen. The issue with the warm-hot IGM is that it is a strange temperature where virtually nothing emits much light. Highly ionized oxygen (in this case, only one electron out of the original eight remain bound) is one of the few things that does. Here, based on X-ray observations they have estimated the density of this oxygen, and then estimated the overall density of the IGM based on the ratio of oxygen to hydrogen.
- wrycoder 8y agoThanks for that explanation. With it, the abstract makes sense regarding the fully ionized hydrogen. The phys.org article ("That lost matter exists as filaments of oxygen gas") does not.