Victor Doroshenko

astrophysicist@IAAT

Sep 12, 2020

eROSITA finds large-scale bubbles in the halo of the Milky Way

Now finally out of the embargo! The detailed press-release is available at our webpage, but I must also briefly summarize it here: basically eRosita has just found gigantic "bubbles" encompassing famous Fermi Bubbles, so even larger than those! In eRosita all-sky survey they look like that

bubbles

Here the false-color map the extended emission at energies of 0.6-1.0 keV highlights the structure extending from teh Galactic center upwards and downwards. The upper part was actually already known in X-rays as a North Polar Spur (NPS), but it was believed to be a local structure associated with an old SNR or somethign similar. Now it became clear that NPS together with the newly seen part form structure analogous to Fermi bubbles, which we called eRosita bubbles. That thing is huge and required huge amount of energy to blow! The source of energy is still uncertain, so lots to be done in the near future.

cartoon

Schematic view of the eROSITA (yellow) and Fermi bubbles (purple). The galactic disk is indicated with its spiral arms and the location of the Solar System is marked. The eROSITA bubbles are considerably larger than the Fermi bubbles, indicating that these structures are comparable in size to the whole galaxy. As you could imagine, we went to Nature to publish this discovery.

From my side, I'd like to add that the latest touches to the images now published were prepared in August, just before we went off to vacations in Italy. Basically, I were running circles between the laptop and stuff scattered all around the house and partly in the car already! Now it has payed off, which I'm really happy about.

PS. Vacation was nice too!