Starship Asterisk*

HEAPOW: Jet Speed (2018 Aug 06)

Enormous jets of particles and radiation often seen emanating from external galaxies point to a deep dark astrophysical secret: the presence of a supermassive, actively feeding black hole lurking near the galactic center. Such supermassive black holes contain the mass equivalent of millions, or billions, of suns packed into a space no larger in radius than the orbit of Uranus. It's almost unbelievable to think that these tiny regions produce powerful partcle beams, sometimes driven for hundreds of thousand of light-years deep into intergalactic space. All this energy is believed to be the result of the accretion of galactic material by the black hole. How the black hole converts the ingest of matter to a strong, narrow outflowing particle beam is still not fully understood. Apparent mysteries abound, like the jets that seem to speed through space at velocities faster than light (understood now as some weird relativistic optical illusion). The radio galaxy 3C31 (NGC 383) shows a spectacular example of a kinky radio jet speeding away from the black hole at the center of the galaxy, and evidently changing velocity and direction as it hits material lying outside the galaxy. The image above shows an optical image of NGC 383, with a Chandra X-ray Telescope image (in blue) superimposed. The X-ray image shows energetic emission from the body of the galaxy itself, and clearly shows a jet-like structure of X-rays extending towards the top of the image. The X-ray emission from with this part of the jet provide unique clues about the nature of the jet at this critical juncture, where it appears to be changing most rapidly. This image was re-released as part of the Chandra Archives Collection in honor of American Archives Month.

Ann wrote: ↑Tue Aug 07, 2018 5:19 am
The optical image used for the composite optical/X-ray image of NGC 838 is a Hubble Legacy Archive image processed by Geck.

Do read Geck's comment on the Wikipedia page, where she notes that the number 838 is a palindromic prime number.

Chris Peterson wrote: ↑Tue Aug 07, 2018 5:40 am

Ann wrote: ↑Tue Aug 07, 2018 5:19 am
The optical image used for the composite optical/X-ray image of NGC 838 is a Hubble Legacy Archive image processed by Geck.

Do read Geck's comment on the Wikipedia page, where she notes that the number 838 is a palindromic prime number.

383. 838 is obviously not prime (even if it is palindomic)!

Chris Peterson wrote: ↑Tue Aug 07, 2018 5:40 am

Ann wrote: ↑Tue Aug 07, 2018 5:19 am
The optical image used for the composite optical/X-ray image of NGC 838 is a Hubble Legacy Archive image processed by Geck.

Do read Geck's comment on the Wikipedia page, where she notes that the number 838 is a palindromic prime number.

383.

838 is obviously not prime (even if it is palindomic [sic])!

https://www.etymonline.com/word/palindrome wrote:
palindrome (n.) "line that reads the same backward and forward," 1620s, from Greek palindromos "a recurrence," literally "a running back." Second element is dromos "a running" (see dromedary); first is palin "again, back."

dromedary (n.) late 13c., from Old French dromedaire, from Late Latin dromedarius "kind of camel," from Latin dromas (genitive dromados), from Greek dromas kamelos "running camel," from dromos "a race course," from dramein "to run." A variety of the one-humped Arabian camel bred and trained for use as a saddle-animal, "and comparing with the heavier and slower varieties as a race-horse does with a cart-horse."

dome (n.) "round, vaulted roof," 1650s, from French dome (16c.), from Provençal doma, from Greek doma "house, housetop", related to domos "house." In the Middle Ages, German dom and Italian duomo were used for "cathedral" (on the notion of "God's house"), so English began to use this word in the sense "cupola," an architectural feature characteristic of Italian cathedrals.