Hubble Shoots Movies of Stellar Jets 30
With his first accepted submission, aglider writes "A number of different science publications are reporting on a recent announcement made by NASA and Hubblesite.org. Quoting: 'A team of scientists [headed by Rice astronomer Patrick Hartigan] has collected enough high-resolution Hubble Space Telescope images over a 14-year period to stitch together time-lapse movies of powerful jets ejected from three young stars. The jets, a byproduct of gas accretion around newly forming stars, shoot off at supersonic speeds in opposite directions through space.' The report is also accompanied by a number of photos and, of course, astounding small movies. The complete scientific study, which dates back to 2011.07.20, has been published in the Astrophysical Journal (subscription needed) but is also available on the ESA's Space Telescope site (PDF)."
Re:Is that a jet or a tail? (Score:3, Informative)
The tail of a comet is caused by the star around which it orbits heating it up and blowing off the dust into a 'tail' shape. The tail does not trail behind the comet as it moves, but points away from the star it is orbiting.
Re:SuperSONIC speeds... (Score:4, Informative)
speed of sound (in the interstellar medium) is about 100 km/s
(source [wikipedia.org])
Yes, really.
Moron.
Re:Is that a jet or a tail? (Score:3, Informative)
From one of the videos it looks like a tail caused by the star moving... Could there be star-sized comets in the universe?
It depends on what you want to call a comet. The "dirty snow balls" at the nucleus of all the comet pictures you'd normally see are no bigger than an asteroid. When activated by solar energy, they develop a coma of gaseous material that is several times larger than the nucleus, but still pretty small. If you count the tail that streams away from the star, then yes: it is possible to say a particularly large and active comet can conceivably approach the diameter of a star. However, even as such, no comets are observable with today's technology at stellar distances of the order those Hubble observations are made.
if you'd left off the 'moron' (Score:3, Informative)
i would have modded you up
Re:Insects, we (Score:4, Informative)
No, we're not at all like insects. Insects are "cold-blooded", have chitinous exoskeleton and six legs, often wings and webbed eyes. We're very different. There's been like 600+ million years of evolution since our last common ancestor.
Sheesh, don't they teach biology in schools any more?