JET PROPULSION
HERBIG-HAROJET
Here,weseea Herbig-Harojet,whichspurtsoutof some
newbornstars.Aftera starforms,thereis usuallya disk
of gasanddustleftaroundit.Complexinteractions
betweenthisdiskandthestar’smagneticfieldmeanthat
someof thegasendsupbeingthrownoutat incredibly
highspeeds.Theshockwaveof thegasrippingthrough
theinterstellarmedium creates this brightly glowing
jet,asseenhere.
NotonlyhasHubble’shighprecisionbeenableto
revealthesejetsingreaterdetailthaneverbefore,we’ve
beenableto studythemastheygrow.Asthejetmoves
furtherout,it hitsnewknotsof gas,causingthemto
brightlyflareup,thenfadeawayovertimescalesof a few
years.Thishasgivenastronomersa unique view of the
usuallyinvisibleinterstellarmedium.
“Thirtyyearsis nota lotof timeintheastronomical
realm,”saysJenniferLotz,directorof theGemini
Observatory.“Butwenowhavemoviesthatshowejecta
frommassivestars.Thisopensupnewwaysto
understandthesephenomena,beyond just an
instantaneous snapshot of time.”