Every Planet Is a Comet to a Space Physicist: from Jupiter to Pluto HAO
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Fran Bagenal HAO Visiting University of Colorado Scientist 1987 - 1988 Every Planet is a Comet to a Space Physicist: From Jupiter to Pluto New Horizons! EARTH ! Side! Mission To Pluto !Juno Solar! Wind! Equatorial plane! Connected – Global circulation Polar view! to solar wind! driven by solar wind! – Coupled to the planet Closed magnetic – Large scale, quasi- field! static reconnection! Delamere & Bagenal 2010, 2013! – Io#=#primary# source# # –##Coupled#to# rota4ng#planet## Delamere & Bagenal The aurora is the signature 2010, 2013! of Jupiter’s attempt to spin up its magnetosphere –##Io#plasma# ejected#as# plasmoids# ?! # –##Boundary#layer# interac4on#via# small:scale# ?! intermi;ant# reconnec4on # SIDE VIEW Juno –##Minimal#solar# wind# Juno ionosphere# High-M coupling# A TOP VIEW solar wind EQUATORIAL # PLANE –##Viscous# boundary#layers# # High-β plasma TOP – Io plasma VIEW carried away ABOVE SHEATH Orbit insertion by solar wind# 4th July 2016 Juno Juno Juno passes directly through Juno passes directly through auroral field lines auroral field lines Measures particles precipitating Measures particles precipitatingIs Jupiter a into atmosphere creating aurora into atmosphere creating aurora colossal comet?? Plasma/radio waves reveal Plasma/radio waves reveal processes responsible for particle processes responsible for particle acceleration acceleration UV & IR images provides context UV & IR images provides context for in-situ observations for in-situ observations Juno’s orbit: perfect for exploring polar magnetosphere Juno’s orbit: perfect for exploring polar magnetosphere 2nd Kuiper Belt object discovered 1992 Pluto orbits the Sun every 248 years! Asteroid Belt 1000 km Ceres 1000 miles Bennu! Density ~ Temperature: Earth at same scale 2g/cc 40 K 1988 ! 50:50 -233 C Star Atmosphere: rock:ice - 388 F occulted P~3-50 microbar by Pluto ! T~50K N2, CH4, CO Charon Pluto How big is Pluto's escaping atmosphere? Pluto's#Orbit# At 33AU solar • Heated atmosphere escapes Pluto's weak gravity wind flux 1000 • ~km of ices lost in 4 billion years times less than at Earth 1989 Pluto Underground In 1989 we started planning a mission 1989 Geophys.Eyes Res. & Lett. Ears Pluto issue to Pluto 1991 Outer Planets Science Working Group Alice Rex UV Radio Lorri Hi-res Ralph PEPSSI IR Particles SWAP Solar Wind Student Dust Counter New Horizons - Student Dust Counter SIX OBJECTS Kerberos TO STUDY Styx Pluto Pluto Charon After 9 ½ years! The New Horizons team has lots of women! Hydra Charon- Earth Moving at Occultation 14:20:09 Pluto-Earth 33,000 Occultation 12:52:30 15:00 mph! 14:00 Sun 13:00 0.24° Charon-Sun Earth 12:00 Occultation Pluto-Sun 14:17:50 Occultation 12:51:28 11:00 Charon C/A 10 mins 12:04:00 Pluto C/A Nix New Horizons Trajectory 29,432 km 11:50:00 13,695 km 13.78 km/s ~30% of the team Finally Alice Bowman And we all go nuts! (Mission Operations Manager – MOM) announces the spacecraft is well and full of data! Breath-taking! Complex Ice World with Hammond & Barr 2014 a Heart! Water Ice Acting like Rock? Water Ice Acting like Rock? EARTH: Nunataq – rock sticking out of ice It's Glaciology! No Atmosphere for Charon! Pluto's weak gravity produces an extended atmosphere https://www.youtube.com/watch?v=q6XzpJKl8DU https://www.youtube.com/watch?v=q6XzpJKl8DU https://www.youtube.com/watch?v=q6XzpJKl8DU Orange, brown, Explains why Comet black materials Pluto is red/ P67 C-G accumulate on brown while the surface over Charon Pluto billions of years remains grey Tholins: Complex Hydrocarbons https://www.youtube.com/watch?v=q6XzpJKl8DU PLUTO JUST RIGHT! COMET! LOW GRAVITY! MARS! – Weak solar HIGH GRAVITY! field at 33 AU! ! Gravity controls – Highly atmospheric escape! kinetic interaction # What a New Horizons Mission Trajectory ride!! ???? If NASA approves extended mission Potential Second Target – spring 2019 New Horizons will fly by a second KBO Sample Kuiper Belt Objects Thousands of them and Varied .