Blowing Bubbles in Space: The Birth and Death of Practically
Everything (Astronomical)
Heather PrestonTNS First Global General Gathering
It’s a Gas…• 90% of the atoms in the Universe (by number of
atoms) are Hydrogen atoms (~73% by mass). • More than 9% of what’s left is Helium atoms
(~25% by mass).• Crystalline solids and anything heavier than
Beryllium are the result of the life cycles of stars (usu. s-process and r-process nucleosynthesis)
• The Iron in your blood came from an exploding star
• Reference: 1 AU = 150 Mkm = 93 Mmi• 1 ly = 9.46 trillion km• 1 pc = 3.26 ly
Bang the gases together, guys…
• The study of how gases of different speeds, compositions, densities and/or temperatures interact is therefore the study of just about every phenomenon in astrophysics at some time or another (they do other things too!)
• Shorthand: “Blowing Bubbles”
What Phenomena Blow Bubbles?
• Stars, as they begin to coalesce• Stars, when they drive stellar winds • Stars, in binary systems• Stars, at the ends of their lives• “Planetary” nebulae• Supernovae• Galaxies with active nuclei
Stars and abbreviations
• This is the Hertzsprung-Russell diagram, with some famous sample stars on it. Notice MS and RGB plus wdw…
The Quick, the Slow, and the Dead• All stars go through a protostar phase. It’s a
short phase relative to the star’s total lifetime. That makes it harder to observe.
• All stars go through a longer-lived MS phase• All stars above 0.3 M go through a red giant
phase: RG life < MS life• All stars die. The more massive ones complete
every phase faster, and are a LOT brighter. • Death throes include (low-M to hi-M):
PN→WD or SN→NS or SN→BH
Creating Something out of Gas• Things fall together (gravity never sleeps)• The center cannot cool (ideal gas law)• Angular momentum is hard to get rid of• Hence, the pancake is the official food of the
astronomical universe… we see disks, and gas outflows, in:
• Star formation– Planetary system formation
• Binary systems (incl M binaries)• Star death events like PN and SN• Galaxies
A Star is Born: Protostars, YSOs & Herbig-Haro objects
• Or sometimes, several things are happening at once… a dust-shrouded (150m) binary protostar…
• MERLIN 5GHz radio shows bipolar outflow
• HST WFPC: hot bubble inflated
• SUBARU shows a bow shock between YSO system and ambient ISM
• protostellar jet L1551 IRS5 in Taurus D=450 ly
L1551 IRS 5
Star Forming Region S106• Credit : CISCO, Subaru
8.3-m Telescope, NAOJ• Massive star IRS4 Cygnus• Age:100,000 years • Neb: Sharpless 106
Nebula (S106) D=2kly• A large disk of dust and
gas orbiting Infrared Source 4 (IRS4), visible in dark red near the image center, gives the nebula an hourglass shape.
• Detailed inspection of this representative color infrared image has revealed hundreds of low-mass brown dwarf stars lurking in the nebula's gas. S106 spans about 2 light-years
HH 212: more jets from a protostar
• Sometimes the jets are so well collimated that they resemble much higher-energy features. This one goes right down to within 500 AU of the protostar!
• Credit: IRAM Codella ++ 2003 A Ap 462L53
Planetary Nebulae
• Planetary nebulae are the final stages in the lives of low-mass stars, such as our Sun. As they reach the ends of their lives, their late RGB superwinds send off large amounts of material into space. Although the nebulae can look like a fireworks display, the process of developing a nebula is (usually!) neither explosive nor instantaneous; it takes place over a period of about 10,000 to 1,000,000 years. This gradual process creates these nebulae by exposing their inner cores, where nuclear burning once took place and from which bright ultraviolet radiation illuminates the ejected material.
Pne: Not really spherical• Helix
Nebula NGC 7293 The white box shows the area observed by the Subaru Telescope. Credit: NASA, NOAO, ESA
• M. Meixner [STScI], and T.A. Rector [NRAO]
Helix nebula ctd
• Subaru observed one small area and found thousands of knots (bow shocks)
PGC 3074547: Boomerang Nebula• AKA Centaurus
bipolar nebula• D=5 kly• Pre-PN• Vout=600,000 kph• Shining with light
from the central star reflected by dust, the frigid Boomerang Nebula is believed to be a star or stellar system evolving toward the planetary nebula phase
When we talk about binaries…• Many
different kinds of mass-transfer binaries. This is the recurrent nova RS Oph as rendered by space artist David A. Hardy (STFC, UK)
Lagrange Equipotentials
• Outer Lagrange point losses take place in a system where mass arrives at L2 or L3 with some momentum
Peeking into the deathbed of a low-mass star: the pPN M1-92
• Top: map of the total integrated IR emission with IRAM, while the inset shows the continuum HST image at 547 nm and the same size scale.
• Bottom: position vs. velocity diagram for a cut along the symmetry axis of the nebula. The vertical bar=5000 AU (upper R of imaged nebula at top is an expanding ellipsoidal shell tilted TOWARD the viewer, and there is rotating material near the “equator” of the nebula)
Pneb: MyCn 18
• MYCn 18 (8000 ly dist) credits: NASA, R. Sahai, J. Trauger (JPL), and The WFPC2 Science Team
Gas Dynamic Simulations
Gas Dynamic Simulations
Icke’s simulation of MyCn18: Note the extra bubbles at the tips of the lobes. Icke has also applied this model to Mz3:“The smaller bubbles protruding from the shock were not understood until recently; these remarkable features are due to an inward deflection of the highly supersonic gas that bounces off the inner walls of the nebula, causing a double vortex that moves outward with great violence. “
Eta Carinae• Eta Carinae
suffered a giant outburst about 160 years ago, when it became one of the brightest stars in the southern sky. Though the star released as much visible light as a supernova explosion, it survived the outburst.
Eta Carinae: inside scoop• Eta Carinae was observed by Hubble in September 1995
with the Wide Field Planetary Camera 2 (WFPC2). Images taken through red and near-ultraviolet filters were subsequently combined to produce the color image shown. A sequence of eight exposures was necessary to cover the object's huge dynamic range: the outer ejecta blobs are 100,000 times fainter than the brilliant central star.
• Observer: Jon Morse (University of Colorado), and NASA• It’s actually a binary system (P 5.52 y) with the most
massive component < 100 Msol LBV (4 – 8 mag) 7500 ly=D
There are still Mysteries: He2-47
WFPC2. R. Sahai JPL/STScI 2000
Bigger Bubbles: Supernovae• This very deep
Chandra image shows Cas A, the youngest supernova remnant in the Milky Way
• Age: 330 y• Image credit:
NASA/CXC/UMass Amherst/M.D. Stage et al.
• Scale 420”• D 3067 pc
SN 1006• D= 7200
ly• Note
mass concentration in band!
• Type Ia: was a CV
• 60 light-years across
SN E0102-72• An analysis of all the data
indicates that the overall shape of E0102 is most likely a cylinder that is viewed end-on rather than a spherical bubble.
• The intriguing result implies that the massive star's explosion has produced a shape similar to what is seen in some planetary nebulae associated with lower mass stars.
• SMC=190 kly away, so this field of view spans about 150 light-years.
SN LMC N 63A• D=160 kly• M=50Msol
• In SFR N63• Age 2000
to 5000 y• But wait,
there’s more!
• Credit: You-Hua Chu STScI
SN LMC N 63A extended mix• Extended Diam = 60 ly• The x-ray emission (blue),
is from gas heated to 10 million degrees C as knots of fast moving material from the cosmic blast sweep up surrounding interstellar matter. Radio (red) and optical emission (green)
• X-ray: J. Warren (Rutgers) et al., CXC, NASA Optical: Y.Chu (U. Illinois), STScI, NASA Radio: J.Dickel (U. Illinois) et al. and
• Composite: Bob Sault (18-Jun-2004) Australia Telescope Compact Array
Galaxies Blow Bubbles, too:Centaurus A (2.5 Mpc)
• The 870-micron submm data, from LABOCA on APEX, are shown in orange. X-ray data from the Chandra X-ray Observatory are shown in blue. Visible light data from the Wide Field Imager (WFI) on the MPG/ESO 2.2 m telescope located at La Silla, Chile, show the background stars and the galaxy’s characteristic dust lane in close to "true color".
• Credit: ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray)
Cygnus-A in radio• Cygnus A
just looks like a few little blobs in optical. At 600 million ly, who wouldn’t?!
• Jets are about 391,00 ly in extent at the distance typically associated with the galaxy (cD)
• Double Radio src AGN
Galaxy M87
• D= 60 Mly• Dominates the
Virgo Cluster• Vis vs radio!
Large-scale VLA image of M87: White circle indicates the area within which the gamma-ray telescopes could tell the very energetic gamma rays were being emitted. To narrow down the location further required the VLBA. CREDIT: NRAO/AUI/NSF
Radio structure is~ 200 kly across
M87
• Zooming in on the powerful core of the galaxy M87
• CREDIT: Bill Saxton NRAO/AUI/NSF
M87: The model
• Artists's Conception of M87's inner core: Black hole, accretion disk, and inner jets.
• CREDIT: Bill Saxton, NRAO/AUI/NSF
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