Blowing Bubbles in Space: The Birth and Death of Practically

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Transcript Blowing Bubbles in Space: The Birth and Death of Practically

Blowing Bubbles in Space: The
Birth and Death of Practically
Everything (Astronomical)
Heather Preston
TNS 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?
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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
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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
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•
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.
• 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]
Pne: Not really spherical
Helix nebula ctd
• Subaru observed one
small area and found
thousands of knots
(bow shocks)
• 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
PGC 3074547:
Boomerang Nebula
When we talk about binaries…
• Many
different
kinds of
masstransfer
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 lowmass 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
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
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/UMa
ss Amherst/M.D.
Stage et al.
• Scale 420”
• D 3067 pc
SN 1006
• D= 7200
ly
• Note
mass
concent
ration in
band!
• Type Ia:
was a
CV
• 60 lightyears
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.
•
•
•
•
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
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 (18Jun-2004) Australia
Telescope Compact Array
•
•
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)
Galaxies Blow Bubbles, too:
Centaurus A (2.5 Mpc)
• 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
Cygnus-A in radio
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/N
SF
M87: The model
• Artists's
Conception
of M87's
inner core:
Black hole,
accretion
disk, and
inner jets.
• CREDIT: Bill
Saxton,
NRAO/AUI/
NSF
• For scale.
Much to do…
• Consider computational fluid dynamics! 
• [email protected]