ASTR 2020
Space Astronomy
Week 9:
Dark energy
Visual/near-IR space astronomy:
-Balloons, Copernicus, HST, Kepler,
JWST, HDST,…..
- IR astronomy: the “cold Universe”
IRAS, ISO, Spitzer, Herschel, Planck
Announcements:
- Midterm #1 : Monday 14 March
Three “cornerstones” of
Modern Cosmology:
•
Expansion of the Universe (Hubble)
V=HD
•
H ~ 71+/- 3 km/s Mpc-1
Abundances of the elements
H, He => “Big Bang”
all else came from => “stars”
•
Cosmic Microwave Background
Universe was smooth to 2 parts 105
13.7 Gyr ago, ~ 400,000 years after the Big Bang
Goals of Visual, near-UV, near-IR
Space Astronomy:
•
Get above atmospheric turbulence: Better than 1” !
Lyman Spitzer’s vision (late 1950s … a large space
telescope)
0.35 m <  < 2.4 m
•
Probe Universe without atmospheric obscuration:
 < 0.35 m (3,500 Angstroms)
UV absorbed by electronic transitions …
 > 2.4 m (3,500 Angstroms)
water, CO2, OH airglow, black-body radiation
ASTR 2020
Space Astronomy
Week 9:
Dark energy
Visual/near-IR space astronomy:
-Balloons, Copernicus, HST, Kepler,
JWST, HDST,…..
- IR astronomy: the “cold Universe”
IRAS, ISO, Spitzer, Herschel, Planck
Announcements:
- Midterm #1 : Monday 14 March
Major Visual, near-UV missions:
•
Project stratoscope (36” on a balloon at 100,000 feet)
•
Copernicus UV satellite (1972 - 1981) spectra
•
International Ultraviolet Observatory
(IUE; 1978 - 1996) spectra
•
Hubble Space Telescope (HST; 1990 - present )
•
Far Ultraviolet Spectroscopic Explorer (FUV spectra)
(FUSE; 1999 - 2007)
•
Galaxy Evolution Explorer (UV imaging)
(GALEX; 2003 - 2013)
•
•
Hipparcos (1989 - 1993) Astrometry
GAIA (2013 - present) Astrometry
Hubble Space Telescope
HH 46/47
HH 46/47
NTT
[OII] Ha [SII] m
HH 46/47
HH 46/47 Spitzer
(Noriega-Crespo 04)
H2 PAH 3.6, 4.5, 8 m
HH 46/47
2.6 mm CO J=1-0
contours
Arce et al. 2013
HH 46/47
(Hartigan et al. 05, AJ)
Balmer filaments
HST 1994
HH 46/47
(Hartigan et al. 05, AJ)
Balmer filaments
HST 1997
NGC 2024
Horsehead
Nebula
 Orionis
(OB 1 c)
NGC 1981
(OB 1 c)
(OB 1 d)
NGC 1977
Orion
Nebula
 Ori
NGC1980
Source of  Col + AE Aur
Disks & planet formation:
Smith, Bally, Licht, Walawender 05
d253-535 in M43
Young Proto-planetary Disk
Orion B
NGC 2068
LkHa 212/213
LkHa 312/ 313
HH 24 Ha [SII]
B. Reipurth / Subaru
N-Body dynamics: > 6 YSOs + jets
HH 24
Ha
[SII]
B. Reipurth
Subaru
Wide-Field Infra-Red Survey Telescope (WFIRST)
2.4 meter primary (surplus from DOD)
James Webb Space Telescope
6.5 - meter diameter
Earth-Sun L2 (~106 km from Earth): 2018
James Webb Space Telescope (model)
James Webb Space Telescope (model)
James Webb Space Telescope (deployment & orbit)
ASTR 2020
Space Astronomy
Week 9:
Dark energy
IRAS, ISO, Spitzer, Herschel, Planck
Announcements:
- Midterm #1 :
Monday 14 March
Exoplanets are DIM
Exoplanets are DIM
Finding another Earth: visual spectra
Finding another Earth: near-IR spectra
Starshade:
Exo-planets
Use with WFIRST ?
Future Telescopes:
WFIRST, 2.4 meter primary
James Webb Space Telescope, 6.5 m
High-Definition Space Telescope, 11.7m
High-Definition Space Telescope, 11.7m
Major Infrared missions:
Need for cryogenic cooling ! (Liquid Helium ….)
•
Infrared Astronomy Satellite (IRAS; 1983)
•
Infrared Space Observatory (ISO; 1995 - 1998)
•
Akari (Astro-F; 2006 - 2011)
•
Midcourse Space Experiment (MSX; 1996 - 1997)
•
Spitzer Space Telescope (Spitzer; 2003 - present)
•
Submillimeter Wave Astronomy Satellite
(SWAS; 1998 - 2005)
•
Wide-field Infrared Survey Explorer
(WISE; 2009 - 2013)
Herschel Space Observatory / Planck (2009 - 2013)
•
Herschel Space Observatory:
(May 2009 - April 2013)
D = 3.5 meter @ L2
PACS: 70, 100, 160 m
SPIRE: 250, 350, 500 m
HIFI:
THz heterodyne
Herschel Galactic Plane Survey
(Hi-GAL)
Our Milky Way @ visual wavelengths
Our Milky Way @ near infrared wavelengths
Our Milky Way @ far infrared wavelengths
Distant galaxies:
1 Billion years ago: distant galaxies @ near-IR wavelengths
Cosmic Microwave Background:
Snapshot of 3,000 K plasma when Universe was 300,000 yrs old
Redshifted by Expansion of the Universe x1,000 => 3 K
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
Sgr C
24 m
(Hinz 2008; Yusef-Zadeh 2009)
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
70 m
Sgr A
Sgr C
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
160 m
Sgr C
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
250 m
Sgr C
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
350 m
Sgr C
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
500 m
Sgr C
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
Sgr C
1100 m
(Bolocam Galactic Plane Survey
Ginsburg et al. 2012)
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
Sgr C
20 cm
(Yusef-Zadeh 2009)
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
Sgr A
Sgr C
24 m
(Hinz 2008; Yusef-Zadeh 2009)
Bania’s Clump 2
l = 1.3
Sgr B2 / B1
70 m
Sgr A
Sgr C
Central Molecular Zone
24 m, 70 m, 350 m
Central Molecular Zone
24 m, 70 m, 350 m
Central Molecular Zone
20 cm, 70 m, 350 m
Central Molecular Zone
20 cm, 70 m, 350 m
Central Molecular Zone
20 cm, 70 m, 350 m
24 m
350 m
2/3 gas, dust: @ Pos. longitudes
2/3 24 m sources: @ Neg. longitudes
1o => R ~ 150 pc, torbit ~ 8 Myr
Sgr B2
Inert, stable CMZ
Sgr A*
Starburst region
Sgr B2
Sgr B1
8 m 70 m 350 m
G0.25
GCB
50 km/s Sgr A 20 km/s
Central Molecular Zone
20 cm, 70 m, 350 m
Galactic Center: 20 cm
Sgr A (CNR)
N(H2) from dust
(Rome algorithm)
Sgr A (CNR)
Tdust cold ~ 14 K warm ~ 50 K
(Rome algorithm)
Sgr A (CNR)
Galactic Center: 8 m
Sgr B2
Sgr A (CNR)
Galactic Center Bubble: 24 m
Sgr A (CNR)
Sgr A (CNR)
8 m 70 m 350 m
Galactic Center: 20 cm
Sgr A (CNR)
Galactic Center Bubble => Sofue-Handa Lobe
=> Fermi-LAT Bubble ?
Finkbeiner et al. (2010)
SofueHanda
Lobe
3.5 cm
(GBT)
2 deg.
Law et al. (2009, 2010)
Caution:
Sco-Cen superbubble
150 pc from Sun
The Fate of the Visible Universe
 Hubble constant:
expansion rate
NOW
 DARK MATTER:
pulls expansion
curves down
 DARK ENERGY:
pushes expansion
curves up
Redshift:
z=
obs - em
em
Cosmic Microwave Background
SPACE missions
•
COsmic Background Explorer (COBE)
1989 - 1993
Differential Microwave Radiometer
Far-InfraRed Absolute Spectrophotometer
Diffuse InfraRed Background Experiment
•
Wilkinson Microwave Anisotropy Probe (WMAP)
2001 - 2010
•
Planck
2009 - 2013
Cosmic Microwave Background
(COsmic Background Explorer - COBE)
2.728 K Black Body
Remove constant
background (2.728 K):
Solar motion
at ~600 km/s toward
Virgo (Doppler shift)
Cosmic Microwave
Background (CMB)
Remove Solar motion
“CMB” + Galactic Plane dust
Remove model of
dust emission
=> True CMB
Cosmic Microwave Background
(Wilkinson Microwave Anisotropy Probe - WMAP)
Snapshot of the Universe when it was 380,000 yrs old
Then: 1/2 temperature of Sun’s surface:
(13.7 billion years ago!)
Today: 3 C above absolute 0!
Dark Energy
• Type Ia supernovae:
=> Explosions of 1.4 Solar mass
white dwarfs accreting from companion
=> `Standard candle!’
=> Dimmer (farther) then expected from
redshift
=> Expansion of Universe accelerating !
(since 5 – 10 Billion years ago)
• Cosmic Microwave Background:
=> `Standard Ruler’!
=> Geometry of Universe is flat
=> Requires more than ordinary matter (4%)
dark matter
(26%)
Dark energy: tension in the vacuum! (70%)
Matter dilutes; dark energy is constant as volume grows:
Black holes:
Escape speed = speed of light
R = 2 GM / c2 ~ 3 km/s x Mass(Solar masses)
Stellar mass black holes: M = 1 to 100 Mo
Remnants of core collapse supernovae
of stars with initial mass M > 30 Solar masses
Intermediate-mass black holes:
Centers of Globular clusters ?
Super-massive black holes:
In centers of Galaxies: 106 - 1010 Mo
Mini black holes?
Formed in Big Bang?
Minimum mass due to Hawking radiation
Active Galactic
Nuclei (AGN)
- Quasars
- Seyferts
- Radio galaxies
The History of our Universe