Exploring the Cosmos from the Moon

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Exploring the Cosmos from the Moon Jack Burns and
the NLSI LUNAR Team University of Colorado at
Boulder and NLSI
NLSI Science Forum July 22, 2009
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LUNAR Lunar University Network For Astrophysics
Research http//lunar.colorado.edu
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Key Project Gravitational Physics Lunar
Structure via Lunar Laser Ranging
Lead Scientists T. Murphy (UCSD), D. Currie (U.
Maryland), S. Merkowitz (GSFC)
Apollo 14 retroreflector at Fra Mauro
APOLLO Apache Point Observatory Lunar
Laser-ranging Operation
Bender, Alley, Currie, Faller, Dicke et al.

• Current Capabilities
• Accuracy 1 mm.
• Strong Equivalence principle ? lt 4 x 10-4.
• G/G lt6x10-13 per year.
• Deviation from inverse-square law is lt 3x10-11
  times strength of gravity at 108 m scales.

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Next-Generation Laser Retroreflector Array for
the Moon (see D. Currie talk today in Session
III-B)

• Fundamental Questions on Gravity
• Does Dark Energy exist?
• Is the Equivalence Principle exact?
• Do the Fundamental Constants of Nature vary with
  space and time?
• Do extra dimensions or other new physics alter
  the inverse square law?
• Opportunities for Probing Fundamental Gravity
  with Solar System Experiments, Science White
  Paper submitted to Astro2010.

Accuracy goal 10 µm
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Key Project Radio Heliophysics from the Moon
Lead Scientists J. Kasper (CfA) and R. MacDowall
(GSFC)
Type II Burst source location
Complex Type III source location

• How does cosmic ray acceleration occur within
  the heliosphere?
• A low frequency radio array will produce the
  first high angular
• resolution (1o at 10 MHz), high time
  resolution images of solar radio
• emissions (outer corona).

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ROLSS Radio Observatory for Lunar Science Sortie
see J. Kasper poster
A Pathfinder for a future long-wavelength farside
lunar array (10-100 sq. km). Operating at 1-10
MHz (30-300 m). Array consists of three 500-m
long arms forming a Y each arm has 16 antennas.

• Arms are thin polyimide
• film on which antennas
• transmission lines are
• deposited.
• Arms are stored as 25-cm
• diameter x 1-m wide rolls
• (0.025 mm thickness).

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Laboratory Testing at U. Colorado of Polyimide
Film as Low Frequency Antenna Backbone

• Experimental Set-up
• 12 24-hr duty cycles with T -150 C to 100 C.
• Exposed to UV with deuterium lamp during day
  cycle.
• Results
• No significant change in material or electrical
  characteristics during thermal cycling.

polyimide film installed on table in vacuum
chamber
J. Burns with Ted Schultz and Bobby Kane, CU CASA
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The Dark Ages Viewed via the Highly Redshifted
21-cm Line (see talks in Session III-B today by
Bowman, Furlanetto, Hewitt)
Loeb, A. 2006, Scientific American, 295, 46.
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Key Project Low-Frequency Cosmology
Astrophysics from the Moon
Lead Scientists J. Lazio (NRL), J. Hewitt (MIT),
C. Carilli (NRAO)
Time since the Big Bang (years)
Recombination
400,000
Z 1100
The Global (sky-averaged) HI Signal
Lunar Radio Array
Dark Ages
500 million
Z 10
Reionization
1 billion
Z 6
JWST, ALMA, MWA, LOFAR
9 billion
Z 0.5
Pritchard Loeb, 2008, Phys. Rev. D., 78, 3511.
21 (1z) cm 1420/(1z) MHz At z10, ? 2.3 m
(130 MHz) At z50, ? 10.7 m (30 MHz)
Today
13.7 billion
Z 0
10
Lunar Advantage No Interference
100 MHz z13
200 MHz z6
RAE-2 1973
Destination Moon!
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Roadmap to the Early Universe via Earth the Moon
Lunar Farside
Western Australia
Lunar Orbit
EDGES
MWA
PAPER
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Big Questions in Astrophysics Cosmology that
may be addressed with redshifted HI line at lt100
MHz

• Does the standard cosmology model describe the
  universe during the Dark Ages? Were there
  exotic heating mechanisms, such as Dark Matter
  decay, that occurred before the first stars
  formed?
• How does the intergalactic medium evolve during
  this important time, ending with reionization of
  hydrogen?
• What are the properties of high-z galaxies? How
  did they affect the Universe around them?
• What is the nature of the field that drove the
  Universe during Inflation?

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Key Project Assessment of Other Astrophysics
Enabled by a Return to the MoonLead Scientists
E. Hallman and J. Burns (Colorado)
8-meter monolithic telescope inside Ares V
20-meter liquid mirror telescope
See poster by E. Hallman
Lunar Cosmic Ray Detector
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Education and Public OutreachLead Scientist
Doug Duncan (Colorado)

• Planetarium Programs
• Back to the Moon, Back to the Future (adult,
  bilingual, science of/on/from the Moon).
• Max Goes to the Moon (childrens program).
• Formative evaluation assessment national
  distribution content drawn from all NLSI teams.
• Teacher Workshops
• Adapt develop curriculum focusing on lunar
  science.
• Hands-on classroom activities, including
  Galileoscope (IYA).
• Participate in Moon analog deployment activities
  for astrophysics instruments.

See poster by M. Benjamin
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Summary of LUNAR Components

• Gravitational Physics Lunar Structure via Lunar
  Laser Ranging.
• Low Frequency Radio Heliophysics.
• Low Frequency Cosmology Astrophysics.
• Assessment of other Astrophysics from the Moon.
• Education Public Outreach via planetarium shows
  teacher workshops.

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The Global (sky-averaged) HI Signal
Gas heated above CMB by x-rays
Constraints on Dark Ages Reionization may be
possible from single dipole in orbit above lunar
farside.
Cosmic Twilight Lya flood from first
stars (Wouthuysen-Field Effect)
collisions, gas cools faster than CMB
Jester Falcke, 2009, New Astronomy Reviews, 53,
1.
1 yr integration with Sky-noise limited dipole
Pop III stars
Pop II stars
?Tmin Tsys/(?? t)1/2 where Tsys sky
temperature 17,000 K at 30 MHz
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One Concept Dark Ages Lunar Interferometer (DALI)
DALI concept. (Left, upper right) Possible
location in the Tsiolkovsky crater. (Upper right
insert) Artists concept of lander DALI would
have pallets of rovers instead of an astronaut
habitat module. (Lower right) Individual
station contains 100 electrically-short dipoles.
1000 stations are planned.