Direct Imaging Black Holes from LEO
Ref Bari | 06/17 Update
Metrics and motivations for Earth–space VLBI: Time-resolving Sgr A* with the Event Horizon Telescope (Palumbo et. al., ApJ 2019)
Todd Ely
Joseph Lazio
Eric Burt
Ben Hudson
Luke Anderson
Rick Fleeter
Original Mission
Descoped Mission
Descope Mission #2
OG
Descoped Mission
Descope Mission #2
OG
DS1
Descope Mission #2
OG
DS1
DS2
Antenna
Cryocooler
Frequency Reference System
Antenna
Cryocooler
Frequency Reference System
Antenna
RSP2
Frequency Reference System
Antenna
RSP2
USO
Antenna
RSP2
USO
3C 84
NRAO 530
NGC 1052
BL Lac
3C 273
3C 84
NRAO 530
NGC 1052
BL Lac
3C 273
3C 84: Nucleus of galaxy NGC 1275 (22 GHz)
NRAO 530
NGC 1052
BL Lac
3C 273
3C 84
NRAO 530: Quasar 230 GHz, 20 μas (EHT)
NGC 1052
BL Lac
3C 273
3C 84
NRAO 530
NGC 1052: Bright Elliptical Galaxy (65 mln lys)
BL Lac
3C 273
3C 84
NRAO 530
NGC 1052
BL Lac
3C 279: An 'optically violent' variable quasar
Gamma Ray Image
3C 84
NRAO 530
NGC 1052
BL Lac
3C 273
LT-RSP2 Cryocooler
Raytheon long life cryocoolers for future space missions (T. Conrad et. al., Cryogenics 2017)
Stirling Cryocooler
Development of Advanced Two-Stage Stirling Cryocooler for Next Space Missions (Y. Sato et. al., Cryocoolers 15, 2009)
Stirling Cryocooler
Development of Advanced Two-Stage Stirling Cryocooler for Next Space Missions (Y. Sato et. al., Cryocoolers 15, 2009)
Stirling Cryocooler
Development of Advanced Two-Stage Stirling Cryocooler for Next Space Missions (Y. Sato et. al., Cryocoolers 15, 2009)
Phase Error
Observing Frequency
Timing Jitter
Allan Deviation
Integration Time
Integration Time
Coherence Loss
Observing Frequency
Integration Time
Allan Deviation
Allan Deviation
ABRACON SMD OCXO
Allan Deviation
ABRACON SMD OCXO
Allan Deviation
ABRACON SMD OCXO
🕒 Prospective Timeline
June
July
August
September
🕒 Prospective Timeline
June
July
August
September
🕒 Prospective Timeline
June
July
August
September
🕒 Prospective Timeline
June
July
Aug
September
🕒 Prospective Timeline
June
July
Aug
Sep
🕒 Prospective Timeline
Antenna
🕒 Prospective Timeline
Cryocooler
🕒 Prospective Timeline
Solar Panels
🕒 Prospective Timeline
Orbital Parameters
🕒 Prospective Timeline
Data Downlink
🕒 Prospective Timeline
Systems Integration
💰Funding Oppurtunities
June
$3,000
💰Funding Oppurtunities
July
$175,000
$3,000
$175,000
💰Funding Oppurtunities
Sep
$175,000
$3,000
$250,000
💰Funding Oppurtunities
Oct
$175,000
$3,000
$250,000
💰Funding Oppurtunities
🎯 Mission Statement
🎯 Mission Statement
🎯 Mission Statement
Secondary
Science Targets
Gaussian Source Approximation
Visibility Amplitudes
Thermal Noise Constraints
SEFD Constraint
Constraints
Parameter Space
Antenna Diameter + Temperature!
Delta
Delta
Delta
Delta
Delta
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
Goal:
🧠 The (u,v) Plane
Intensity of a certain part of the sky/
sky brightness pattern
Goal: Measure
🧠 The (u,v) Plane
Goal: Measure
Coordinates in the sky
🧠 The (u,v) Plane
Now we add the effects of the radio interferometer ...
Coordinates in the sky
🧠 The (u,v) Plane
Now we add the effects of the radio interferometer ...
Multiplicative envelope:
comes from size of antennas
🧠 The (u,v) Plane
Now we add the effects of the radio interferometer ...
Simulates interference pattern
🧠 The (u,v) Plane
Now we add the effects of the radio interferometer ...
(u,v): Baseline vector
u: East-west baseline distance
v: North-south baseline distance
🧠 The (u,v) Plane
Take all the signals from the sky and add them up ...
🧠 The (u,v) Plane
Take all the signals from the sky and add them up ...
Visibility Function
🧠 The (u,v) Plane
Take all the signals from the sky and add them up ...
Multiplicative Envelope
🧠 The (u,v) Plane
Take all the signals from the sky and add them up ...
Sky Intensity/Brightness
🧠 The (u,v) Plane
Take all the signals from the sky and add them up ...
Interferometric Pattern
🧠 The (u,v) Plane
It's a Fourier Transformation!
One pair of antennas measures one single point on the (u,v) plane: one fourier mode!
🧠 The (u,v) Plane
It's a Fourier Transformation!
What we want
🧠 The (u,v) Plane
It's a Fourier Transformation!
What we get :(
🧠 The (u,v) Plane
It's a Fourier Transformation!
Fill up the (u,v) plane
and then fourier transform back to the real image!
🧠 The (u,v) Plane
It's a Fourier Transformation!
Fill up the (u,v) plane
and then fourier transform back to the real image!
🧠 The (u,v) Plane
But how do you fill up the (u,v) plane?
🧠 The (u,v) Plane
But how do you fill up the (u,v) plane?
🧠 The (u,v) Plane
🧠 The (u,v) Plane
🧠 The (u,v) Plane
But how do you fill up the (u,v) plane?
2. Earth Rotation Aperture Synthesis
🧠 The (u,v) Plane
2. Earth Rotation Aperture Synthesis