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Condensing Solar X-ray and EUV Flare and Coronal Dimming Information Down to a Few Bytes for Lagrange-Point Space Weather Missions

Tom Woods, Frank Eparvier, Andrew Jones, James Mason University of Colorado (CU) Laboratory for Atmospheric & Space Physics (LASP) tom.woods@lasp.colorado.edu (303) 492-4224

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Outline

!  GOES-R EUV and X-ray Irradiance Sensors (EXIS) overview

!  Motivations for compact-EXIS at L5 and L1

!  Capabilities for compact-EXIS = SEEDS

!  Summary & Recommendations

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Space Weather Instrumentation on GOES-R

Figures are from GOES-R Fact Sheets

SUVI Solar EUV Imager

GOES Space Weather Sensors EXIS

Solar EUV & X-ray Irradiance

SEISS In-situ Energetic

Electrons & Protons

Magnetometer & Boom In-situ Magnetic Field

GOES-R 2 large weather sensors 4 small SpWx sensors

!  Space weather sensors have flown on NOAA GOES satellites since the 1970s. "  The four new GOES spacecraft has four space weather (SpWx) sensors, including a

large solar-pointing platform on the articulated solar panels. "  GOES-R+ operations are planned from 2017 to 2034. The solar instruments are not

needed for a L1 mission but could be considered for a L5 mission. The particle and field instruments would be useful for a L1 mission.

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Key Products for Space Weather Operations

Space Weather Product / Alerts

GEO (GOES-16)

Desired Location Research Satellites, Other Satellites L1 L5 L4

Flare: X-ray magnitude XRS # X SDO, PROBA2

Flare: location SUVI & XRS # X SDO, PROBA2

Flare: EUV SUVI & EUVS # X SDO, PROBA2

SEP: forecast with X-rays XRS # X SDO, PROBA2

CME: velocity / mass CD with SUVI CD X X SOHO, STEREO

CME: direction / extent (halo) X X SOHO, STEREO

Forecasts with B fields (desired) X X X SDO, GONG

Forecast with AR features SUVI # X SDO, STEREO

SW & CME Alerts (ρ, B) SEISS X X ACE, DSCOVR, Ground Mag

SW: forecasts cor. holes SUVI # X SDO

GEO Fields & Particles MAG, SEISS

ITM Composition, Winds DMSP, TIMED

Aurora energy, boundary DMSP, TIMED

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Key Products for Space Weather Operations

Space Weather Products / Alerts

GEO (GOES-16)

Desired Location Research Satellites, Other Satellites L1 L5 L4

Flare: X-ray magnitude XRS # X SDO, PROBA2

Flare: location SUVI & XRS # X SDO, PROBA2

Flare: EUV SUVI & EUVS # X SDO, PROBA2

SEP: forecast with X-rays XRS # X SDO, PROBA2

CME: velocity / mass CD with SUVI CD X X SOHO, STEREO

CME: direction / extent (halo) X X SOHO, STEREO

Forecasts with B fields (desired) X X X SDO, GONG

Forecast with AR features SUVI # X SDO, STEREO

SW & CME Alerts (ρ, B) SEISS X X ACE, DSCOVR, Ground Mag

SW: forecasts cor. holes SUVI # X SDO

GEO Fields & Particles MAG, SEISS

ITM Composition, Winds DMSP, TIMED

Aurora energy, boundary DMSP, TIMED

Focus for this talk Note that CD = Coronal Dimming

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GOES-R EUV & X-ray Irradiance Sensors (EXIS) built by CU/LASP

EXIS Metrics Mass 29 kg

Power 31 Watts

X-Band Data Rate 9.7 kbps

L-Band Data Rate 0.7 kbps

Observation Requirement Performance

X-Ray Irradiance

0.05-0.4 nm: 10-9-10-3W/m2;

0.1-0.8 nm: 10-8-4x10-3W/m2

0.05-0.4 nm: 4x10-10-2x10-2W/m2;

0.1-.8 nm: 6x10-10-1.5x10-2W/m2

EUV Irradiance

0-127 nm: 0.1*Solar Min to 10*Solar Max

discrete lines to models 0-127 nm; meets req.

dynamic range

Accuracy XRS: 10% EUVS: 20%

XRS: <7% EUVS: <20%

Cadence XRS: 3 sec EUVS: 30 sec

XRS: 1 sec EUVS: 30 sec

Key Requirements and Performance

Instrument Flight Institution

GOES-R EXIS 1st Launch Nov 2016

LASP

SDO EVE 2010-present LASP

SORCE 2003-present LASP

TIMED SEE 2001-present LASP

Flight Heritage

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Innovations for GOES-R EXIS !  Addition of quad X-ray photometers to XRS

provides monitor of flare location "  Simple design without requiring an imager

!  Development of low-noise (fA) and low-power (0.03 W) electrometer ASIC with digital interface for the EXIS X-ray and EUV diodes

!  Three EUV spectrograph channels to monitor variability of the chromosphere, transition region, and corona

!  Three EUVS channels have on-board tracking for degradation "  EUVS-C: chromospheric Mg II index is

self-calibrated as core-to-wing ratio "  EUVS-B: has chromosphere lines calibrated by

EUVS-C and transition region emissions "  EUVS-A: has transition region lines calibrated by

EUVS-B and coronal emissions

XRS

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Motivations for Compact EXIS at L1-L5

!  On-board, high-cadence monitor of flare magnitude & location without an imager "  GOES-R XRS heritage design "  This info can be used on-board to automate

operations and image selection area

!  Provide coronal dimming data as proxy for CME velocity &mass without an imager "  Key result from SDO EVE, but not learned in

time to be implemented on GOES-R EXIS

!  Provide impulsive phase flare data from He II 304 Å as warning for eruptive flares "  Compact version of GOES-R EUVS-A

!  Provide high-cadence flare results from irradiance instruments that have a very low data rate and thus reduced operations cost

Impulsive PhaseGradual Phase

Coronal DimmingLate Phase

Onset

Fe XXFe XVIFe IXHe II / 10

Time on 2010-May-5 (UT hours)

Figure is from Woods et al. (ApJ, 2011). Table values are from Hock (PhD Thesis, 2012).

Flare C M X Gradual Ph. 100% 100% 100%

Impulsive Ph. 56% 90% 100%

Coronal Dim. 13% 39% 67%

EUV Late Ph. 5% 22% 39%

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Coronal Dimming and CME Relationships !  Cool coronal emission lines, such as Fe IX,

exhibit dimming (darkening) during eruptive flares "  Irradiance coronal dimmings need a correction

for the impulsive phase contribution (Mason et al., 2014) to match EUV image dimming result

"  Mason et al. (2016) analyzed many dimming-CME events to derive relationships

!  CME velocity can be estimated using the coronal dimming slope

!  CME mass can be estimated using the square root of the coronal dimming depth

!  Coronal dimming analysis works best for on-disk events "  On-disk halo CMEs are difficult to analyze in

coronagraph data "  Coronagraphs work best for limb events

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Compact EXIS = SEEDS Solar Eruption Early Detection System

SEEDS & EXIS Comparison SEEDS EXIS

Mass 0.6 kg 29 kg

Power 0.4 Watts 31 Watts

Data Rate 15 bps 9,700 bps

Cadence 30 sec 3 sec XRS 30 sec EUVS

Observation Channel

Flare X-ray Magnitude X-ray 0.1- 2 nm

Flare Location X-ray 0.1-2 nm Quad Diode

Eruptive Flare Monitor He II 304 Å

Solar Position (center) He II 304 Å Quad Diode

Coronal Dimming Monitor (CME proxy)

Fe IX 171 Å (1) Fe IX 171 Å (2)

EUV Late Phase Flare Monitor

Fe XV 284 Å

SEEDS is a re-packaging of GOES-R XRS to have one X-ray channel and four EUV channels.

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Complementary Data from EUV Imager and SEEDS

■  Pros for EUV Imager ■  Tracking Active Regions (AR) ■  Tracking Coronal Holes (CH) ■  Imaging of flares’ eruptive loops

and dimming regions ■  Imaging of flare 4 phases with

well-selected EUV bandpasses

■  Pros for SEEDS ■  Flare magnitude & location can

be used for on-board automation ■  Coronal Dimming is proxy for

CME velocity & mass ■  Flare 4 phases monitored with

small irradiance instrument ■  Low data rates == high cadence

■  Cons for EUV Imager ■  Larger instrument ■  Higher data volume means low

cadence and/or downlinking just eruptive events region

■  Cons for SEEDS ■  No imaging of source regions so

unable to track ARs or CHs ■  “Active Region” magnitude &

location from quad diode is just center of mass of all ARs

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Operations Cost Consideration (in US$ M)

!  Operations cost for L5-L1 missions will likely drive decisions !

Mission Type LEO LEO GEO L1/L5

Mission Purpose CubeSat Sci. Research Res. or Oper. Operations

Communication UHF S-band Ka-band Ka-band

Ground Station Cost $M 0.02 $M 0.5 $M 25 $M 300 x 3

Antenna Dish Size N/A 3 m 18 m 70 m

Number Contacts 2/day 2/day 24-7 continuous 24/day

Data Volume 0.3 MB/day 300 MB/day 1,600,000 MB/day 9,000 MB/day

Average Data Rate 0.004 kB/sec 3.5 kB/sec 18,750 kB/sec 100 kB/sec

Cadence for 2k x 2k image (x2 compression)

11 days 19 min 0.2 sec 40 sec

Operations Cost per Month

$M 0.001 $M 0.06 (NASA NEN)

$M 1.0 (NASA SDO)

$M 4.2 (NASA DSN)

Cost per kiloByte $0.11 $0.01 $0.0001 $0.02

Cost for 3-year Ops $M 0.04 $M 2.2 $M 36 $M 150

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Options to Advance Space Weather Operations

!  Risk Reduction Activities to Support Future Sp Wx Operational Missions "  Develop on-board automation algorithms for L5-L1 planned instruments using

existing instrument data sets from SDO, STEREO, PROBA2 !  For example, SDO EVE has implemented on-board flare trigger for the MEGS

channel using X-ray data from the ESP channel (photometer) "  Fly tech-demo and new research instruments as low-cost LEO missions

!  For example, ESA PROBA2 and NASA-LASP MinXSS CubeSat !  Expanding the Capabilities for Space Weather Operations Beyond GEO

"  What is missing from the GOES Sp Wx measurements ? !  Solar magnetograms for predicting flare and CME probabilities

"  Earth-view magnetograms are currently from SDO HMI and NSF GONG network, so L5 and L4 magnetograms would be more important than one from L1

!  Coronagraphs and Heliospheric Imagers (HI) for CME warnings "  STEREO and SOHO currently provide CME observations, and SO and SSP will

provide HI observations. L5 and L4 are better view for Earth-directed CMEs. "  Coronal dimming from L1, L5, or GEO can also provide CME warnings

!  Solar Wind alerts from L1 is being provided now by DSCOVR "  L5 measurements of solar wind could also provide 1-2 days alerts for solar wind "  Coronal hole measurements from L5 would help with CIR & HSS predictions

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Summary and Recommendations

"  Compact version of EXIS = SEEDS !  Small (~1 Unit) instrument with several space weather products has very

low data rate as desired for Lagrange-Point Space Weather Missions !  High-cadence (1-sec) monitor of flare magnitude and location can be

used on-board to automate the operations and for defining the flaring region data from solar imagers

!  Provide coronal dimming data as proxy for CME velocity and mass !  Provide impulsive phase flare data from He II 304 Å as warning for

eruptive flare events !  Has strong heritage from GOES-R EXIS and SDO EVE

Optimize Critical Measurements from Preferred Location "  GEO (GOES) provides flare alerts and energetic particle alerts "  L1 (DSCOVR) provides solar wind and CME alerts "  L5 & L4 provides CME warnings "  Combined L5, L1, & L4 magnetograms provide flare and CME

forecasts with full-hemisphere (180°) view of the magnetic fields !  Each position is just 60° view of magnetic fields

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BACKUP SLIDES

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Observation Requirement Performance

Coronal Holes Location & Morphology

Fe XV 28.4 nm

Flares Location & Morphology

Fe XVIII 9.4 nm & Fe XX 13.3 nm

CMEs & Active Regions

Coronal Dimming AR Complexity

Fe IX 17.1 nm & Fe XII 19.5 nm

Filaments & Quiet Regions

Location & Complexity

He II 30.4 nm

Angular Res. < 5.0 arcsec 2.5 arcsec / pixel

Cadence < 5 minutes for 3 spectral channels

< 4 minutes for all channels

Key Requirements and Performance GOES-R SUVI

Instrument Flight Institution

GOES-R SUVI 1st Launch Oct 2016

LMSAL

GOES-N SXI 2010-present LMSAL

SDO AIA 2010-present LMSAL

Flight Heritage SUVI Metrics Mass 66 kg

Power 172 Watts (peak) 144 Watts (operational)

X-Band Data Rate 3.5 Mbps

L-Band Data Rate 1 kbps

GOES-R Solar UltraViolet Imager (SUVI) built by LMSAL

Solar EUV

Images

Figures from LMSAL SUVI

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Observation Requirement Performance Low Energy Electrons &

Protons

30eV – 30keV 15 energy bands 5 angular views 30 sec cadence

30eV – 30keV 15 energy bands 12 angular views 1 sec cadence

High Energy Electrons &

Protons

50keV – 4MeV 7 energy bands 5 angular views 30 sec cadence

50keV – 4MeV 11 energy bands 5 angular views 1 sec cadence

Very High Energy Protons

1MeV – 500MeV 10 energy bands 2 angular views 60 sec cadence

1MeV – 500MeV 10 energy bands 5 angular views 1 sec cadence

Energetic Heavy Ions

10-200MeV/ion 5 energy bands

1 direction 5 min cadence

10-200MeV/ion 5 energy bands

1 direction 5 min cadence

Key Requirements and Performance GOES-R SEISS

Instrument Flight Institution

GOES-R SEISS

1st Launch Oct 2016

ATC

GOES-N 2010-present ATC

DMSP SSJ5 1999-present ATC

Flight Heritage SEISS Metrics Mass 74 kg

Power 53 Watts

X-Band Data Rate 24 kbps

L-Band Data Rate 1 kbps

GOES-R Space Environment In-situ Suite (SEISS) built by ATC

Figure from ATC SEISS team

Assurance Technology Corp UNH Space Science Center

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Parameter Requirement Performance

Sensitivity 0.1 nT 0.1 nT

Resolution 0.016 nT 0.01 nT

Range +/- 1000 nT +/- 1000 nT

Cadence 0.5 sec 0.4 sec

Axes 3-axis 3-axis

Key Requirements and Performance for measuring the magnetic field

Flight Heritage Mag Sensor + Boom Metrics Mass 25 kg

Power 5 Watts

X-Band Data Rate 1 kbps

L-Band Data Rate 1 kbps

Instrument Flight Institution

GOES-R/S/T/U Mag Boom

1st Launch Oct 2016 Orbital ATK

GOES-N/O/P Mag Boom 2006-present Orbital ATK

MMS AFG & DFG Magnetometers 2015-present UCLA

GOES-R Magnetometer & 8-m Boom (MAG) built by LM (GOES-R spacecraft vendor)

Figures are from GOES-R website

GOES-R Magnetometer Boom