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Data Access
FTPS from SPDF (not with most browsers)
HTTPS from SPDF
CDAWeb
WebService:
CDAWeb Programmatic Data Access
HAPI: CDAWeb HAPI Server
Hawkeye Electric and Magnetic Field Radio Frequency Spectrum Analyzer High Time Resolution
var authors='Gurnett, Donald, A.';
document.write(authors);
(2023).
Hawkeye Electric and Magnetic Field Radio Frequency Spectrum Analyzer High Time Resolution.
[Data set].
Space Physics Data Facility.
https://doi.org/10.48322/etz7-wx98. Accessed on document.write(currentDateStr);.
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ResourceID
spase://NASA/NumericalData/Hawkeye/VLF/PT22S
Description
The CDF file contains approximately 22 second time resolution Electric and Magnetic field data, average magnetic field magnitude, and orbital position data from Hawkeye 1. The VLF experiment measured electric and magnetic fields using a 42.45-m electric dipole (tip-to-tip) which extended perpendicular to the spin axis and a search coil antenna deployed 1.58 m from the spacecraft. The electric field spectrum measurements were made in 16 logarithmically spaced frequency channels extending from 1.78 Hz to 178 kHz, and dc electric fields were also measured. The bandwidth of these channels varied from 7.5% to 30% depending on center frequency. Channel sensitivity and dynamic range were 1E-6 V/m and 100 dB, respectively. A wideband receiver was also used, with two selectable bandwidth ranges: 0.15 to 10 kHz or 1 to 45 kHz. The magnetic field spectrum was measured in eight discrete, logarithmically spaced channels from 1.78 Hz to 5.62 kHz. The bandwidth of these channels varied from 7.5% to 30% depending on frequency. The dynamic range was 100 dB, and the sensitivity ranged from 0.1 nT at 1.78 Hz to 3.4E-4 nT at 5.62 kHz. The wideband receiver described above could be used with the magnetic antenna. Each discrete channel was sampled once every 11.52 s.
Metadata Rights
CC0-1.0:
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available SPASE metadata descriptions. The actual data/software may be subject to a different license.
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Details
Version:2.7.1
NumericalData
ResourceID
spase://NASA/NumericalData/Hawkeye/VLF/PT22S
NamingAuthority
NASA
ResourceType
NumericalData
ResourceHeader
ResourceName
Hawkeye Electric and Magnetic Field Radio Frequency Spectrum Analyzer High Time Resolution
AlternateName
HK_H0_VLF
AlternateName
Hawkeye 1 VLF instrument CDFs at NASA's CDAWeb
DOI
https://doi.org/10.48322/etz7-wx98
ReleaseDate
2025-12-04 13:29:19Z
RevisionHistory
RevisionEvent
ReleaseDate
2021-04-27 15:38:11
Note
Only known prior ReleaseDate of the metadata
RevisionEvent
ReleaseDate
2023-07-30 12:34:56.789
Note
Added DOI and PublicationInfo minted by LFB, metadata versioned up to SPASE 2.6.0, reviewed by LFB 20230727
RevisionEvent
ReleaseDate
2025-10-02 15:11:51Z
Note
Updated PublishedBy name to match ROR Registry. Added ResourceType and NamingAuthority. Changed http to https in top-level schemaLocation attribute. Fixed version number separator in top-level schemaLocation attribute. Matched version number in schemaLocation attribute to updated value in Version tag. ZCB
RevisionEvent
ReleaseDate
2025-12-04 13:29:19Z
Note
Added MetadataRightsList and RightsList(s). Updated to 2.7.1. ZCB
Description
The CDF file contains approximately 22 second time resolution Electric and Magnetic field data, average magnetic field magnitude, and orbital position data from Hawkeye 1. The VLF experiment measured electric and magnetic fields using a 42.45-m electric dipole (tip-to-tip) which extended perpendicular to the spin axis and a search coil antenna deployed 1.58 m from the spacecraft. The electric field spectrum measurements were made in 16 logarithmically spaced frequency channels extending from 1.78 Hz to 178 kHz, and dc electric fields were also measured. The bandwidth of these channels varied from 7.5% to 30% depending on center frequency. Channel sensitivity and dynamic range were 1E-6 V/m and 100 dB, respectively. A wideband receiver was also used, with two selectable bandwidth ranges: 0.15 to 10 kHz or 1 to 45 kHz. The magnetic field spectrum was measured in eight discrete, logarithmically spaced channels from 1.78 Hz to 5.62 kHz. The bandwidth of these channels varied from 7.5% to 30% depending on frequency. The dynamic range was 100 dB, and the sensitivity ranged from 0.1 nT at 1.78 Hz to 3.4E-4 nT at 5.62 kHz. The wideband receiver described above could be used with the magnetic antenna. Each discrete channel was sampled once every 11.52 s.
Acknowledgement
Users please acknowledge the Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center and Hawkeye VLF instrument Principal Investigator Don Gurnett.
PublicationInfo
Authors
Gurnett, Donald, A.
PublicationDate
2023-01-01 00:00:00
PublishedBy
Space Physics Data Facility
Contacts
Role
Person
StartDate
StopDate
Note
1.
PrincipalInvestigator
spase://SMWG/Person/Donald.A.Gurnett
2.
MetadataContact
spase://SMWG/Person/Lee.Frost.Bargatze
InformationURL
Name
Hawkeye Spacecraft
URL
https://spdf.gsfc.nasa.gov/pub/data/hawkeye/documents/archived_website/hawkeye.html
Description
Hawkeye page maintained by NASA GSFC with science and instrument descriptions, data, software, and publication lists
Language
en
InformationURL
Name
NSSDC's Master Catalog
URL
https://nssdc.gsfc.nasa.gov/nmc/experiment/display.action?id=1974-040A-03
Description
Information about the ELF/VLF Receivers experiment on the Hawkeye 1 mission.
PriorIDs
spase://VWO/NumericalData/Hawkeye/VLF/CDF_PT22S
spase://VWO/NumericalData/Hawkeye/VLF/PT22S
spase://VSPO/NumericalData/Hawkeye/VLF/PT22S
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Availability
Online
AccessRights
Open
RightsList
Rights
SchemeURI
https://spdx.org/licenses/
RightsIdentifierScheme
SPDX
RightsIdentifier
CC0-1.0
RightsURI
https://spdx.org/licenses/CC0-1.0.html
RightsName
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products
AccessURL
Name
FTPS from SPDF (not with most browsers)
URL
ftps://spdf.gsfc.nasa.gov/pub/data/hawkeye/h0/vlf/
Description
FTP access to repository of Hawkeye VLF data in CDF format at NASA CDAWeb.
Language
en
AccessURL
Name
HTTPS from SPDF
URL
https://spdf.gsfc.nasa.gov/pub/data/hawkeye/h0/vlf/
Description
In CDF via HTTP from SPDF
AccessURL
Name
CDAWeb
URL
https://cdaweb.gsfc.nasa.gov/cgi-bin/eval2.cgi?dataset=HK_H0_VLF&index=sp_phys
ProductKey
HK_H0_VLF
Description
Repository of Hawkeye data in CDF format at NASA CDAWeb, accessible via web interface. Name of the data resource: HK_H0_VLF.
Language
en
Format
CDF
Encoding
None
AccessDirectoryTemplate
https://cdaweb.gsfc.nasa.gov/pub/data/hawkeye/h0/vlf/$Y
AccessFilenameTemplate
hk_h0_vlf_$Y$m$d_$v.cdf
Acknowledgement
Users please acknowledge Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center and Hawkeye 1 VLF instrument Principal Investigator Don Gurnett.
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF
Availability
Online
AccessRights
Open
AccessURL
Name
CDAWeb Programmatic Data Access
URL
https://cdaweb.gsfc.nasa.gov/WS/cdasr/1/dataviews/sp_phys/datasets/HK_H0_VLF/clientLibraryExample/
Style
WebService
ProductKey
HK_H0_VLF
Description
Access to this data from common programming environments. Note: this AccessInformation element was added by HDPWS.
Format
Binary
Acknowledgement
Users please acknowledge Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center and Hawkeye 1 VLF instrument Principal Investigator Don Gurnett.
AccessInformation
RepositoryID
spase://SMWG/Repository/NASA/GSFC/SPDF/CDAWeb
Availability
Online
AccessRights
Open
RightsList
Rights
SchemeURI
https://spdx.org/licenses/
RightsIdentifierScheme
SPDX
RightsIdentifier
CC0-1.0
RightsURI
https://spdx.org/licenses/CC0-1.0.html
RightsName
Creative Commons Zero v1.0 Universal
Note
CC0 1.0 Universal is the Creative Commons license applicable to all publicly available NASA Heliophysics data products
AccessURL
Name
CDAWeb HAPI Server
URL
https://cdaweb.gsfc.nasa.gov/hapi
Style
HAPI
ProductKey
HK_H0_VLF
Description
Web Service to this product using the HAPI interface.
Format
CSV
Acknowledgement
Users please acknowledge Coordinated Data Analysis Web (CDAWeb) at the NASA Goddard Space Flight Center and Hawkeye 1 VLF instrument Principal Investigator Don Gurnett.
ProcessingLevel
Calibrated
InstrumentIDs
spase://SMWG/Instrument/Hawkeye/VLF
MeasurementType
Waves.Passive
MeasurementType
Spectrum
TemporalDescription
TimeSpan
StartDate
1974-06-08 06:45:10Z
StopDate
1978-04-26 15:59:05Z
Cadence
PT22S
SpectralRange
RadioFrequency
ObservedRegion
Earth.Magnetosphere
ObservedRegion
Earth.Magnetosphere.Polar
ObservedRegion
Earth.NearSurface.AuroralRegion
ObservedRegion
Earth.NearSurface.PolarCap
ObservedRegion
Heliosphere.Inner
Keywords
Dynamic Spectrogram
Spectrogram
AKR
Auroral hiss
Auroral Kilometric Radiation
Terrestrial Kilometric Radiation
TKR
Broad Band Electrostatic Noise
Continuum radiation
Ion Cyclotron Waves
Solar radio burst
Type III Solar radio burst
Parameter #1
Name
Time Line
ParameterKey
Epoch
Description
Center Time of 22 sec averaging period
Cadence
PT22S
Units
ms
Support
SupportQuantity
Temporal
Parameter #2
Name
Magnetic Field Spectral Power Density
ParameterKey
b_spd
Description
Magnetic Field Spectral Power Density at 8 Freq (2 - 5620 Hz): 1.78 Hz, 5.62 Hz, 17.8 Hz, 56.2 Hz, 178 Hz, 562 Hz, 1780 Hz, 5620 Hz
Units
nT**2/Hz
Wave
WaveType
PlasmaWaves
Qualifier
Magnitude
Qualifier
Pseudo
WaveQuantity
Intensity
FrequencyRange
SpectralRange
RadioFrequency
Low
2
High
5620
Units
Hz
Parameter #3
Name
Electric Spectral Power Density
ParameterKey
e_spd
Description
Electric Spectral Power Density at 16 Frequencies (2 Hz - 178 kHz): 1.80 Hz, 5.60 Hz, 17.8 Hz, 56.2 Hz, 178 Hz, 562 Hz, 1780 Hz, 5620 Hz, 13300 Hz, 17800 Hz, 23700 Hz, 31100 Hz, 42200 Hz, 56200 Hz, 100000 Hz, 178000 Hz
Units
(V/m)(V/m)/Hz
Wave
WaveType
PlasmaWaves
Qualifier
Magnitude
Qualifier
Pseudo
WaveQuantity
Intensity
FrequencyRange
SpectralRange
RadioFrequency
Low
2
High
178000
Units
Hz
Parameter #4
Name
Average Magnetic Field Magnitude
ParameterKey
BAVE
Description
Average magnetic Field Magnitude
Field
FieldQuantity
Magnetic
Parameter #5
Name
s/c position in SM lat/local time
ParameterKey
pos_mag
Description
Hawkeye position in Earth radii, SM magnetic latitude, SM magnetic local time
Structure
Size
3
Element
Name
RE
Index
1
Units
Re
ValidMin
0.0
ValidMax
22.0
Element
Name
SM_LAT
Index
2
Units
Deg
ValidMin
-90.0
ValidMax
90.0
Element
Name
SM_LT
Index
3
Units
Hour
ValidMin
0.0
ValidMax
24.0
Support
SupportQuantity
Positional
Parameter #6
Name
Cartesian Position GSM
ParameterKey
pos_GSM
Description
Cartesian Position GSM
Units
RE
CoordinateSystem
CoordinateRepresentation
Cartesian
CoordinateSystemName
GSM
Structure
Size
3
Element
Name
X_GSM
Index
1
Element
Name
Y_GSM
Index
2
Element
Name
Z_GSM
Index
3
ValidMin
-22.0
ValidMax
22.0
Support
SupportQuantity
Positional
Parameter #7
Name
Active vs Passive Indicator
ParameterKey
activity_index
Description
Active (=1) vs Passive (=0) Indicator. Active emissions only affect the Electric Field measurements at 17.8 Hz and 56.8 Hz
Support
SupportQuantity
Other
Parameter #8
Name
Frequency (E field)
ParameterKey
e_freq
Description
16 Electric Field assoc Frequencies (2Hz - 178kHz): 1.8 5.6 17.8 56.2 178.0 562.0 1780.0 5620.0 13300.0 17800.0 23700.0 31100.0 42200.0 56200.0 100000.0 178000.0
Units
Hz
Support
SupportQuantity
Other
Parameter #9
Name
Freq band width (E field)
ParameterKey
e_freq_delta
Description
Electric Field associated Frequency band width (16 channels): 1.4 0.8 6.6 13.2 35.0 151.4 415.1 1178.0 439.0 493.5 778.5 581.0 779.5 1129.5 2464.5 2804.5
Units
Hz
Support
SupportQuantity
Other
Parameter #10
Name
Noise associated with E field
ParameterKey
e_noise
Description
Electric Field associated Noise (16 channels)
Units
(V/m)(V/m)/Hz
Wave
WaveType
PlasmaWaves
Qualifier
Magnitude
Qualifier
Pseudo
WaveQuantity
Intensity
FrequencyRange
SpectralRange
RadioFrequency
Low
2
High
178000
Units
Hz
Parameter #11
Name
Frequencies (B field)
ParameterKey
b_freq
Description
8 Associated Magnetic Field Freq (1.78 - 5620 Hz): 1.78 5.62 17.8 56.2 178.0 562.0 1780.0 5620.0
Units
Hz
Support
SupportQuantity
Other
Parameter #12
Name
Freq Band Width (B field)
ParameterKey
b_freq_delta
Description
8 Freq Band widths B field (1.565 - 1266 Hz): 1.565 0.96 6.64 12.04 36.565 154.9 517.0 1266.0
Units
Hz
Support
SupportQuantity
Other
Parameter #13
Name
Noise associated with B field
ParameterKey
b_noise
Description
Noise associated with B field (8 - channels): 0.004425 4.853E-5 7.793E-7 5.72E-8 8.993E-9 8.854E-10 3.912E-10 3.784E-10
Units
nT**2/Hz
Wave
WaveType
PlasmaWaves
Qualifier
Magnitude
Qualifier
Pseudo
WaveQuantity
Intensity
FrequencyRange
SpectralRange
RadioFrequency
Low
2
High
5620
Units
Hz