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STEREO and PLASTIC Level 2 Data

This website serves Level 2 magnetic field and PLASTIC solar wind plasma data.

Magnetic Field Coordinate Systems
In the RTN system, R is radially outward from Sun. T is roughly along the planetary orbital direction; N is northward and the RN plane contains the solar rotation axis. In the spacecraft coordinate system the x-axis is toward the Sun and the y and z axes are oriented south of the spacecraft commesurate with Earth.

Data Availability
Magnetometer data are available beginning November 7, 2006 in RTN coordinates. Processing delays associated with consolidation and validation cause data processing to lag 3 to 4 months behind real time.

Calibrated PLASTIC solar wind moment data are available from February 15, 2007 on STEREO A and from March 1, 2007 on STEREO B. Data generally lags real time by 3 to 4 months. The STEREO solar wind data are a combination of the on-board moment calculation and the 1-dimensional Max calculation with 1D Max taking precedence.

Due to the strain on our system, you may only request up to a year of data at a time.

Available data
  • STEREO A - 2006 Nov 07 00:00:00 UTC to 2026 Jan 01 00:00:00 UTC
  • STEREO B - 2006 Dec 01 00:00:00 UTC to 2014 Sep 27 16:30:00 UTC
Note

Due to issues with our old data-processing hardware, the following columns are only shown as flag values, even though valid data exists, in downloaded and plotted data for dates on or after October 1, 2021:

  • Vp, Np, Tp
  • Vr, Vt, Vn

PLASTIC data only available up to June 30, 2025 and will be updated when available

Spacecraft:
Resolution:
Magnetic Field Coordinate System:
Position Coordinate System:
Columns:




Time Range (UTC):
Start Date End Date

Disclaimer: A file will be generated if at least one data point is available for the selected time range.
Parameter Definitions

Data Resolutions
  • 1 min: One minute data are averages over two minutes centered on each minute.
  • 10 min: Ten minute data are averages over 20 minutes centered on the 10 minute mark.
  • 1 hr: One hour data are average over 2 hours centered on each hour.

Position Coordinate Systems
X, Y, Z, R components of spacecraft position and total heliocentric distance in AU.
  • CARR: Carrington Heliographic coordinates. Z is along the Solar rotational axis, and X is along Carrington prime meridian.
  • HAE: Heliocentric Aries Ecliptic coordinates. X is the first point of Aries, and Z is along the ecliptic north pole.
  • HCI: Heliocentric Inertial coordinates. Z is the solar north rotational axis, and X is the solar ascending node on the J2000 ecliptic.
  • HEE: Heliocentric Earth Ecliptic coordinates. X is the Sun-Earth line, and Z is the north pole for the ecliptic of date.
  • HEEQ: Heliocentric Earth Equatorial coordinates. Z is the solar rotation axis, and X is in the plane containing the Z axis and Earth, at the intersection of the solar central meridian, and the heliographic equator. So, Y is along the cross product of Z and the Sun-to-Earth direction. When converted to longitude and latitude, this is known as Stonyhurst heliographic coordinates.
  • RTN: Radial-Tangential-Normal coordinates. X axis points from Sun center to the spacecraft, and the Y axis is the cross product of the solar rotational axis and X, and lies in the solar equatorial plane (towards the West limb). When the Sun is used as the origin, the designation is HGRTN; with the spacecraft as origin, it is simply RTN.

Column Descriptions
  • Beta: Ratio of the perpendicular plasma (ion plus electron) thermal pressure to the magnetic pressure. A constant electron temperature of 130,000K is assumed. Due to the lack of alpha particle data, we assume its number density is 4% of proton's, and its temperature is 4 times of proton temperature.
  • |B|: Average magnetic field magnitude calculated from individual full resolution magnitudes.
  • Br, Bt, Bn: Average magnetic field component. One minute data are averages over two minutes centered on each minute. Ten minute data are averages over 20 minutes centered on the 10 minute mark. One hour data are average over 2 hours centered on each hour.
  • Br/B, Bt/B, Bn/B: Average direction cosines of the magnetic field computed from normalized components at full resolution.
  • Cone: Angle of the field with the R (antisunward) direction (i.e. acos(BR / BT)). Zero degrees is away from the Sun and 180 degrees is toward the Sun
  • Clock: Angle of the magnetic field in the T-N plane (i.e. atan2(BT, BN)). Zero degree aligned with T. Ninety degrees is aligned with N.
  • Entropy: Logarithm of the 3/2 power over proton temperature to proton density.
  • Np: Interpolated proton number density. See Vp definition for averaging intervals.
  • Total Pr: Sum of magnetic pressure and perpendicular plasma thermal pressure.
  • Mag Pr: Magnetic pressure.
  • Dyn Pr: Solar wind dynamic pressure.
  • Tp: Interpolated proton temperature. See Vp definition for averaging intervals.
  • Vp: Interpolated speed calculated from the three PLASTIC speed samples closest to the minute for one minute data (These cover a two minute span). Ten minute data are averages over 20 one-minute interpolated values centered on the 10 minute mark. One hour data are averages over 2 hours centered on each hour.
  • Vr/V, Vt/V, Vt/V: Average direction cosines of the velocity of solar wind composited every minute and averaged over two minute intervals.