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

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.

- STEREO A - 2007 Feb 01 00:00:00 UTC to 2023 Dec 31 23:49:47 UTC
- STEREO B - 2007 Feb 01 00:00:00 UTC to 2014 Sep 27 16:31:35 UTC

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
- Beta, Total Pr, Magnetic Pr, Dynamic Pr
- Cone Ang, Clock Ang
- BR, BT, BN, NTOTAL
- spacecraft position data (X, Y, Z) in all coordinates

We are working on moving the data processing to a new machine. Meanwhile, we continue to process data using the old hardware, and aren't able to produce the actual values for the above columns.

**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.

**HAE:**X to First Point of Aries; Z to ecliptic north. Angles are ecliptic longitude and latitude.**HEE:**X Sun to Earth; Z ecliptic north. Angles are longitude from Earth and ecliptic latitude.**HEEQ:**Z along solar rotation axis; Y along Z X R; Angles are heliographic longitude and latitude.**CARR:**Z along solar rotation axis. Y perpendicular to Carrington prime meridian; Angles are Carrington longitude and latitude.**RTN:**X Sun to spacecraft; Y perpendicular to plane containing Earth and rototion axis; Angles are zeroes.

**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.**Clock:**Angle of the field with the R (antisunward) direction. Zero degrees is away from the Sun and 180 degrees is toward the Sun.**Cone:**Angle of the magnetic field in the T-N plane. 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.**Pressure:**Sum of magnetic pressure and perpendicular plasma thermal pressure. See comments given for Beta calculation. Magenetic pressure also given separately.**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.