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December 27, 2010 Space Weather Prediction Center (SWPC) ACE Real-Time Solar Wind (RTSW) DATA LISTS 1- and 5-min ACE RTSW data lists: Anonymous FTP ftp.swpc.noaa.gov/pub/lists/ace Web http://www.swpc.noaa.gov/ftpmenu/lists/ace.html Hourly data & Satellite Location: Anonymous FTP ftp.swpc.noaa.gov/pub/lists/ace2 Web http://www.swpc.noaa.gov/ftpmenu/lists/ace2.html ACE RTSW Plots and Ground Station Tracking: http://www.swpc.noaa.gov/ace/ Older ACE RTSW Announcements are shown at the bottom of this file. ****************************************************************** ** Please read the SWPC Disclaimer at http://www.swpc.noaa.gov/ ** ****************************************************************** SWPC provides near-real-time and recent data, solar and geomagnetic indices and solar event reports created from preliminary reports. Preliminary data may contain errors or be revised after further review. The historical products in this SWPC Warehouse are the preliminary reports as originally published. SWPC does not encourage the use of preliminary data for research purposes. Links to on-line data at SWPC and archive sites with final data: http://www.swpc.noaa.gov/Data/ ****************************************************************** Please send comments and questions to SWPC.Webmaster@noaa.gov Report problems to SWPC.CustomerSupport@noaa.gov ******************************************************************************** ******************************************************************************** Real-Time Solar Wind (RTSW) data from the Advanced Composition Explorer (ACE) spacecraft are made available by the Space Weather Prediction Center (SWPC) as updating data lists and plots. The plots and more information is available at the SWPC Web site: http://www.swpc.noaa.gov/ace/index.html --- ACE RTSW Instruments --- Average Intervals MAG - Magnetometer 1-min and 1-hour SWEPAM - Solar Wind Electron Proton Alpha Monitor 1-min and 1-hour EPAM - Electron Proton and Alpha Monitor 5-min and 1-hour SIS - Solar Isotope Spectrometer 5-min and 1-hour All data lists are ASCII text files with a standard SWPC data list format. There are two lists for each of the four ACE instruments; a 2-hour list and a daily list. The 2-hour lists contain the most recent data from the instrument and are updated in near-real-time. The Magnetometer and SWEPAM data is available as 1-min averages and updated once a minute. The EPAM and SIS data is available as 5-minute averages and updated once every 5 minutes. The Daily lists for all instruments are updated once a hour beginning 0101UT daily. NOTE: Previous or missed ACE data is never available to SWPC. Therefore SWPC data lists are never altered once the period is complete. --- File Naming Conventions --- The filenames for the 2 hour lists do not change. Users retrieving data frequently are requested to use these short files. ace_mag_1m.txt ace_swepam_1m.txt ace_epam_5m.txt ace_sis_5m.txt The daily lists have the UT date prefixed to the basic filename. For example 20071101_ace_mag_1m.txt is the filename for ACE Magnetometer data on November 1, 20077. 20071101_ace_mag_1m.txt 20071101_ace_swepam_1m.txt 20071101_ace_epam_5m.txt 20071101_ace_sis_5m.txt HOUR DATA FILES in /ace2 directory Filenames: yearmonth_ace_instrument_1h.txt, e.g. 200710_ace_mag_1h.txt, 200710_ace_sis_1h.txt, 200710_ace_swepam_1h.txt 200704_ace_epam_1h.txt Update: Hourly data files are updated at 10 minutes past the hour. --- Retention --- Daily files of 1-min and 5-min data are retained for 30 days. Monthly files of hourly values are retained for 1 year. --- File format --- o The file format follows a standard data list conventions where header lines start with either # or :. o The lines following the header (# and :) lines are data records, there are no header lines after the data begins. o The file ends with the last data record. o There is a data record for each time interval. For example, a completed daily 5-min file contains 288 data records -- one for each 5 minute interval in the day. When no data are available there is a record containing missing data values for that interval. o Fields within each record are delimited by white space. Records are written with a formatted write statement so the field widths do not change. However, SWPC reserves the right the change the format as needed. --- Valid Data --- The header lines on each list identify the data values, units, and missing data values. The range of valid values are shown in the instrument descriptions below. --- Date/time fields for all data lists --- Dates are shown as year month day (2003 09 06) and "Modified Julian Day (MJD) as defined in an early SWPC database. The SWPC MJD for Jan 1, 2003 is 52640 The SWPC MJD for Jan 1, 2004 is 53005 Time is shown as HourMin (0035) and seconds of the day (2100) --- Status Flags --- Status fields for all instruments are a one digit integer from 0 through 9 where 0 = nominal data, 9 = no data, and 1-8 indicate bad data. More specifically: 0 = Data values a nominal 1 = SWEPAM data flag non-zero 2 = Spacecraft attitude may be in error (following a maneuver) 3 = SWEPAM mode is bad 4 = The magnetometer flip bit is on, data are not processed 5 = The magnetometer is in calibration mode, data are not processed during calibration 6 = Some values in the data record were out of their valid range, unable to to process the data 7 = Some values in the data record were missing, unable to process the data 8 = The data record was incomplete, unable to process the data 9 = No data were received at SWPC, usually because no site was tracking ACE --- SPACECRAFT LOCATION FILES in /ace2 directory --- Filenames: yearmonth_ace_loc_1h.txt, e.g.200306_ace_loc_1h.txt Updates: Current month is recreated daily at 0012UT. SWPC uses predicted ACE spacecraft location information to create a monthly list of hourly predicted locations. Files contain values from the 1st of the month through hour 23 of the current day. The hourly predicted location values are X, Y, and Z position in GSE coordinates, with an accuracy 0.1 earth radii (about 600 km). -------------------------------------------------------------------------------- MAG - Magnetometer Description Format Units min/max IMF X-component in GSM coordinates Float nT -200.0 / 200.0 IMF Y-component in GSM coordinates Float nT -200.0 / 200.0 IMF Z-component in GSM coordinates Float nT -200.0 / 200.0 IMF component magnitude Float nT 0.0 / 200.0 IMF latitude in GSM coordinates Float degrees -90.0 / 90.0 IMF longitude in GSM coordinates Float degrees 0.0 / 360.0 -------------------------------------------------------------------------------- SWEPAM - Solar Wind Electron Proton Alpha Monitor Description Format Units min/max Solar wind proton density Float p/cc 0.0 / 200.0 Solar wind bulk speed Float km/s 200.0 / 2000.0 Solar wind ion temperature Float degrees K 1.00E4 / 1.00E7 Solar wind vector velocity in GSE x-direction Float km/s -2000.0 / -200.0 Solar wind vector velocity in GSE y-direction Float km/s -200.0 / 200.0 Solar wind vector velocity in GSE Z-direction Float km/s -200.0 / 200.0 -------------------------------------------------------------------------------- EPAM - Electron Proton and Alpha Monitor Description Format Units min/max Differential electron flux 38-53 keV Float p/(cm2-sec-ster-MeV) 0.00/1.0E8 Differential electron flux 175-315 keV Float p/(cm2-sec-ster-MeV) 0.00/1.0E7 Differential proton flux 47-68 keV Float p/(cm2-sec-ster-MeV) 0.00/1.0E8 Differential proton flux 115-195 keV Float p/(cm2-sec-ster-MeV) 0.00/1.0E7 Differential proton flux 310-580 keV Float p/(cm2-sec-ster-MeV) 0.00/1.0E7 Differential proton flux 1060-1900 keV Float p/(cm2-sec-ster-MeV) 0.00/1.0E6 FP6p (761-1220 keV proton flux) Float p/(cm2-sec-ster-MeV) 0.00/1.0E7 Anisotropy Index Float Dimensionless 0.0/2.0 *** Special Note on EPAM Proton Data: *** The EPAM LEMS120 instrument which provides proton data in the energy ranges 47-68, 115-195, 310-580, and 1060-1900 keV is oriented on the ACE spacecraft at 120 degrees off the sun-Earth line, back towards the Earth. A consequence of this is that "upstream" magnetospheric particle bursts are often seen in these data. These bursts are most noticeable in the lower energy ranges, can occur several times a day, and can last for tens of minutes. The proton data in the 761-1220keV range is derived from a different instrument (CA60) oriented more towards the sun and is typically not affected by these upstream bursts. -------------------------------------------------------------------------------- SIS - Solar Isotope Spectrometer Integral Flux of High-energy Solar Protons Description Format Units min/max Integral proton flux at >10 MeV Float p/(cm2-sec-ster) 0.00 / 1.00E5 Integral proton flux at >30 MeV Float p/(cm2-sec-ster) >0.00 / 1.00E5 -------------------------------------------------------------------------------- ACE Spacecraft Location Description Format Units min/max X position in GSE coordinate (Earth radii) Float Re 0.0 / 300.0 Y position in GSE coordinate (Earth radii) Float Re -200.0 / 200.0 Z position in GSE coordinate (Earth radii) Float Re -200.0 / 200.0 ================================================================================= ================================================================================= ACE RTSW Announcements ========================================================================== October 19, 2010 -- Based on the advice of the ACE EPAM science team, the EPAM FP6p proton channel energy range shown in headers was corrected from 761-1220 keV to 795-1193 keV. ========================================================================== ACE Real-time Solar Wind Data Resumes Nov 25, 1910UT Nov 25, 2009 -- The ACE Real-time Solar Wind data was unexpectedly interrupted from 1837UT Nov 24 until 1900UT Nov 25. ================================================================== June 1, 2006 ACE RTSW SWEPAM Data Improvement The ACE RTSW SWEPAM data processing was updated at 0000 UTC June 1, 2006. This change will result in improved solar wind parameters (speed, density, and temperature) that more closely match ACE Science Center data. ACE RTSW MAG, EPAM, and SIS data are unaffected. ================================================================== May 5, 2006 ACE RTSW SWEPAM Data Improvement At 0000 UTC on June 1, 2006, the ACE RTSW SWEPAM data processing will be updated. This change will result in improved solar wind parameters (speed, density, and temperature) that more closely match ACE Science Center data. The most significant impact will be higher RTSW density values during low-speed, low-density solar wind conditions. ACE RTSW MAG, EPAM, and SIS data are unaffected. ================================================================== May 15, 2006 ACE RTSW Data Timing Problem Resolved From 1300UT May 12 to 1300 UT May 13 there was a problem in the SEC ACE RTSW data. Values were correct but the associated time tags were about 15 minutes earlier than the actual reading. ================================================================== April 3, 2006 Termination of ACE Solar Wind Data a comment period for the proposed NWS Termination of ACE Solar Wind Data was April 3 - May 18, 2006 ================================================================== September 12, 2005 ACE SOLAR WIND DATA CONTAMINATION ENDS Recent solar energetic proton fluxes which had contaminated the ACE SWEPAM instrument data have subsided. The period of ACE contamination was about 1300 UTC, 09 September to 1000 UTC, 11 September. ================================================================== Sept 09, 2005 ACE SOLAR WIND DATA CONTAMINATED Recent solar energetic proton events have contaminated the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC. This contamination started at about 1300 UTC on 09 September and is expected to continue until energetic proton fluxes subside. ================================================================== May 19, 2005 SIS DATA noise There is currently noise in the SIS RTSW proton rates. The SIS team is investigating the cause and expects it to be corrected in the next few days. ================================================================== January 24, 2005 ACE SOLAR WIND DATA CONTAMINATED Recent solar energetic proton events contaminated the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC. There were essentially two outages due to the proton events: Jan 17 13:22 -- Jan 18 22:40 UTC Jan 20 07:00 -- Jan 21 17:00 UTC =========================================================================== August 24, 2004 ACE MAG Data Processing Change ACE MAG data processing was updated at 0000 UTC on 24 August, 2004. This update should result in improved RTSW magnetic field values that more closely match ACE Science Center data. =========================================================================== February 4, 2004: Real-time proton data from the EPAM LEMS30 instrument has been replaced with similar proton data from the LEMS120 sensor. The new proton channels cover the following energy ranges: 47-68 keV, 115-195 keV, 310-580 keV, and 1.06-1.9 MeV. Previous real-time electron (38-53, 175-315 keV) and proton (0.761-1.22 MeV) data from the EPAM CA60 telescope remain unchanged. Plots and Data Lists of 5-minute and 1-hour averaged data were backfilled to January 29, 2004. =========================================================================== January 15, 2004 SEC is proceeding to switch the ACE RTSW EPAM proton data processing to another sensor. The operational switch over to the new sensor data has been reschedule to February 4, 2004. It is anticipated that the following proton energy ranges will be available: 47-68 keV (P1'), 115-195 keV (P3'), 321-587 keV (P5'), and 1060-1900 keV (P7'). November 12, 2003 As a result of the last two weeks of high solar activity several of the RTSW EPAM proton channels have become abnormally high and have shown excessive noise. As a result the data from the 65-112 keV (P2), 112-187 keV (P3), and 310-50 keV (P5) energy channels have been removed from the real-time plots and lists. The 1060-1910 keV (P7) channel remains but has also begun to show noise. The 761-1220 (W1) proton channel and electron channels, being from another EPAM sensor, have been unaffected. SEC is investigating the switch to another EPAM proton sensor for its RTSW data stream. =========================================================================== November 4, 2003 ACE SOLAR WIND DATA CONTAMINATION ENDS The solar energetic proton event that contaminated the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC Nov 2-3 ended November 3 about 2040UT. ========================================================================== November 3, 2003 ACE EPAM Data Problems On October 29 the ACE EPAM 65-112 keV (P2) and 112-187 keV (P3) energy channels became spuriously high following the onset of a large solar energetic particle event and have not returned to nominal values. In addition, the 310-580 keV (P5) channel became elevated and erratic on November 1 and 2 during a second solar energetic particle event. The P5 channel appears to have recovered; however, this does not preclude similar problems in the future. The EPAM instrument team and SEC are investigating the cause of these problems and a possible cure. Look for more information here as information becomes available. ACE SOLAR WIND DATA CONTAMINATED A solar energetic proton event is contaminating the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC. The contamination begin Nov 2 at 1820 UTC. ========================================================================== October 31, 2003 ACE SOLAR WIND DATA CONTAMINATION ENDS The solar energetic proton event that contaminated the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC Oct 28 - 30 ended October 31 about 0052 UTC. ========================================================================== October 28, 2003 ACE SOLAR WIND DATA CONTAMINATED A solar energetic proton event is contaminating the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC. The contamination begin Oct 28 at 1242 UTC. ======================================================================== March 31, 2003 Technical difficulties at CRL resulted in an ACE data outage from March 30, 2300UT to March 31, 0700UT. Alternative coverage has been arranged until the CRL problem is corrected. ======================================================================== March 18, 2001 ACE EPAM Data Processing Changed ACE EPAM data processing was updated. The visible change was replacing the noisy Proton 47 to 65 keV data with the 65 to 112 keV data in EPAM lists and plots. ======================================================================== March 5, 2002 EPAM Data Processing Change On March 18, 2002 EPAM data processing will be updated. On data lists, the header line changes to show the new energy range for the first Proton channel. On data plots, the legend changes. EPAM data processing update: In late November and early December 2001 the P1 channel (47 to 65 keV) data increased during an energetic particle event (small radiation storm) and never returned to nominal levels. The channel became "noisy" and after monitoring for a few weeks the decision was made to replace the P1 channel with the P2 channel (65 to 112 keV) data, the next higher energy channel within the same detector on EPAM. During the later part of December 2001 the P5 channel (310 to 580 keV) showed anomalous periods of increased particle flux. The instrument PI from JHU/APL determined that when the detector was pointed in the general direction of the sun, the sector pointed toward the sun showed large increases in particle flux. This is believed to be due to solar contamination and only happens during limited times between each set of spacecraft maneuvers. The decision was to change the processing of all channels from this detector to eliminate the solar noise problem. A third problem was induced by the solar noise problem: Whenever the P5 channel became noisy the P1 and P3 data would drop out. The cause of the drop out was a programming filter designed to eliminate "bad" data. Since not all of the data were "bad", only the sunward directed sector, a decision was made to eliminate all data from the sunward sector. Problems two and three were solved by the removal of the data from the sunward sectors for all channels. The only impact from removing the sunward sector data is larger fluctuations in the data when the flux is near background levels. ======================================================================== March 4, 2002 ACE Tracking Reduced RAL will not be tracking for 3 weeks starting March 5 while their antenna is upgraded. ======================================================================== January 25, 2002 CRL to lose tracking for 2 days Tracking from CRL will be unavailable starting at 21:42 UTC on 25 January until 21:37 UTC on 27 January. EPAM lowest energy channel (P1) 47-65 keV data are suspect since late November. This channel will be replaced by late February. Possible cures are being investigated by the instrument team and SEC. ======================================================================== December 20, 2001 ACE EPAM P1 Channel Data Suspect Data from the ACE EPAM lowest energy channel (P1) 47-65 keV are suspect since late November, following the large proton event that ended on the 24th. The cause and possible cure are being investigated by the instrument team and SEC. Look for further messages here as more information becomes available. ======================================================================== November 26, 2001 ACE SOLAR WIND DATA CONTAMINATION ENDS The solar energetic proton event that contaminated the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC on November 23 and 24 ended November 24 about 1800 UTC. ======================================================================== November 7, 2001 ACE SOLAR WIND DATA CONTAMINATION ENDS A solar energetic proton event contaminated the ACE SWEPAM instrument data resulting in incorrect solar wind density, speed, and temperature values being reported by SEC on November 5 and 6. The contamination ended November 7 about 0300 UTC. ======================================================================== 1545 UTC Sept 27, 2001 ACE DATA RETURNS TO NOMINAL A solar energetic proton event which was contaminating the ACE SWEPAM instrument has subsided. ACE solar wind density, speed, and temperature values reported by SEC are now correct. The values were incorrect from 1602 UTC on 24 Sept until 0945 UTC on Sept 27th. ======================================================================== July 27, 2001 ACE SPACECRAFT MANEUVER COMPLETED NASA performed a Z-axes maneuver, to keep the Spacecraft in L1 orbit. ACE Real-Time Solar Wind data was unavailable from 1534 UTC July 23th until 1825 UTC July 26, 2001. ======================================================================== July 26, 2000 ACE EPAM Data Lists Header Line Changes The ACE EPAM 5-min data lists, had incorrect Differential Proton Flux ranges. The header lines were changed beginning 26 July 2000. CORRECTED: # -- Differential Flux -------------------------- # UT Date Time ------------------ Protons keV ---------------- # YR MO DA HHMM 47-65 112-187 310-580 761-1220 1060-1910 INCORRECT: # -- Differential Flux -------------------------- # UT Date Time ------------------ Protons keV ---------------- # YR MO DA HHMM 56-78 130-214 337-594 761-1220 1073-1802 ================================================================== July 30, 1998 ACE Hourly Averaged data SEC creates monthly files of hourly averaged data from each of the ACE instruments. The files are updated every 3 hours beginning at 0010UT. The current month's files are recreated at each run. The previous month's files is created for the last time on the first day of the new month. ======================================================================== July 28, 1998 The EPAM 761-1220 MeV Proton algorithm was adjusted at 7/28 1600UT. There was factor of 3 decrease which matches expected values. ======================================================================== 4/3/98 Update on quality of ACE RTSW data sets MAG: All data nominal SWEPAM: All data nominal. When the velocity of the solar wind falls to low values the current algorithm will often set a flag indicating a problem exists. SEC flags the data in the data base and does not plot the data on the web site. The end result is a number of missing data at the one minute cadence. EPAM: All differential flux channels nominal, except for W1. This channel is impacted by above normal temperatures on ACE. APL is looking at this issue. The only impact is the anisotropy index is not valid. The energy range of this channel is covered by the other existing channels. SIS: Both integral channels nominal. Integral flux is at background until a large event is detected Update on tracking: RAL, NASA, and AFSCN are fully operational. CRL is down for antenna repair and is expected up in two months. AFSCN has added extra tracking coverage during the time period normally covered by CRL. Occasionally short dropouts occur during a tracking pass, usually due to data transmission problems. Bad data records are received during some tracking passes. Software eliminates most of the problem data, but not all problem data. ========================================================================= 2/9/98 - A software solution to the SWEPAM instrument problem was installed on 2/5. Density, Bulk Speed and Ion Temperature data now appear nominal. 2/2/98 - The Spacecraft Location files will not be available until March. 2/2/98 - The Magnetometer data is still in spacecraft coordinates (RTN). Will not be switched to GSM coordinates in March. 2/2/98 - Lists of hourly average will not be available until March. 2/2/98 - The limits shown below for Mag component magnitude, SWEPAM bulk speed, SWEPAM X vector velocity, and Xgse location were corrected 2/2/98. 1/21/98 - Operational ACE data lists began running.