Data Description

This page summarizes information about the selected resource and its origin based on SPASE metadata.

Table of Contents

  1. Product
  2. Repository
  3. Instrument
  4. Observatory
  5. Persons

SPASE version 2.2.2

Numerical Data Product: SOHO CELIAS 5-min Key Parameter Data

Resource ID
spase://VEPO/NumericalData/SOHO/CELIAS/KP/PT5M Get XML
Name
SOHO CELIAS 5-min Key Parameter Data
Description

Data include 5-min solar wind speed values, heavy ion fluxes in energy bands 0.02-1. MeV/q and 0.5-50 keV/q, and solar EUV photon fluxes from the CELIAS package on SOHO. They are key parameter data accessible from CDAWeb. Scanning CDAWeb plots for the full 1995-2002 time span suggests that only the solar wind flow speed are useful

Additional information
CDAWeb Skeleton Table
Acknowledgement

Please acknowledge the P.I., Peter Bochsler of U. Bern

Contact
Role Person
1. Principal investigator Dr. Peter A. Bochsler Get XML
Release date
2010-08-12 00:00:00
Repository
Name
SPDF Get XML
Availability
Online
Access rights
Open
URL
CDAWeb

With subset, plot and ASCII list functions from CDAWeb

FTP access to files at SPDF
HTTP access to files at SPDF

In CDF via HTTP from SPDF

Format
CDF
File size
47 kB per 1 day
Acknowledgement

Please acknowledge the P.I., Peter Bochsler of U. Bern, and CDAWeb at GSFC/SPDF

Instrument
Charge, Element, and Isotope Analysis System (CELIAS) Get XML
Measurement type
Energetic particles
Thermal plasma
Temporal description
Start date
1995-12-22 00:00:00
Stop date
2002-01-31 00:00:00
Cadence
5 minutes
Observed regions
Heliosphere.NearEarth

Parameters

Parameter #1

Name
Solar wind flow speed
Parameter key
SW_speed
Description

Solar wind plasma flow speed at 5 minute resolution

Cadence
5 minutes
Units
km/sec
Fill value
-1.0e+31
Particle type
Proton
Quantity
Flow speed

SPASE version 2.0.0

Instrument: Charge, Element, and Isotope Analysis System (CELIAS)

Instrument ID
spase://SMWG/Instrument/SOHO/CELIAS Get XML
Name
Charge, Element, and Isotope Analysis System (CELIAS)
Alternate name
CELIAS
Description

This experiment, CELIAS (Charge, Element, and Isotope Analysis System), is designed to study the composition of the solar wind and of solar and interplanetary accelerated energetic particles. It consists of three different particle sensors, each optimized to one of these aspects, plus a fourth sensor to monitor the absolute EUV flux from the sun. The sensors are: Charge Time Of Flight (CTOF), solar wind Mass TOF (MTOF), Suprathermal TOF (STOF), and Solar Extreme-ultraviolet Monitor (SEM). The CELIAS particle energy ranges are designed to complement those of the COSTEP and ERNE experiments also on SOHO. The TOF sensors employ electrostatic deflection systems combined with TOF measurements. The CTOF covers the energy per charge range 0.1--55 KeV/charge, and will determine the composition, charge state distribution, kinetic temperature and speed of the more abundant solar wind ions (e.g., He, C, N, O, Ne, Mg, Si, and Fe). The field of view is a cone of 50 degrees. MTOF is a high-resolution retarding potential mass analyzer with a quadrapole electric field configuration, for measuring the composition of the less abundant elements in the solar wind, and also the isotopic composition of the more abundant heavy ions. The ions within the passband of the electrostatic section pass through a thin carbon foil, where they are scattered and emerge either as neutrals or singly-ionized. Secondary electrons emitted from the foil will generate the start signal, while the ions will generate the stop signal. The STOF is an ion telescope with 0.1 sq cm sr geometric factor. It covers 20--3000 KeV/charge with the electrostatic deflection system, and uses a TOF analysis similar to that of MTOF, plus a final energy measurement in a solid state detector. The SEM consists of a 5000 lines/mm gold transmission grating in front of a set of three absolutely calibrated silicon light diodes, which are covered with an aluminum filter (total thickness 150 nm). The diodes are placed at the zero- and first-order diffraction image of the sun to isolate the 30.4 nm He II line. Due to the extended source of the sun (0.5 degrees) and the 2 mm x 10 mm entrance slit, the spectrometer bandwidth is +/- 4.0 nm. There is a digital processing unit that serves all sensors. It receives, compresses, stores, and formats data for input into the spacecraft telemetry. This information is from the paper ``The Charge, Element, and Isotope Analysis System CELIAS on SOHO,'' by D. Hovestadt (Proceedings of the First SOHO Workshop, ESA SP-348, pp. 39-42, November 1992).

Additional information
NSSDC's Master Catalog

Information about the Charge, Element, and Isotope Analysis System (CELIAS) experiment on the SOHO mission.

Contact
Role Person
1. Principal investigator Dr. Dieter K. Hovestadt Get XML
Release date
2009-05-20 21:10:10
Instrument type
Energetic Particle Instrument
Investigation name
Charge, Element, and Isotope Analysis System (CELIAS) on SOHO
Observatory
SOHO Get XML

SPASE version 2.2.0

Observatory: SOHO

Observatory ID
spase://SMWG/Observatory/SOHO Get XML
Name
SOHO
Alternate name
1995-065A
Solar and Heliospheric Observatory
Description

The primary scientific aims of the Solar and Heliospheric Observatory mission (SOHO) were to investigate: (1) the physical processes that form and heat the Sun's corona, maintain it and give rise to the expanding solar wind; and, (2) the interior structure of the Sun. Imaging and collection of spectroscopic plasma diagnostics of the solar chromosphere, transition region and corona, as well as in situ solar-wind measurements are used to study the corona and solar wind. Solar interior structure is investigated by helioseismological means and by the observation of variations in solar irradiance. SOHO was part of the International Solar-Terrestrial Physics Program (ISTP).

The SOHO spacecraft was three-axis stabilized and pointed towards the Sun with an accuracy of +/- 10 arcsec per 15 min. It consisted of a Payload Module to accommodate the instruments and a Service Module carrying the spacecraft subsystems and solar arrays. SOHO occupied a halo orbit at the Earth-Sun L1 Lagrangian point to obtain uninterrupted sunlight. The design life was two years, but on-board consumables were sufficient for an extra four years of operations.

Twelve instruments comprised the payload, producing a continuous stream of data at 40 kbs, except whenever the solar oscillations imager Michelson Doppler Imager (MDI) was operated in high-bit-rate mode, producing 160 kbs. The high-bit-rate mode was used during scheduled daily eight-hour periods or during dedicated campaigns. Magnetic tape stored data between telemetry contacts with the Experiment Operations Facility, located at NASA-GSFC. For more information, see B. Fleck, V. Domingo, and A. I. Poland, eds., Solar Physics, V. 162, 1995.

SOHO was a joint mission of the European Space Agency and NASA. It was launched aboard an Atlas IIAS rocket from Cape Canaveral Air Station, FL, on Dec. 2, 1995, and mission operations were directed from NASA's Goddard Space Flight Center, Greenbelt, MD.

In April 1998, SOHO successfully completed its nominal two-year mission to study the Sun's atmosphere, surface and interior. Major science highlights include the detection of rivers of plasma beneath the surface of the Sun; the discovery of a magnetic "carpet" on the solar surface that seems to account for a substantial part of the energy that is needed to cause the very high temperature of the corona, the Sun's outermost layer; the first detection of flare-induced solar quakes; the discovery of more than 50 sungrazing comets; the most detailed view to date of the solar atmosphere; and spectacular images and movies of coronal mass ejections, which were being used to improve the ability to forecast space weather.

Contact with SOHO was lost at 23:16 GMT on June 24, 1998 during maintenance operations. The spacecraft went into emergency sun reacquisition mode, which is activated when an anomaly occurs and the spacecraft loses its orientation toward the Sun. When this happened, the spacecraft automatically tried to point itself toward the Sun again by firing its attitude control thrusters under the guidance of an onboard Sun sensor. Efforts to re-establish contact with SOHO did not succeed and telemetry was lost, not to be reestablished for several weeks.

Attitude analysis led to the conclusion that SOHO went into a spin such that the solar panels were nearly edge-on towards the Sun, and thus did not generate any power. Because the spin axis is fixed in space, as the spacecraft progressed in its orbit the orientation of the panels with respect to the Sun gradually changed, resulting in increased solar illumination of the solar arrays as time progressed. On August 3, contact was re-established with SOHO following six weeks of silence. After a lengthy recovery process, on September 16 the spacecraft again locked onto the Sun, and experiment heaters were switched on. After recommissioning of various subsystems, and an orbit correction maneuver, SOHO was finally brought back to normal mode on 25 September at 19:52:58 GMT. Instrument switch-on started October 5, 1998, and by November 4 all instruments were back to normal.

Additional information
NSSDC's Master Catalog

Information about the SOHO mission

Contact
Role Person
1. Project scientist Dr. Arthur I. Poland Get XML
Release date
2010-08-05 18:19:18
Location
Region
Heliosphere.NearEarth

SPASE version 2.2.0

Person: Dr. Peter A. Bochsler

Name
Dr. Peter A. Bochsler
Organization
Universitat Bern
Person ID
spase://SMWG/Person/Peter.A.Bochsler Get XML

SPASE version 2.2.0

Person: Ms. Tamara J. Kovalick

Name
Ms. Tamara J. Kovalick
Organization
GSFC-Code 672
Email
Tamara.J.Kovalick@nasa.gov
Phone
+1-301-286-9422
Person ID
spase://SMWG/Person/Tamara.J.Kovalick Get XML
Release date
2010-08-05 17:35:47

SPASE version 2.2.0

Person: Mr. Robert M. Candey

Name
Mr. Robert M. Candey
Organization
NASA Goddard Space Flight Center
Address
Code 672, Greenbelt, MD 20771, USA
Email
robert.m.candey@nasa.gov
Phone
1-301-286-6707
Person ID
spase://SMWG/Person/Robert.M.Candey Get XML
Release date
2010-08-05 17:35:47

SPASE version 2.2.0

Person: Dr. Robert E. McGuire

Name
Dr. Robert E. McGuire
Organization
NASA Goddard Space Flight Center
Address
Code 672, Greenbelt, MD 20771, USA
Email
mcguire@mail630.gsfc.nasa.gov
Phone
+1 301 286 7794
Person ID
spase://SMWG/Person/Robert.E.McGuire Get XML
Release date
2010-08-05 17:35:47

SPASE version 2.2.0

Person: Dr. Dieter K. Hovestadt

Name
Dr. Dieter K. Hovestadt
Organization
Max-Planck-Institut fur Extraterrestrische
Person ID
spase://SMWG/Person/Dieter.K.Hovestadt Get XML

SPASE version 2.2.0

Person: Dr. Arthur I. Poland

Name
Dr. Arthur I. Poland
Organization
GSFC-Code 682
Email
poland@pal.gsfc.nasa.gov
Phone
+1-301-286-7076
Person ID
spase://SMWG/Person/Arthur.I.Poland Get XML
Release date
2010-08-05 17:35:45

SPASE version 1.3.0

Repository: SPDF

Repository ID
spase://SMWG/Repository/NASA/GSFC/SPDF Get XML
Name
SPDF
Description

Space Physics Data Facility

Additional information
SPDF

Space Physics Data Facility

Contact
Role Person
1. General contact Ms. Tamara J. Kovalick Get XML
2. Technical contact Mr. Robert M. Candey Get XML
3. Project scientist Dr. Robert E. McGuire Get XML
Release date
2008-08-26 21:02:30
Prior IDs
spase://vspo/repository/61
spase://SMWG/Repository/SPDF
Access URL