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CRCSS Space Science Research : 

CRCSS Space Science Research

Slide10: 

International Collaboration

CRCSS Space Science Research: 

CRCSS Space Science Research Objectives of the NewMag experiment: (i) Conduct basic research on the structure/dynamics of the ionosphere, exosphere/inner plasmasphere using magnetic field observations. (ii) Study the dynamics of field aligned currents and filamentary structures in the auroral zones, and the equatorial electrojet current system. (iii) Study oscillating wave fields and their variability in the ionosphere and exosphere, including lower ELF band ion cyclotron waves and ULF (ultra-low frequency) hydromagnetic waves in conjunction with Antarctic and middle/low latitude ground station observations. (iv) Contribute to the monitoring and mapping of the geomagnetic field in the Australian region. (v) Apply the results to plasma diagnostics and where relevant space weather modelling.

CRCSS Space Science Research: 

CRCSS Space Science Research Field-Aligned Currents The behaviour of a magnetised plasma can be described in terms of the configuration of the magnetic field or the currents that are flowing This relates to the magnetospheric current systems. The currents flowing near midnight around the onset of substorms, are believed to arise from the rapid reconfiguration of the tail when magnetic reconnection in the tail begins. There is not consensus on the mechanisms by which these stresses arise. Also important will be correlation with ground observations made at the Australian Antarctic stations of Davis, Casey and Mawson, and the USA Automatic Geophysical Observatories located on the southern polar cap.

CRCSS Space Science Research: 

CRCSS Space Science Research Ultra-low Frequency (ULF) Waves Ultra-low frequency (ULF) waves, naturally occurring plasma waves in the 1 mHz - 5 Hz band, are seen in all regions of the magnetosphere from high to equatorial latitudes Many types of ULF waves are also transmitted from the magnetosphere through the ionosphere to the ground. Since the ionosphere acts as a "short circuit" or sink for many magnetospheric phenomena, ground-based and ionospheric signatures play an important role in understanding the interactions with solar energy sources.

CRCSS Space Science Research: 

CRCSS Space Science Research Interactions that will be observed by the FedSat NewMag and Antarctic and other ground stations include flux transfer events (FTEs) which are signatures of transient dayside reconnection and solar wind pressure and other variations. The more regular Pc3-5 ULF waves in the 1-100 mHz band are generally observed signatures of resonances in the magnetosphere. Through M-I coupling NewMag will be looking for lower altitude signatures. In the Pc1-2 (0.1-10 Hz) band wave-particle interaction in the equatorial region of the magnetosphere generates electromagnetic ion cyclotron (EMIC) wave packets which propagate down field lines to the ionosphere. These will be seen by NewMag in its polar orbit. ULF waves may be used as tracers in diagnostics.

CRCSS Space Science Research: 

CRCSS Space Science Research Space Weather Forecasting High energy magnetic cloud events outbursting from the Sun can impinge on the Earth and destroy satellites, disrupt power grid systems, HF radio communications and GPS navigation systems. These disruptions will maximise at the peak of the sunspot cycle when FedSat is expected to be operational. Continuous multipoint spacecraft measurements of the global magnetic field and plasma environment are required for early warning of impending events and inclusion in space weather prediction models. NewMag will make a contribution here. NEWMAG will provide near real-time data to the Space Environment Centre of NOAA in Boulder Colorado and the Ionospheric Prediction Service in Sydney.

CRCSS Space Science Research: 

CRCSS Space Science Research The Geomagnetic Field in the Australian Region The Australian Geological Survey Organisation (AGSO) provides reference and variability magnetic field data to the geophysical exploration/mining communities for mineral exploration. Since the geomagnetic field is continuously changing, the Australian Reference Field must be updated every few years. NewMag will provide input to this process. Spacecraft observations of sufficient accuracy have not been available for a number of years since MAGSAT in 1979-1980 and currently Oersted, Sunsat). NewMag star imager for precise altitude determination.

Slide17: 

The Earth’s Magnetosphere

Slide18: 

High Latitude Current Systems

Slide19: 

Field Aligned Current Identification

Slide20: 

Region 1, Region 2 Current Systems

Slide21: 

ULF Waves in the Magnetosphere

Slide22: 

Field Line Resonance Conjugacy

Slide23: 

The High Latitude Cusp Region after Glassmeier (1989)

NewMag Boom Deployment: 

NewMag Boom Deployment NewMag power on with boom stowed and data taken in order to obtain measure of background interference/noise. Boom released with NewMag taking data. Will later analyse to obtain boom deployment dynamics. Spectral analysis of Boom lock-in oscillations will provide information of the natural modes of the boom.

On-Orbit Commissioning: 

On-Orbit Commissioning Will take place at the commencement of on-orbit operations and before any other NewMag campaigns. Purpose is to characterise performance of the NewMag experiment and assess the effects of other payloads and platform systems. Systems will be cycled on and off one at a time where possible. ACS system, particularly Magnetorquers are critical. Star Camera commissioning.

NewMag Science Campaigns: 

NewMag Science Campaigns Low Data Rate (“Background”) Campaign This is routine operation of NewMag. Data are gathered at the low sample rate with the objective of developing as complete a dataset as possible. This will be in support of specific science projects for which a low data rate is suitable, and in support of such needs and projects (including major international programs) that will arise in the future. Dayside High Resolution Campaign The purpose of this campaign is to obtain high rate magnetometer data over the entire dayside hemisphere, for a specified number of orbits per day. Typically this may involve operating NewMag at the high data rate for 3 orbits centered around local noon. Periodic GPS time information will also be required.

NewMag Science Campaigns: 

NewMag Science Campaigns High Latitude Studies Campaign This is specifically to examine wave phenomena over the Arctic and Antarctic polar regions with high resolution. NewMag data will be analyzed in conjunction with data from suites of ground magnetometers operated by the Australian and New Zealand Antarctic Divisions and other international agencies. The campaign would typically involve NewMag operating at its high data rate whilst over the northern and/or southern polar regions for approximately 20% of 3 orbits per day. Equatorial Studies Campaign This is similar to the high latitude campaign except with the focus on the equatorial regions. Likely scientific collaborators include DSTO and IPS radio and Space Services. Typical operations may involve NewMag recording at its high data rate whilst over the equatorial regions for approximately 20% of 3 orbits per day. New

NewMag Science Campaigns: 

NewMag Science Campaigns Australian Sector Campaign This campaign involves operating with high data sample rates specifically over the Australian sector. This is in support of magnetic field modelling and mapping operations conducted by the Australian Geological Survey Organisation. Typical operations may involve NewMag recording at its high data rate between 0o and 60o latitude (approx. 17%) of 3 orbits/day. TIGER Campaign TIGER is a frequency agile HF radar and a component of the international SuperDARN consortium. It is situated in southern Tasmania and probes the ionosphere poleward of there. Opportunities exist for unique science projects involving TIGER, NewMag passes, and ground magnetometers. This work will involve collaborators at Antarctic Division, La Trobe University, and IPS Radio and Space Services. Operations may involve NewMag recording at its high data rate whilst over the southern ocean region for approximately 10% of 6 orbits per day.

Operating Schedules: 

Operating Schedules Low Data Rate (Background) Schedule This schedule is representative of routine operations at the low sample rate. NewMag recording data at 10 vector samples per second for all orbits per day. GPS receiver activated for UTC synchronization purposes at least twice per orbit. This will most likely be during the dayside part of each orbit. Assuming a 100-min orbit, typical GPS activation times could be 10 min after passing over the pole into the dayside hemisphere, and again 35 min into the orbit. NMCLK/OBET synchronization each 10 min. Star camera to be operating continuously throughout the orbit. Don’t care about the status of communications experiments, TT&C, HPCE, and reaction wheels.

Operating Schedules: 

Operating Schedules High Latitude Studies Schedule This schedule is typical of those involving a portion(s) of an orbit during which NewMag is operating at its high data rate mode. The campaign may typically involve NewMag operating at its high data rate whilst over the northern and southern daylit polar regions for ~20% of 3 orbits per day. All operations at low data rate schedule with following exceptions. NewMag logging data at 100 vector samples per second for 20% of three orbits per day, between approximately 60o and 78o latitude in both the northern and southern hemispheres, i.e. a total of 4 high data rate windows per orbit. The actual latitudes will vary (magnetic latitudes are of interest here) and will be specified in terms of OBET times. GPS receiver activated for UTC synchronization purposes TBA min before the start and TBA min after the end of each high data rate window. GPS need not be activated elsewhere during those orbits. Reaction wheel dumps not to take place during any part of the high sample rate windows.

Inter-Program Research: 

Inter-Program Research Inter-Program Projects: 1. The magnetometer experiment monitors the plasma environment surrounding FedSat and consequently will provide a reference for space weather effects that may produce upsets in the onboard electronics units, including the communications, navigation and computing systems payloads (Programs B and D) as well as the onboard platform housekeeping electronics. 2. The transfer of data recorded by remote ground based magnetometers may be accomplished through data transmission to FedSat using the UHF payload under Program B. This is currently being tested using the IRIDIUM satellite telephone network.

Slide35: 

ULF Plasma Waves

CRCSS Space Science Research: 

CRCSS Space Science Research Lower-band ELF Waves In the high latitude auroral region there are propagating wave modes generated in boundary/acceleration regions. These waves are controlled by the plasma H+, O+ and He+ cyclotron frequencies. At high latitudes and upper ionosphere altitudes the H+ cyclotron frequency is typically ~700Hz, the He+ ~200Hz, and the O+ ~40Hz. With an upper limit on the NewMag bandwidth of 50Hz it will only be possible to observe electromagnetic waves near and below the O+ frequency. Recent discovery of lightning discharges between the tops of clouds and the lower ionosphere, (red sprites & blue jets). FedSat will pass over the South-East Asian thunderstorm region, present between November and March.

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