RECENT IONOSPHERE COLLECTION RESULTS FROM A 3U CUBESAT GNSS-RO - - PowerPoint PPT Presentation

RECENT IONOSPHERE COLLECTION RESULTS FROM A 3U CUBESAT GNSS-RO CONSTELLATION

Timothy M Duly1, Dave Ector1, Vladimir Irisov1, Vu Nguyen1, Oleguer Nogués-Correig2, Linus Tan3, and Takayuki Yuasa3

1 Spire Global, Inc, Boulder, Colorado, United States 2 Spire Global, Inc, Glasgow, United Kingdom 3 Spire Global, Inc, Singapore

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January 8, 2018 02:45 PM - 03:00 PM AMS 2018 Observational Platforms for Space Weather - Part II

SPIRE GLOBAL, INC.

• Building the most advanced,

constantly refreshed 3U CubeSat

• 50+ CubeSats launched
• Manufacturing up to 2 satellites

per week

• 4 months from design to launch
• 26+ ground stations globally

ensures low latency

• Provide rapidly refreshed data:

AIS, ADS-B (soon), and GNSS Radio Occultation (RO)

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RADIO OCCULTATION (RO)

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Earth LEO GPS α

p p

Atmosphere Ionosphere

GPS Sats for POD

RO is a robust and highly accurate technique for the remote sensing of Earth's neutral and plasma atmosphere Comparison against the Global Forecast System (GFS) numerical weather model

See talk: "6A.1: Atmospheric Radio Occultation Observation from Spire CubeSat Nanosatellites" by V. Irisov on Thurs, Jan 11 at 1:30pm in the "Atmospheric Soundings from Satellites" Session, Room 19AB (ACC)

REMOTE SENSING THE IONOSPHERE

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• Dual frequency GNSS receiver is

also capable of ionospheric remote sensing

• Total electron content (TEC) from
• verhead GNSS links
• Scintillation indices (S4 and σΦ)
• [future] Ionospheric occultations →

electron density profiles Access to RO data (both neutral and plasma) are available via Spire's RO API (requires authentication) Receive "POD TEC" data from multiple dual frequency GNSS links

REMOTE SENSING THE IONOSPHERE

5 LEO track approximates ionospheric sampling region

(Bias corrected) TEC generally follows IRI, an ionospheric climatological model

Note: 1 TEC "Unit" (TECU) = 1016 electrons/m2

EXAMPLE COVERAGE (~3 HOURS)

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~2 orbits provide diverse, global coverage

• f ionospheric region

from one CubeSat Again, LEO track approximates ionospheric sampling region

THE GREAT AMERICAN SOLAR ECLIPSE

7 approx eclipse path

Decrease in TEC due to Eclipse? Constantly refreshed, global coverage provides unique

• pportunity to investigate

ionospheric events

SPORADIC E LAYERS

• Occultation data may

also measure ionospheric Sporadic E layers

• Observations of △TEC

and SNR fluctuations at ~110 km, indicative of Es

• Similar to published data

from GPS-CHAMP

8 Wu et al (2005), Sporadic E morphology from GPS-CHAMP radio occultation, JGR (link) (signal strength)

OCCULTATION LOCATIONS

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With slight adjustments to firmware and ground processing, these locations could also represent electron density profiles Locations of RO atmospheric profiles

BY THE NUMBERS: DECEMBER 2017

• RO Ground Processing team

maintains an extensive database of processing results (both RO profiles and ionospheric results)

• December 2017 saw ramp up in

RO Production

• Mainly from ~3 hour daily

collections from 1 or 2 CubeSats

• Continue steadily increasing

production numbers in 2018, (e.g., 500 profiles/day in Jan.)

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December 2017 Number of TEC data points 3,136,691 Number of TEC "arcs" 2,122 Number of scintillation data points 78,246

OUTLOOK

• Spire is building a large (>100)

constellation of satellites to collect atmospheric and ionospheric data using RO for weather and space weather forecasting improvements

• Advance ionosphere processing:

electron density profiles, Sporadic E layers, etc.

• Upcoming:
• 6 months: 3,000 profiles/day
• 12 months: 8,000 profiles/day

11 Spire CubeSats awaiting deployment from the Cygnus resupply module (Credit: NASA Astronaut Randy Bresnik, @AstroKomrade)

More info: https://spire.com/data/weather/

For any questions, please contact:

1050 Walnut, Suite 402, Boulder, CO 80302 USA

Timothy M. Duly

timothy.duly@spire.com

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