SWP Cheat Sheet 2026

The 30 highest-yield SWP facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which geographic characteristic makes a region's power grid most susceptible to GIC damage? → High latitude with resistive igneous bedrock and long transmission lines
2. Which region of the atmosphere is directly affected during ionospheric storms? → Ionosphere
3. The Starfish Prime nuclear test in 1962 is notable in space weather history because it: → Created an artificial radiation belt that damaged multiple satellites
4. The NOAA S-scale for solar radiation storms is defined using the flux of protons with energies exceeding which threshold? → 10 MeV (S1 begins at 10 pfu)
5. Which ground-based network provides the primary global real-time geomagnetic index data used by SWPC for operational Kp forecasting? → INTERMAGNET global network of digital magnetic observatories
6. The GOES X-ray Sensor (XRS) monitors solar X-rays in which two channels used to classify flares? → 0.1–0.8 nm (long) and 0.05–0.4 nm (short)
7. Which space weather phenomenon is most responsible for increased satellite drag in low Earth orbit? → Solar EUV heating of the upper atmosphere
8. The March 1989 geomagnetic storm famously caused: → Collapse of the Hydro-Québec power grid in approximately 92 seconds
9. How can geomagnetic storms affect satellite operations? → They can disrupt electronics and cause orbit drift
10. Total Electron Content (TEC) maps of the ionosphere are derived primarily from: → Dual-frequency GPS/GNSS receiver networks measuring signal delay differences
11. A 'magnetic cloud' is a subset of CMEs identified by: → Smoothly rotating magnetic field, low proton temperature, and low plasma beta
12. Which instrument suite serves as the primary real-time monitor of solar energetic particles used in operational NOAA space weather forecasting? → GOES Energetic Particle Sensor (EPS) and High Energy Proton and Alpha Detector (HEPAD)
13. GPS receivers correct for ionospheric signal delay using: → A single-frequency Klobuchar model or dual-frequency differential measurements
14. WWVB and other standard time/frequency broadcasts use LF/MF frequencies which are affected by space weather through: → Solar flare X-rays causing sudden phase anomalies in the D-region waveguide
15. Which solar event type is most commonly associated with the largest solar energetic particle (SEP) events? → Fast coronal mass ejections driving interplanetary shocks (gradual SEP events)
16. The transit time of a CME from the Sun to Earth at 1 AU typically ranges from: → 1–3 days
17. The 'slot region' between the inner and outer Van Allen belts remains relatively depleted of energetic electrons because of: → Efficient pitch angle scattering by plasmaspheric hiss at those L-shell values
18. What triggers a geomagnetic storm? → Solar wind disturbances from CMEs
19. A 'radio blackout watch' issued by SWPC is triggered when: → Active regions on the solar disk have potential for significant flare activity
20. GIC neutral blocking devices protect transformers by: → Inserting capacitors in the neutral-to-ground connection to block DC while passing AC
21. Solar panel degradation on satellites is primarily caused by which space weather component? → High-energy trapped electrons and protons
22. Where does the ring current form during geomagnetic activity? → In the inner magnetosphere
23. SOHO's LASCO coronagraph is primarily used in space weather operations to: → Detect and characterize coronal mass ejections from solar disk imagery
24. Which spacecraft first directly measured the local interstellar cosmic ray spectrum, confirming the extrasolar origin of GCRs? → Voyager 1 and Voyager 2 after crossing the heliopause
25. Approximately how long does it take for ~10 MeV solar energetic protons to travel from the Sun to Earth along the Parker spiral magnetic field? → 1–2 hours along the ~1.2 AU field line path
26. Which parameter is most useful for assessing satellite charging risk at geostationary orbit? → Energetic electron flux at >2 MeV
27. The Maximum Usable Frequency (MUF) for HF skywave propagation is directly determined by: → The critical frequency (foF2) of the ionospheric F2 layer
28. At 1 AU, the average solar wind speed is approximately: → 400–500 km/s
29. The Van Allen radiation belts are composed primarily of which particles? → Energetic electrons and protons trapped by Earth's dipole magnetic field
30. What is the D-layer of the ionosphere primarily responsible for? → Absorbing high-frequency radio waves