[Larger image] [movies] Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU.None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time.Paleomagnetic data from a piston core off the East Cape, North Island, New Zealand, reveal a continuous record of the earth’s magnetic field for the last ca. This record is used to constrain the age of the Matakaoa Debris Avalanche.The pattern of geomagnetic reversals, geomagnetic excursions, the relative paleointensity and the magnetic susceptibility were obtained from the “MD06-3010” core, acquired by the French RV Marion Dufresne.My antennas have always been simple (and often indoors!) and I prefer to use low power levels to make my contacts.The comparison of the pattern of the relative paleointensity contributes to the age determination of the MD06-3010 core.The Matakaoa Debris Avalanche is shown to predate 200 ka and an age older than the Mamaku Ignimbrite (ca.
Visit Explore the Arctic Any night this week, step outside after midnight and look south. NOAA forecasters say there is a 60% chance of G1-class geomagnetic storms on June 1st when a solar wind stream is expected to hit Earth's magnetic field.
"We spotted the first hint of NLCs in our data on May 23rd; now they are brightening rapidly." NLCs are Earth's highest clouds.
Seeded by meteoroids, they float at the edge of space more than 80 km above the planet's surface.
I have been into radio since I was about 7 years old, and a transmitting radio ham since the age of 14 (1982).
In this time I have worked or heard most of the 340 or so countries/entities in the world and have well over 200 DXCC entities confirmed.