On May 9th, the planet Mercury will pass in front of the sun, producing an inky-black spot on the solar disk. Catch it live on the Internet, courtesy of the Coca-Cola Space Science Center in Columbus, Georgia.
| || |
TRANSIT OF MERCURY: Today, May 9th, Mercury passed directly between Earth and the sun, producing a rare transit of Mercury's inky-black disk across the solar surface. Images of the event are pouring into our image gallery from around the world. Browse and enjoy!
STRONG GEOMAGNETIC STORM: For the past 24+ hours, Earth's magnetic field has been reverberating with geomagnetic storms. At their most intense on May 8th, G3-class storms sparked bright auroras around both poles, parts of four continents, and more than a half a dozen US states. In Antarctica, everything turned green:
"The auroras were beautiful at Argentina's Belgrano II base in Antarctica," reports photographer Gabriel Saiquita, who has witnessed bright Southern Lights for two days in a row.
In the United States, auroras were sighted in Alaska, Washington, Idaho, Michigan, Montana, Minnesota, and even Arkansas.
The "Mother's Day Storms" of May 8th began when Earth crossed a fold in the heliospheric current sheet, entering a region of space filled with negative-polarity magnetic fields. Such fields easily link to Earth's magnetic field, opening a crack in our planet's magnetosphere. Solar wind pours in to fuel spectacular auroras.
Overall, this was the strongest episode of geomagnetic activity so far in 2016. The storms are subsiding now. NOAA forecasters estimate a 65% chance of minor G1-class storms on May 9th as Earth's magnetic environment returns to normal. Aurora alerts: text, voice.
Realtime Aurora Photo Gallery
DOUBLE SPACE WEATHER BALLOON LAUNCH: Yesterday, May 8th, Spaceweather.com and the students of Earth to Sky Calculus conducted a double-launch of space weather balloons. The two balloons, one released from Oregon and the other from California, flew into the strongest geomagnetic storm of 2016.
Each of the balloons carried a cosmic ray payload to the stratosphere, measuring atmospheric radiation from ground level to the edge of space during the G3-class storm. What effect does such a strong geomagnetic storm have on the upper atmosphere? And does Oregon receive more space radiation because of its higher magnetic latitude? These are just two of the questions we hope to answer.
The payloads have since parachuted back to Earth--one landing in the foothills of the Sierra Nevada mountains of California, and the other on the east side of the Cascade mountains near Bend, Oregon. Recovery teams will enter the wilderness on May 9th and bring back the data. Stay tuned!
Realtime Space Weather Photo Gallery
Realtime Sprite Photo Gallery
Realtime Comet Photo Gallery
Every night, a network of NASA all-sky cameras
scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics. Daily results are presented here on Spaceweather.com.
On May. 9, 2016, the network reported 9 fireballs.
(5 sporadics, 3 eta Lyrids, 1 eta Aquariid)
In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue). [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.
On May 9, 2016 there were 1701 potentially hazardous asteroids. Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.
| ||Cosmic Rays in the Atmosphere |
These measurements are based on regular space weather balloon flights: learn more.
|Situation Report -- Oct. 30, 2015 ||Stratospheric Radiation (+37o N) |
|Cosmic ray levels are elevated (+6.1% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month. |
|Sept. 06: 4.14 uSv/hr (414 uRad/hr) |
|Sept. 12: 4.09 uSv/hr (409 uRad/hr) |
|Sept. 23: 4.12 uSv/hr (412 uRad/hr) |
|Sept. 25: 4.16 uSv/hr (416 uRad/hr) |
|Sept. 27: 4.13 uSv/hr (413 uRad/hr) |
|Oct. 11: 4.02 uSv/hr (402 uRad/hr) |
|Oct. 22: 4.11 uSv/hr (411 uRad/hr) |
Approximately once a week, Spaceweather.com and the students of Earth to Sky Calculus fly "space weather balloons" to the stratosphere over California. These balloons are equipped with radiation sensors that detect cosmic rays, a surprisingly "down to Earth" form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. For example, here is the data from a flight on Oct. 22, 2015:
Radiation levels peak at the entrance to the stratosphere in a broad region called the "Pfotzer Maximum." This peak is named after physicist George Pfotzer who discovered it using balloons and Geiger tubes in the 1930s. Radiation levels there are more than 80x sea level.
Note that the bottom of the Pfotzer Maximim is near 55,000 ft. This means that some high-flying aircraft are not far from the zone of maximum radiation. Indeed, according to the Oct 22th measurements, a plane flying at 45,000 feet is exposed to 2.79 uSv/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in about 5 hours.
The radiation sensors onboard our helium balloons detect X-rays and gamma-rays in the energy range 10 keV to 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.
| ||The official U.S. government space weather bureau |
| ||The first place to look for information about sundogs, pillars, rainbows and related phenomena. |
| ||Researchers call it a "Hubble for the sun." SDO is the most advanced solar observatory ever. |
| ||3D views of the sun from NASA's Solar and Terrestrial Relations Observatory |
| ||Realtime and archival images of the Sun from SOHO. |
| ||from the NOAA Space Environment Center |
| ||the underlying science of space weather |