Directly under the Arctic Circle! Marianne's Arctic Xpress in Tromsø offers fjord, whale and wildlife tours by day, aurora tours by night. Book Now and get a 10% discount on combo day and night adventures.
| || |
SUNSET SKY SHOW: When the sun goes down tonight, step outside and look west. An exquisitely slender crescent Moon is shining about 10 degrees to the right of Venus. A clear view of the horizon is essential, as both are hanging low. Sky maps: Oct. 2, Oct. 3.
SPRITES ABOVE HURRICANE MATTHEW: On Oct. 1st, Earth weather met space weather above Hurricane Matthew. As the giant storm system was approaching the Greater Antilles, Frankie Lucena of Puerto Rico photographed red sprites shooting up from the thunderclouds:
Sprites are a strange and beautiful form of lightning that shoot up from the tops of electrical storms. They reach all the way up to the edge of space alongside meteors, auroras, and noctilucent clouds. Some researchers believe cosmic rays help trigger sprites, making them a true space weather phenomenon.
Seeing sprites above a hurricane is rare. Most hurricanes don't even have regular lightning because the storms lack a key ingredient for electrical activity: vertical winds. (For more information read the Science@NASA article "Electric Hurricanes.") But Matthew is not a typical hurricane. It's one of the most powerful in recent years, briefly reaching Category 5 at about the time Lucena photographed the sprites. Perhaps extra-strong winds in the vicinity of the storm set the stage for upward-reaching bolts.
Sprite photographers across the Caribbean and the southeastern USA should be alert for more as the storm system approaches the mainland: observing tips.
Realtime Sprite Photo Gallery
NO SUNSPOTS. WHAT DOES IT MEAN? It's happening again: The sunspot number has dropped to zero. Yesterday, sunspot group AR2597 vanished, leaving the face of the sun blank. There are no significant dark cores in today's image of the sun from NASA's Solar Dynamics Observatory:
What does this mean? Blank suns herald the coming of Solar Minimum.
The sunspot cycle is like a pendulum, swinging back and forth with a period of 11 or 12 years. Right now the pendulum is swinging toward low sunspot numbers. Forecasters expect the the cycle to hit rock bottom in 2019-2020. Between now and then, there will be lots of spotless suns. At first, the blank stretches will be measured in days; later in weeks and months. The current blank spell is the 4th such interval of 2016, so far.
Because solar flares subside during Solar Minimum, many people think space weather goes away during this time. Not so. Solar Minimum brings many interesting changes. For instance, as the extreme ultraviolet output of the sun decreases, the upper atmosphere of Earth cools and collapses. This allows space junk to accumulate around our planet. Also, the heliosphere shrinks, bringing interstellar space closer to Earth. Galactic cosmic rays penetrate the inner solar system with relative ease. Indeed, there is already evidence of increasing radiation in Earth's atmosphere--a matter of keen interest to air travelers and possible space tourists.
Realtime Space Weather Photo Gallery
SPRINGTIME IN ANTARCTICA: Spring has begun in Antarctica, and the skies are turning green. No wonder overwintering researchers are taking off their parkas and going outside. B. Sudarsan Patro took this picture on October 1st from the Bharati Indian Base Station in the Larsemann Hills:
"The view was absolutely amazing,"says Patro. "The auroras were so bright and colorful. They brought joy to our celebration of Navaratri."
Navaratri is a festival dedicated to the worship of the Hindu deity Durga. Technically, it begins on Oct. 2nd, but Patro and colleagues got an early start. The festival lasts 9 days. Earth is passing through an unusually broad stream of solar wind, so a fair fraction of the celebration could be attended by Southern Lights.
As October begins, the solar wind around Earth is blowing almost 600 km/s (1.3 million mph). This could spark auroras around both poles this weekend. Monitor the gallery for sightings:
Realtime Aurora Photo Gallery
| ||Cosmic Rays in the Atmosphere |
Updated: Sept. 29 2016 // Next Flight: Oct. 1, 2016
Sept. 20, 2016: Readers, thank you for your patience while we continue to develop this new section of Spaceweather.com. We've been working to streamline our data reduction, allowing us to post results from balloon flights much more rapidly, and we have developed a new data product, shown here:
This plot displays radiation measurements not only in the stratosphere, but also at aviation altitudes. Dose rates are expessed as multiples of sea level. For instance, we see that boarding a plane that flies at 25,000 feet exposes passengers to dose rates ~10x higher than sea level. At 40,000 feet, the multiplier is closer to 50x. These measurements are made by our usual cosmic ray payload as it passes through aviation altitudes en route to the stratosphere over California.
What is this all about? 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. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias and sudden cardiac death in the general population. Our latest measurements show that cosmic rays are intensifying, with an increase of more than 12% since 2015:
Why are cosmic rays intensifying? The main reason is the sun. Solar storm clouds such as coronal mass ejections (CMEs) sweep aside cosmic rays when they pass by Earth. During Solar Maximum, CMEs are abundant and cosmic rays are held at bay. Now, however, the solar cycle is swinging toward Solar Minimum, allowing cosmic rays to return. Another reason could be the weakening of Earth's magnetic field, which helps protect us from deep-space radiation.
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 data points in the graph above correspond to the peak of the Reneger-Pfotzer maximum, which lies about 67,000 feet above central California. When cosmic rays crash into Earth's atmosphere, they produce a spray of secondary particles that is most intense at the entrance to the stratosphere. Physicists Eric Reneger and Georg Pfotzer discovered the maximum using balloons in the 1930s and it is what we are measuring today.
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 Oct. 2, 2016, the network reported 22 fireballs.
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 October 2, 2016 there were 1731 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.
| ||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 |
| ||a proud supporter of science education and Spaceweather.com |
| ||the underlying science of space weather |
| ||Find homes for sale in Ocala, Orlando and Tampa with the #1 real estate company in Central Florida Local Realty Service |
| ||Visit Need An Eitzah for all your questions and forum discussions on Jewish life. |
| ||These links help Spaceweather.com stay online. Thank you to our supporters! |