Space Weather Update: 05/05/2016
By Spaceweather.com, 05/05/2016
METEORS FROM HALLEY’S COMET: Earth is entering a stream of debris from Halley’s Comet, source of the annual eta Aquariid meteor shower. Forecasters expect the shower to peak on the nights around May 5th and 6th with 30+ meteors per hour. The best time to look, no matter where you live, is probably during the dark hours before sunrise on Friday. Got clouds? No problem. You can still experience this meteor shower by listening to it. Meteor radar echoes are being streamed live on Space Weather Radio.
RETURN OF THE HEART-SHAPED SUNSPOT: Last month, heart-shaped sunspot AR2529 unleashed the strongest solar flare of 2016 (category M6.7). Guess what? It’s back. The active region is emerging over the sun’s eastern limb following a two-week trip around the farside of the sun:
Back in April, observers marveled at the romantic shape of AR2529. Since then, it has decayed. The sunspot no longer resembles a heart, and its weakened magnetic field poses a waning threat for explosions. NOAA forecasters estimate a scant 5% chance of M-class flares on May 5th.
According to tradition, sunspots that circle around the farside of the sun are re-numbered when they return. The new designation of AR2529 is AR2542, and that is how we will refer to it from now on. Readers with backyard solar telescopes are encouraged to monitor AR2542 as it (re-)turns toward Earth.
SPHERICAL CAMERA AT THE EDGE OF SPACE: On May 1st, Spaceweather.com and students of Earth to Sky Calculus launched another space weather balloon to the stratosphere. Onboard was a spherical 360o camera. We’ve flown this camera before, but this time we flew it upside down. This arrangement afforded a better view of Earth’s surface, unobstructed by a thermal pack which keeps the camera warm at the frigid edge of space. Here are the results:
The interactive image can be spun around and zoomed. Be sure to zoom in on the tiny red box; that’s the payload capsule suspended 109,000 feet above Earth’s surface. Inside the capsule is an array of X-ray/gamma-ray sensors for monitoring cosmic rays. Regular space weather balloon launches since 2014 have shown thatcosmic radiation is intensifying–a trend we are monitoring closely. Spherical images are just icing on the cake of this important scientific research.
Bonus: The spherical camera also captured an interesting image en route to the stratosphere. This one shows virga (rain that evaporates before it hits the ground) over Crowley Lake, CA:
As before, click on the interactive image, then spin it around for the complete spherical experience.
“SPACE LIGHTNING” OVER THE CARIBBEAN: Sprite season is definitely underway. Only a few days after a widespread display appeared over Texas, more sprites have popped up near Puerto Rico. Frankie Lucena photographed them on May 1st from Cabo Rojo:
“They appeared right beside Mars and Saturn in the constellation Scorpius,” says Lucena. “The sprites were over the Caribbean Sea just south of Cabo Rojo.”
Sprites are an exotic form of upper atmospheric electricity, sometimes called “space lightning” because they reach altitudes associated with meteors, noctilucent clouds and auroras. Some researchers believe they are linked to cosmic rays: Subatomic particles from deep space striking the top of Earth’s atmosphere produce secondary electrons that, in turn, could provide the spark that triggers sprites.
Lucena’s ocean-going sprites are somewhat unusual. “A satellite study by Chen et al. 2008 (JGR) showed 49% of sprites to occur over land, 28% over the ocean and the remaining ones near the coastlines,” explains lightning scientist Oscar van der Velde of the Technical University of Catalonia, Spain. “As oceans cover a greater area, this indicates sprites are more common over land-based storms.”
Although sprites have been seen for at least a century, most scientists did not believe they existed until after 1989 when sprites were photographed by cameras onboard the space shuttle. Now “sprite chasers” routinely photograph sprites from their own homes. “They are easily detected by certain cameras,” says van der Velde, “and if a storm is in the mood, you may record one every few minutes.” Give it a try!
All Sky Fireball Network
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. 5, 2016, the network reported 22 fireballs.
(12 eta Aquariids, 10 sporadics)
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]
Near Earth Asteroids
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 5, 2016 there were 1698 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:Asteroid
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
Situation Report — Oct. 30, 2015Stratospheric 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)
These measurements are based on regular space weather balloon flights: learn more.
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.
speed: 377.3 km/sec
density: 5.3 protons/cm3
explanation | more data
Updated: Today at 1739 UTX-ray Solar Flares
6-hr max: B3 1426 UT May05
24-hr: B4 0726 UT May05
explanation | more data
Updated: Today at: 1700 UTDaily Sun: 05 May 16New sunspot AR2542 is actually an old friend. It is the sunspot formerly known as “AR2529” returning from a two week trip around the far side of the sun. Credit: SDO/HMI
Sunspot number: 67
What is the sunspot number?
Updated 05 May 2016
Current Stretch: 0 days
2016 total: 0 days (0%)
2015 total: 0 days (0%)
2014 total: 1 day (<1%)
2013 total: 0 days (0%)
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)
Updated 05 May 2016
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/OvationPlanetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 3 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 6.9 nT
Bz: 3.7 nT north
explanation | more data
Updated: Today at 1739 UTCoronal Holes: 05 May 16Solar wind flowing from the indicated coronal hole could reach Earth on or about May 7th. Credit: SDO/AIA.Noctilucent Clouds The southern season for noctilucent clouds has ended and we are now waiting for the first northern NLCs to appear–probably in mid-to late-May.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, PolarUpdated at: 02-12-2016 16:55:02
Updated at: 2016 May 04 2200 UTC
Probabilities for significant disturbances in Earth’s magnetic field are given for three activity levels: active, minor storm, severe stormUpdated at: 2016 May 04 2200 UTCMid-latitudes