Marianne’s Arctic tours: Operating in small groups of 7 to 14 persons--all needs supplied for safety, comfort and pleasure. Night & day photography or non-photographic landscape - wildlife tours. Click for details! | | |
MINOR SOLAR WIND STREAM: An equatorial hole in the sun's atmosphere is facing Earth, and it is spewing a minor stream of solar wind in our direction, Estimated time of arrival: Feb. 15-16. The gaseous material is not expected to cause a geomagnetic storm. Nevertheless, Arctic sky watchers can expect an uptick in polar auroras. Aurora alerts: SMS Text.
SURFING THE JET STREAM REDUCES AVIATION RADIATION: Climate change is revving up the jet stream. The river of air which meanders around the North Pole is quickening, propelling planes across the north Atlantic at record speed. Just this weekend, on Feb. 8th, British Airways Flight 112 rocketed from New York to London in 4 hours 56 minutes, at one point traveling faster than 825 mph.
Why do we care? Because airplanes surfing the jet stream absorb significantly less cosmic radiation.
(Top)The flight path of British Airways 112 and (Bottom) the transatlantic jet stream on Feb. 8, 2020. Credit: FlightRadar24.com
Researchers have long known that air travelers are exposed to cosmic rays. At typical cruising altitudes, passengers absorb 50 to 100 times more radiation than they would at sea level. This has led the International Commission on Radiological Protection (ICRP) to classify pilots and flight attendants as occupational radiation workers.
By shortening flights, the jet stream reduces exposure to cosmic rays. Passengers onboard the record-setting British Airways flight spent an hour less at cruising altitude and, according to our models, absorbed about 30% less radiation. Two Virgin Atlantic flights following close on the heels of the British Airways 747 had similar results.
These conclusions are based on E-RAD, a new model for aviation radiation. Since 2015, we (Spaceweather.com and the students of Earth to Sky Calculus) have been collecting X-ray, gamma-ray, and neutron radiation data onboard airplanes. Our database contains more than 25,000 radiation measurements over 27 countries, 5 continents, and 2 oceans. E-RAD uses these measurements to predict dose rates on flights in regions of the world we have visited, such as the north Atlantic.
We applied E-RAD to British Airways Flight 112 on several dates, comparing dosages on Feb. 8th, when the plane surfed the jet stream, to nearby dates when it didn’t. Surfing the jet stream shaved 6 to 10 uSv (microSeiverts) off the total radiation dose, a reduction equivalent to ~1 dental X-ray.
It’s not all good news, though. The jet stream can cause trouble. An active, fast-moving jet stream is often filled with turbulence, making flights miserable for passengers. Planes dodging the rough air can actually increase their flight times, boosting cosmic ray exposure instead of reducing it.
Oh, and did you want to go home? Passengers returning to New York from London have to cross the Atlantic against the jet stream. Their flights will be slower, increasing exposure-time. Indeed, we calculated the radiation exposure for British Airways Flight 117 on Feb 8th, which flew in the opposite direction, from London to New York. Passengers onboard that aircraft would have received double the dosage–34.4 uSv (London to New York) instead of 17.7 uSv (New York to London).
Climate change research suggests that all of these effects will intensify in the years ahead. A seminal study in 2016 found that, overall, changes in atmospheric dynamics would increase round-trip times between London and New York despite the quickening jet stream. In the end, it seems, you just can’t avoid "rads on a plane."
A sharable version of this story is available here.
Realtime Spaceweather Photo Gallery
Free: Spaceweather.com Newsletter
VALENTINE'S GIFTS FROM THE EDGE OF SPACE: Valentine's Day is less than a week away. Nothing says "I love you" like a gift from the edge of space. Everything in the Earth to Sky Store is 10% off from now until Feb. 14th:
Everything in the store has been flown to the stratosphere onboard cosmic ray balloons, which the students of Earth to Sky Calculus launch approximately once a week to monitor atmospheric radiation. All sales support our cosmic ray ballooning program and help launch young scientists into research careers through hands-on STEM education.
At checkout, be sure to enter the coupon code "ILOVESPACE"!
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
A METEOR STORM IN SPACE? Spoiler alert: It's not a meteor storm. Earlier today, coronagraphs onboard the Solar and Heliospheric Observatory (SOHO) were staring at the sun, waiting for the next coronal mass ejection, when a flurry of objects streaked across the field of view. This animation shows what happened:
The starry background was briefly overwhelmed by smears of light, as if a stream of debris had engulfed the spacecraft. In fact, the "meteor storm" may have come from the spacecraft itself.
Ever since SOHO was launched in 1995, coronagraph images have occasionally recorded streaks of light. Mission controllers believe they are bits of insulation flaking off the sun-facing side of the spacecraft, reflecting sunlight as they race out-of-focus in front of the coronagraph's digital camera.
Today's event was more dramatic than most. Indeed, a meteoroid might have been involved. A micrometeoroid strike might have dislodged a spray of insulation, resulting in not one but dozens of luminous streaks. Whatever happened, it didn't harm the spacecraft. SOHO is still operating normally.
Realtime Spaceweather Photo Gallery
Free: Spaceweather.com Newsletter
Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter
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 Feb. 12, 2020, the network reported 1 fireball.
(1 sporadic)
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 February 12, 2020 there were 2018 potentially hazardous asteroids.
|
Recent & Upcoming Earth-asteroid encounters: Asteroid | Date(UT) | Miss Distance | Velocity (km/s) | Diameter (m) |
2020 BF11 | 2020-Feb-07 | 16.8 LD | 13.9 | 35 |
2020 BL8 | 2020-Feb-08 | 6.6 LD | 3.2 | 25 |
2020 BQ11 | 2020-Feb-08 | 14.1 LD | 21.3 | 46 |
2020 BW5 | 2020-Feb-09 | 5.2 LD | 9 | 19 |
2020 BK10 | 2020-Feb-10 | 1.9 LD | 11.5 | 21 |
2020 CY1 | 2020-Feb-10 | 5.9 LD | 40.2 | 66 |
2020 BC10 | 2020-Feb-10 | 15.2 LD | 7.6 | 33 |
2020 CH | 2020-Feb-12 | 11.6 LD | 9.4 | 31 |
2020 CF | 2020-Feb-12 | 14.8 LD | 5.3 | 12 |
163373 | 2020-Feb-15 | 15.1 LD | 15.2 | 589 |
2020 BL14 | 2020-Feb-16 | 18 LD | 8.8 | 33 |
2020 CK1 | 2020-Feb-17 | 8.6 LD | 8.1 | 16 |
2018 CW2 | 2020-Feb-17 | 6 LD | 10.2 | 28 |
2020 BA10 | 2020-Feb-18 | 12.3 LD | 9 | 28 |
2020 CX1 | 2020-Feb-19 | 14.1 LD | 7.9 | 53 |
2020 BL7 | 2020-Feb-19 | 13.9 LD | 8.5 | 36 |
2020 BC9 | 2020-Feb-20 | 13.9 LD | 9.3 | 77 |
2019 BE5 | 2020-Feb-20 | 13.7 LD | 14.8 | 34 |
2011 DR | 2020-Feb-23 | 14.7 LD | 5.8 | 25 |
2016 CO246 | 2020-Feb-23 | 18.4 LD | 5.9 | 25 |
2020 BR10 | 2020-Feb-23 | 15.4 LD | 15.1 | 101 |
2020 BW13 | 2020-Feb-24 | 9.1 LD | 2.4 | 12 |
2012 DS30 | 2020-Feb-26 | 12.3 LD | 5.4 | 22 |
2015 BK509 | 2020-Feb-29 | 18.7 LD | 12.5 | 118 |
2017 BM123 | 2020-Mar-01 | 10.5 LD | 8.1 | 65 |
2018 RF6 | 2020-Mar-10 | 11.2 LD | 12.6 | 36 |
2008 UB95 | 2020-Mar-11 | 18.5 LD | 7.6 | 41 |
2018 GY | 2020-Mar-15 | 6.2 LD | 9.5 | 39 |
2012 XA133 | 2020-Mar-27 | 17.4 LD | 23.7 | 235 |
2010 GD35 | 2020-Mar-29 | 15.3 LD | 12 | 43 |
2006 FH36 | 2020-Mar-30 | 11.3 LD | 5.1 | 93 |
2019 GM1 | 2020-Apr-02 | 9 LD | 4.2 | 14 |
2015 FC35 | 2020-Apr-04 | 10.4 LD | 13.8 | 148 |
2019 HM | 2020-Apr-10 | 7.2 LD | 3.2 | 23 |
363599 | 2020-Apr-11 | 19.2 LD | 24.5 | 224 |
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 |
SOMETHING NEW! We have developed a new predictive model of aviation radiation. It's called E-RAD--short for Empirical RADiation model. We are constantly flying radiation sensors onboard airplanes over the US and and around the world, so far collecting more than 22,000 gps-tagged radiation measurements. Using this unique dataset, we can predict the dosage on any flight over the USA with an error no worse than 15%.
E-RAD lets us do something new: Every day we monitor approximately 1400 flights criss-crossing the 10 busiest routes in the continental USA. Typically, this includes more than 80,000 passengers per day. E-RAD calculates the radiation exposure for every single flight.
The Hot Flights Table is a daily summary of these calculations. It shows the 5 charter flights with the highest dose rates; the 5 commercial flights with the highest dose rates; 5 commercial flights with near-average dose rates; and the 5 commercial flights with the lowest dose rates. Passengers typically experience dose rates that are 20 to 70 times higher than natural radiation at sea level.
To measure radiation on airplanes, we use the same sensors we fly to the stratosphere onboard Earth to Sky Calculus cosmic ray balloons: neutron bubble chambers and X-ray/gamma-ray Geiger tubes sensitive to energies between 10 keV and 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.
Column definitions: (1) The flight number; (2) The maximum dose rate during the flight, expressed in units of natural radiation at sea level; (3) The maximum altitude of the plane in feet above sea level; (4) Departure city; (5) Arrival city; (6) Duration of the flight.
SPACE WEATHER BALLOON DATA: 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 18% since 2015:
The data points in the graph above correspond to the peak of the Regener-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.
En route to the stratosphere, our sensors also pass through aviation altitudes:
In this plot, 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.
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.
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 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 |
| fun to read, but should be taken with a grain of salt! Forecasts looking ahead more than a few days are often wrong. |
| from the NOAA Space Environment Center |
| the underlying science of space weather |
| To find reviews of new online casino sites in the UK try The Casino DB where there are hundreds of online casino reviews complete with bonuses and ratings. Get a bonus when playing at a new casino in the UK. The Genie got you covered! Looking for a new online casino? Try Casimpo the new site dedicated to making online casino simple and easy for all. |
| These links help Spaceweather.com stay online. Thank you to our supporters! |
| | | | | |