Lights Over lapland is excited to announce that Autumn Aurora Adventures are available for immediate booking! Reserve your adventure of a lifetime in Abisko National Park, Sweden today! | | |
SOLAR WIND STREAM APPROACHES EARTH: A high-speed stream of solar wind is approaching Earth. Estimated time of arrival: July 8th or 9th. Minor G1-class geomagnetic storms are possible during the weekend ahead when the solar wind makes first contact with Earth's magnetic field. Bright moonlight will interfere with the visibility of auroras. Free: Aurora Alerts
SUNSPOTS ARE VANISHING: Today, July 5th, the sun is blank--no sunspots. White light images from NASA's Solar Dynamics Observatory show no dark cores anywhere on the solar disk:
This marks the 44th day in 2017 without sunspots. So many blank suns is a clear sign that Solar Minimum is approaching. The last time the solar cycle shifted in this way, ~10 years ago, the sun plunged into the deepest Solar Minimum in a century. Between 2008 and 2009, sunspots were absent almost all the time; cosmic rays from deep space penetrated the solar system in record numbers; and Earth's upper atmosphere collapsed. We are on the verge of this happening again.
Yesterday, July 4th, at a meeting in the UK, researchers led by Prof. Yvonne Elsworth at the University of Birmingham reported that acoustic waves inside the sun shifted frequencies during the previous Solar Minimum (2008-2009), and those frequency shifts have persisted to the present day. "This lends weight to speculation that a fundamental change in the nature of the [sun's magnetic] dynamo may be in progress," they stated in a paper recently published in the Monthly Notices of the Royal Astronomical Society. These findings suggest that another deep Solar Minimum could be in the offing. Stay tuned for more blank suns.
THESE PENDANTS HAVE TOUCHED SPACE: Looking for a far-out gift? On April 15, 2017, the students of Earth to Sky Calculus flew a payload-full of heart-shaped Venus pendants to the stratosphere onboard a high-altitude helium balloon. Here's one floating 111,550 feet above the Sierras of central California:
You can have one for $129.95. Each glittering pendant comes with a greeting card showing the jewelry in flight and telling the story of its journey to the stratosphere and back again.
More items from the edge of space may be found in the Earth to Sky Store. All proceeds support atmospheric radiation monitoring and hands-on STEM education.
Far Out Gifts: Earth to Sky Store
All proceeds support hands-on STEM education
NOCTILUCENT CLOUD ACTIVITY: Nightfall is supposed to bring darkness. This week in parts of Europe, nightfall has brought something different: Bright ripples of electric-blue. "Wow, I witnessed an absolutely spectacular display of noctilucent clouds on July 3rd," says Ruslan Merzlyakov, who sends this self-portrait from Nykøbing Mors, Denmark:
""The whole sky was filled with the shining silver, stretching from west to east and even right above my head!" he adds. "The display lasted so long, I had plenty of time to make a video of it."
This and other outbreaks like it are telling us something about the weather in Earth's mesosphere: It's very cold up there. Noctilucent clouds form when summertime wisps of water vapor rise to the top of the atmosphere, coating specks of meteor smoke with fragile crystals of ice. This process requires temperatures as low as 145 K (-128 C). In early June, an unexpected heat wave in the mesosphere temporarily wiped out noctilucent clouds. Their return proves that the heat wave is over.
Noctilucent clouds are usually confined to near-Arctic latitudes. In recent years, however, they have been sighted as far south as Utah and Kansas in the United States. The ongoing apparition in Europe could herald such a widespread display in the nights ahead. Observing tips: Look west 30 to 60 minutes after sunset when the sun has dipped ~10 degrees below the horizon. If you see blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud: diagram.
Realtime Noctilucent Cloud Photo Gallery
NOCTILUCENT RADIO ECHOES: Around the Arctic Circle, you can't see noctilucent clouds. Glare from the midnight sun overwhelms their blue glow. Even though Rob Stammes can't see the clouds from Lofoton, Norway, he knows they are there. They show themselves as squiggles on a chart recorder, the signature of polar summertime mesospheric echoes (PSMEs):
"I detected strong PMSEs on 02-03 July 2017," reports Stammes. "This is related to widespread noctilucent clouds visible south of us in Europe."
PMSEs are terrestrial radio stations reflected from an altitude of 80 km to 90 km. That part of Earth's upper atmosphere is called the "mesosphere." It is, coincidentally, the same place noctilucent clouds are found. The exact cause of PMSEs is not yet known; theorists have proposed explanations ranging from steep electron density gradients and "dressed aerosols" to gravity waves and turbulence. The echoes are often accompanied by visible NLCs.
Stammes operates a VHF radio observatory in northern Norway. "I use my VHF receiving system generally for signals from auroras and meteors," says Stammes, "but occasionally I pick up PSMEs, which sound quite different from aurora echoes and other reflection mechanisms."
Realtime Space Weather Photo Gallery
Realtime Aurora 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 Jul. 5, 2017, the network reported 19 fireballs.
(19 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]
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 July 5, 2017 there were 1803 potentially hazardous asteroids.
|
Recent & Upcoming Earth-asteroid encounters: Asteroid | Date(UT) | Miss Distance | Velocity (km/s) | Diameter (m) |
2017 MB3 | 2017-Jun-30 | 5 LD | 6.5 | 31 |
2017 MC1 | 2017-Jun-30 | 2.5 LD | 11.6 | 44 |
2017 NB | 2017-Jul-02 | 3.5 LD | 10 | 38 |
2017 MC3 | 2017-Jul-02 | 6.5 LD | 13.2 | 57 |
2017 MO8 | 2017-Jul-03 | 4.1 LD | 10.9 | 22 |
2017 ME4 | 2017-Jul-03 | 5.4 LD | 6.8 | 20 |
2017 MB5 | 2017-Jul-05 | 19 LD | 9.5 | 113 |
2017 MQ7 | 2017-Jul-06 | 17.6 LD | 10.9 | 84 |
2017 MA5 | 2017-Jul-06 | 14.9 LD | 7.9 | 28 |
2017 MP7 | 2017-Jul-08 | 11 LD | 8.2 | 29 |
2017 MC4 | 2017-Jul-11 | 7.6 LD | 20.7 | 150 |
2017 NH | 2017-Jul-12 | 16.6 LD | 7.8 | 158 |
2017 MR8 | 2017-Jul-15 | 3.3 LD | 6.9 | 35 |
2007 MB4 | 2017-Jul-16 | 14.5 LD | 9.6 | 107 |
2017 BS5 | 2017-Jul-23 | 3.1 LD | 5.8 | 54 |
2014 OA339 | 2017-Aug-13 | 12.3 LD | 10 | 47 |
3122 | 2017-Sep-01 | 18.5 LD | 13.5 | 5376 |
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 |
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 13% 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.
| 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 |
| 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 |
| Beautyz for top beauty products reviews and their buying guides |
| Reviews here can help you to pick up best memory foam mattresses. |
| These links help Spaceweather.com stay online. Thank you to our supporters! |
| | | | | |