Learn to photograph Northern Lights like a pro. Sign up for Peter Rosen's Aurora Photo Courses in Abisko National Park, winner of the TripAdvisor Certificate of Excellence Award 2015. | | |
GEOMAGNETIC STORM: A G1-class geomagnetic storm is in progress on July 4th as Earth enters a high-speed solar wind stream. High-latitude sky watchers should be alert for auroras after nightfall. The hours around local midnight are usually the best times to look. Aurora alerts: text or voice.
SOMETHING NEW: Meteorologist-in-training Matthew Cappucci, a freshman at Harvard, has been reading Spaceweather.com since he was in 8th grade. As part of his career development, he has started making space weather forecast videos in the classic style of an evening weather forecast. Take a look at his 4th of July video and let us know what you think.
ELECTRIC-BLUE RIPPLES IN THE SKY: Summer is the season for noctilucent clouds (NLCs), and July is the month when they are often at their best. Example: These telltale electric-blue ripples appeared over Carnikava, Latvia, on July 3rd:
"The waves were beautiful," says photographer Inta Nuke. "I could see them right through my window." Nuke captured the ripples using a digital camera set at ISO 100. It was a 10 second exposure.
Photographers elsewhere should take note of those settings, because NLCs are spreading, and a photo-op could be coming to a backyard near you.
Noctilucent clouds first appeared in the 19th century after the eruption of super-volcano Krakatoa. At the time, people thought NLCs were caused by the eruption, but long after Krakatoa's ash settled, the clouds remained. In recent years, NLCs have intensified and spread with summer sightings as far south as Utah and Colorado. This could be a sign of increasing greenhouse gases in Earth's atmosphere.
Observing tips: Look west 30 to 60 minutes after sunset when the Sun has dipped 6o to 16o below the horizon. If you see luminous blue-white tendrils spreading across the sky, you may have spotted a noctilucent cloud.
Realtime NLC Photo Gallery
SUMMER SPACE BREW: On June 27th, Spaceweather.com and the students of Earth to Sky Calculus launched a helium balloon to the stratosphere carrying an array of high-energy radiation sensors. The purpose of the flight was to monitor how the upper atmosphere is recovering from the intense geomagnetic storm of June 22-23. (Answer: It has recovered. The radiation environment in the stratosphere is back to normal.) These packets of brewer's yeast went along for the ride:
The yeast packets pictured above traveled 109,904 feet above Earth's surface. En route to the stratosphere, they experienced temperatures as low as -64 C and doses of ionizing radiation more than 50x Earth-normal. Conditions "up there" are akin to the planet Mars.
The test-tube-like object between the two yeast packets is a bubble chamber for measuring neutrons. The dose of neutron radiation measured during the flight was three times higher than the dose of ionizing radiation, amounting to more than 150x Earth-normal.
What kind of beer will these "space yeast" brew? You can find out for yourself. For only $49.95 we will send you a packet of brewer's yeast flown to the edge of space. The following varieties are available: Windsor English-style Ale, BRY-97 American West Coast Ale, Saflager 23, Safale US-05, Safbrew T-58, and Safbrew WB-06. To place your order, contact Dr. Tony Phillips. All proceeds support student research.
Realtime Space Weather Photo Gallery
PING-PONG MOON TRICK: The Moon is nearly full tonight, which means it's the perfect time for a bit of trickery. All you need is a small telescope and a ping-pong ball to create a 3-dimensional Moon small enough to hold between your fingertips. Tom Harradine of Brisbane, Australia, shows how it is done:
"I pointed my telescope at the Moon and held the ping pong ball in front of the eyepiece," explains Harradine. An image of the Moon iluminated the translucent ball. "By adjusting the focus of the telescope and the distance between the ball and the eyepiece, I was able to create a little 3D Moon."
"This works best for the full or nearly-full Moon," he adds.
Good news for tricksters: There are two full Moons this month. The first comes on July 1-2, the second on July 31st. According to modern folklore, the second full Moon is a calendar month is a Blue Moon. So gather your ping pong balls now for a little Blue Moon at the end of July.
Realtime Space Weather Photo Gallery
Realtime Aurora Photo Gallery
Realtime Sprite 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. 4, 2015, the network reported 4 fireballs.
(4 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 4, 2015 there were 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 |
| the underlying science of space weather |
| Web-based high school science course with free enrollment |