EXITING THE SOLAR WIND STREAM: After a full week inside, Earth is exiting a stream of solar wind flowing from a large canyon-shaped hole in the sun's atmosphere. NOAA forecasters have lowered the chance of a polar geomagnetic storm on March 7th to 25% as the solar wind speed falls below 600 km/s. Browse: Aurora Photo Gallery.
THE TRANSFORMATION OF VENUS: On March 25th, Venus will pass almost directly between Earth and the sun--an event astronomers call "inferior solar conjunction." As Venus approaches the sun, the planet is turning its night side toward Earth, reducing its luminous glow to a thin sliver. Astrophotographer Raffaello Lena of Rome, Italy, has been monitoring the transformation:
"The progression of the crescent as Venus approaches inferior conjunction is clear," says Lena. "I took these pictures using an 18 cm (7 inch) Mak Cassegrain telescope."
You don't need such a large telescope, however, to see the shape of Venus. Even ordinary binoculars will show the crescent. Amateur astronomers are encouraged to monitor Venus in the lead-up to inferior conjunction. In the nights ahead, the crescent of Venus will become increasingly thin and circular. The horns of the crescent might actually touch when the Venus-sun angle is least on March 25th.
Look for Venus shining brightly in the western sky at sunset--you can't miss it!
ARCTIC SPACE WEATHER BALLOON LAUNCH: Spaceweather.com is going to Sweden--and we're taking a team of student researchers from Earth to Sky Calculus with us. For a week beginning on March 9th we plan to launch a series of space weather balloons equipped with cosmic ray sensors and cameras into the stratosphere above the Arctic Circle. At the same time, Earth to Sky launch teams in Chile and California will be sending up identical payloads, forming an intercontinental balloon network:
We're doing this for three reasons:
1. To understand Earth's changing radiation environment: Regular monitoring of the stratosphere over California shows that cosmic rays have intensified more than 10% since 2015. Because of a recent decline in the solar cycle, more and more cosmic rays are reaching the inner solar system and penetrating the atmosphere of our planet. Earth's magnetic field should protect us against these rays, but geomagnetism is weakening. Globally, Earth's magnetic field has declined in strength by 10% since the 19th century with changes accelerating in recent years, according to measurements by Europe's SWARM satellites. To understand Earth's global response to these changes, we must launch balloons and sample radiation from widely-spaced locations. The upcoming network launch will span three continents, more than 14,000 km of linear distance, and 90+ degrees of latitude.

Above: Satellite data show that Earth's magnetic field is changing: full story.
2. To photograph the Northern Lights: We will be launching balloons from Abisko, Sweden, 250 km inside the Arctic Circle. Abisko is famous for spectacular auroras. One of our payloads will carry a low-light camera capable of photographing these lights from the stratosphere. Even at 120,000 feet, the balloon will be well below the auroras, but we will be a lot closer than any camera on the ground.
3. To sample polar stratospheric clouds: During winter months, the stratosphere above the Arctic Circle sometimes fills with icy clouds so colorful, they are likened to the aurora borealis. Polar stratospheric clouds (PSCs) are a sign of extremely cold temperatures in the stratosphere and some types of PSCs are responsible for ozone destruction. Our space weather balloons can fly right through these clouds, sampling their temperature, pressure, and ambient levels of radiation. We can also photograph them from the inside--a possible first!
Stay tuned for daily updates beginning March 9th.
NORTHERN LIGHTS SPACE PENDANT: To raise money for their trip to the Arctic Circle, on March 2nd the students of Earth to Sky Calculus flew a payload-full of Northern Lights pendants to the edge of space above California. You can have one for $69.95. Each piece of jewelry comes with a greeting card telling the story of the pendant's trip to the stratosphere and certifying its peak altitude: 112,200 feet above Earth's surface.
Bonus: Would you like your pendant to fly above the Arctic Circle as well? Make a note in the COMMENTS box at checkout and we will take your pendant to Sweden for a second trip to the stratosphere.
More far-out gifts may be found in the Earth to Sky Store. All proceeds support STEM education and high-altitude ballooning.
Realtime Space Weather Photo Gallery