A MINOR STREAM OF SOLAR WIND: Earth is entering a stream of solar wind flowing from a small hole in the sun's atmosphere. So far the wind speed is relatively low (< 400 km/s) and geomagnetic storms are not expected. Aurora alerts: SMS Text.
INFERIOR CONJUNCTION OF VENUS: On June 3rd, Venus will pass almost directly between Earth and the sun--an event astronomers call "inferior conjunction." This is changing the face of Venus in an extraordinary way. The planet has become an slender crescent, growing thinner every night. Radu Anghel sends these pictures from Bacau, Romania:
"Even 7 days has made a huge difference," says Anghel. "Venus's changing shape is easy to spot even with a pair of binoculars."
Venus is "slenderizing" because it is turning its night side toward Earth. As Venus approaches the sun, only an increasingly narrow sliver of Venus's dayside is visible from here. It's like a miniature version of the crescent Moon.
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 June 3rd.
Bonus: Look for Venus in the western sunset sky this week, and you'll see something extra. Mercury is approaching Venus for a conjunction on May 21st and 22nd. Then, the crescent Moon joins the show on May 23rd and 24th. It's a great way to end the day. Sky maps: May 19, 20, 21, 22, 23, 24.
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WHEN LIGHTNING STRIKES A RAINBOW: Raindrops are marvelous things. And if you think all they do is make you wet, think again. Yesterday in Atwater, California, Richard Sears captured two beautiful manifestations of rain in a single shot--a rainbow and lightning:
"A rapidly developing thundercell announced itself with a wild thunderstorm," says Sears. "Just as the setting sun broke through the clouds in the west, a rainbow appeared and a lightning bolt passed through it."
Peaceful rainbows and violent lightning may seem like unlikely relatives, but they do have a common origin. Raindrops make rainbows by reflecting sunlight, breaking the beams of light into their constituent RGB colors. Raindrops also make lightning. Frozen droplets in convective thunderclouds bump and rub together, creating electric charges akin to woolen socks rubbing against carpet. When the charge builds up enough--crack! A white-hot bolt lances across the sky.
"I was lucky to catch them both," says Sears. "What a spectacular show!"
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THE SPACE HAMMER: Are you looking for a far-out Father's Day gift? Consider the Space Hammer. On May 2nd, the students of Earth to Sky Calculus flew a payload of hammers to the edge of space, 35.0 km (115,000 feet) above Earth's surface onboard a high altitude helium balloon. You can have one for $97.95:
These compact 8 oz. hammers are light enough to fly on a balloon yet dense enough to deliver a powerful blow. The magnetic head holds a nail for one-handed starting, and the stubby 6 in. length is perfect for tight work areas.
Each space hammer comes with a unique gift card showing the tool floating at the top of Earth's atmosphere. The interior of the card tells the story of the flight and confirms that this gift has been to the edge of space and back again.
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
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