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Today in science: 1st Telstar launch

Telstar was the 1st satellite to relay television signals between Europe and North America. It launched on this date … and helped change the world.  

What’s the July birthstone?

Are you a July baby? Your birthstone, the ruby, is among the most highly prized of gemstones.

Find the Crown of the Scorpion

Here’s another cool asterism, or noticeable pattern of stars. The Scorpion’s Crown consists of just 3 stars.

Tunguska explosion

We celebrate Asteroid Day on June 30 because it’s the anniversary of a 1908 explosion over Siberia that killed reindeer and flattened trees.

NASA’s plans for August 21 eclipse

Not traveling to the centerline of the eclipse? Expect NASA images via 11 spacecraft, at least 3 aircraft, more than 50 high-altitude balloons, and the International Space Station.

How to see a full circle rainbow

It’s possible to see the whole circle of a rainbow – but sky conditions have to be just right. Plus you have to be up high!

Flying with the world’s fastest bird

The peregrine falcon is the fastest bird – and in fact the fastest animal on Earth – when in its hunting dive. Amazing BBC video here.

Top 10 things about brown recluse spiders

It’s their active season. Here are 10 things to know about these venomous spiders that like to live where we do.

Video: Watching solstices and equinoxes from space

See how sunlight falls on Earth’s surface during the solstices and equinoxes, and get a better understanding of why Earth’s tilt causes the seasons.

Does the North Star ever move?

It’s a symbol for constancy, but, if you took its picture, you’d find that the North Star makes its own little circle around the sky’s north pole every day.