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FAQs

What makes Venus the brightest planet?

Venus and Jupiter in conjunction on June 30, 2015, as captured by Mohamad Fadzli in Melaka, Malaysia.

Venus and Jupiter in conjunction on June 30, 2015, as captured by Mohamad Fadzli in Melaka, Malaysia.

Venus is much brighter than any other planet viewed in Earth’s sky. It’s the third-brightest object in the sky, after the sun and moon, and right now it’s heading for another time of greatest brilliancy around July 10, 2015. Click the links inside to learn why Venus is so bright, and when to see it as its brightest in 2015.

How do fireworks get their colors?

Photo credit: Jeff Golden

Photo credit: Jeff Golden

If you’re celebrating the 4th of July by attending a fireworks display, maybe you’ll look up and wonder: What creates those red, orange, yellow, green, blue and purple colors exploding in the night sky?

What’s the birthstone for July?

Photo credit:  Shutterstock

Photo credit: Shutterstock

Happy birthday to all you July babies! Your birthstone, the ruby, is among the most highly prized of gemstones. Large rubies are harder to find than large diamonds, emeralds and sapphires.

When will all five visible planets appear simultaneously?

planets

All five visible planets will appear together in the morning sky early next year – from about January 20 to February 20, 2016. That hasn’t happened since 2005. Details inside.

Can a human singing voice shatter glass?

If you run a damp finger along the rim of a glass, you might hear a faint, ghostly hum – the resonant frequency of the glass. To shatter the glass, a singer’s voice has to match that frequency, or pitch, at an extremely loud level, and the glass must have microscopic defects.

Why isn’t hottest weather at year’s longest day?

You know it's not when ... (Image by Flickr user Katerha

You know it’s not when … Image by Flickr user Katerha

Solstice – year’s longest day for northern part of Earth – was Sunday. But our hottest weather is still to come. Likewise, the coldest weather is ahead for S. Hemisphere.

Can you see a whole circle rainbow?

View larger. | Full circle rainbow was captured over Cottesloe Beach near Perth, Australia in 2013 by Colin Leonhardt of Birdseye View Photography.  He was in a helicopter flying between a setting sun and a downpour.   Used with permission.  Order prints of this photo.

View larger. | Full circle rainbow was captured over Cottesloe Beach near Perth, Australia in 2013 by Colin Leonhardt of Birdseye View Photography. He was in a helicopter flying between a setting sun and a downpour. Used with permission. Order prints of this photo.

It is indeed possible to see the whole circle of a rainbow – but conditions have to be just right.

Why do fireflies light up?

“Fireflies on top of the wave of grass and overflowing. Biggest firefly show in years.” by Eileen Claffey, June, 2015.

Fireflies are sometimes called lightning bugs. Many a child has spent a summer evening chasing them. And maybe you’ve wondered – how and why are these insects able to light up?

Measuring sea level on a dynamic Earth

Image credit: Wally Gobetz

Image credit: Wally Gobetz

Warming temps, and the rise and fall of coasts, complicate measurements of sea level. How do scientists establish sea level on a constantly changing Earth?

How much do oceans add to world’s oxygen?

Phytoplankton - the foundation of the oceanic food chain. image via NOAA

Phytoplankton – the foundation of the oceanic food chain. Scientists estimate that phytoplankton contribute between 50 to 85 percent of the oxygen in Earth’s atmosphere. Image via NOAA

Scientists agree that there’s oxygen from ocean plants in every breath we take.