(Intro)

You know what's incredibly exciting? Dust! Because I'm talking about dust from deep space, and we have it in our possession! Well, a little of it anyway.

Last week, NASA announced that it had identified particles of interstellar dust that was collected by the Stardust Spacecraft. This is the first time we've ever had any material from outside the solar system in a lab here on earth.

NASA launched the Stardust craft in 1999 to buzz around our solar system just to collect dust. In 2006, Stardust, dutifully sent its samples back to earth, becoming the first mission to return samples not only from the moon, but from beyond the edges of the solar system.

Interstellar dust fills the spaces between star systems and it plays a major role in our universe as the medium where many cosmic events happen. It absorbs radiation from stars, which makes it a low level energy source that helps catalyze the formation of new stars, and its surface area also provides space for the formation of some of the universe's most abundant chemicals, like molecular hydrogen.

You know how we always talk about celestial objects forming from clouds of gas and dust? Well this is the dust! But as important as we think this dust is, we have never observed it directly before. That's why Stardust was sent to a particular patch of the solar system where computer models predicted the craft would have the best chance of capturing some of it, based on factors like solar radiation and gravitation.

So Stardust passed through this area twice, holding out an apparatus the size of tennis racket that was filled with gel to collect the passing particles. Ever since Stardust sent that payload home in 2006, NASA, with the help of hundreds of citizen scientists, has been pouring over thousands of intact particles, and melted remnants of particles, using x-ray microscopes to study there chemical composition.

But, unfortunately, all but seven of these particles contained compounds that appeared to come from the Stardust craft itself, like Aluminum, but the remaining seven were surprisingly diverse in composition, structure and size. Some had a snow-flake-like crystalline structure, for instance, and some contained surprising compounds, like a magnesium-iron silicate mineral called Olivine. It's surprising because compounds like Olivine, while not organic, are pretty complex and, as we've talked about before, the heavier elements that go into them can only be forged inside older stars, like Red Giants and, in some cases, Supernovae.

NASA says it plans to study these tiny grains for another two or three years, but for now, we can say we've gotten our first glimpse of what stuff out there is really like. 

And here's something spectacular you can look at right now - the closest planetary conjunction of the year.

A conjunction is where two or more celestial bodies appear to meet when viewed from Earth, and this conjunction is a special treat because it involves the two brightest planets in the sky - Jupiter and Venus.

On August 18th, Jupiter and Venus were only two-tenths of a degree apart as seen from Earth, less than half the apparent diameter of the moon. But that's just from our perspective, Venus was actually 250 million kilometers away, and Jupiter four times farther. Thanks to the illusion of perspective, we can see several planetary conjunctions like this in a month.

Even more frequent is the conjunction of bodies in the night sky involving the moon. On August 22nd and 23rd the Crescent moon will appear in the sky next to both Venus and and Jupiter, forming a triple conjunction. This rendezvous between Jupiter and Venus only happens once every thirteen months, but it doesn't always happen far enough away from the sun that we can see it at night. So have a look if you happen to be up early because the best viewing will be just before dawn, and, if you sleep through it, on August 27th Mars and Saturn will form another conjunction, appearing about three and half degrees apart. It'll be cool, even if it's only an illusion.

Thanks as always for watching SciShow Space News and, if you want to keep exploring the universe with us, check out subbable.com/scishow to learn how you can help support us, and don't forget to go to youtube.com/scishowspace and subscribe.