Its a classic needle-in-a-haystack conundrum. Except the needles are smaller than most bacteria and travelled all the way across the solar system to get to the haystack.
This is the problem that NASA scientists were face with when their Stardust probe returned samples of dust collected from the comet Wild 2 (pronounced Vilt 2) and the Interstellar medium way back in 2006. It was an amazing feat of engineering and orbital mechanics--but after the dust samples safely touched down in Utah--Nasa scientists were face with a simple but HUGELY difficult question:
“How the heck do we even find where all this cosmic dust we caught is?”
The problem was that, even though the collector plate was only the size of your average tennis racket--the particles it caught were probably way-less-than-microscopic in size. Some of these guys would probably get intimidated by how huge bacteria are.
The solution they came up with was elegant and simple. It called on a rag-tag band of 30,000 ordinary folks on the internet to become citizen scientists and take on the hunt for these tiny cosmic snowflakes.
And now, 8 years later--the research team at Berkeley has finally told us that the search ahs paid off.
This was such a difficult problem to solve largely because of the mission parameters Nasa researchers set out for themselves. They not only wanted to catch little bits of dust floating around the solar system, they wanted to keep those dust motes perfectly intact.
Which is hard when you’re trying to catch something going about 6 times faster than a speeding bullet with a tennis racket attached to a robot roaring across the backside of the cosmos.
In the end, scientists settled on the amazing material known as Aerogel. This stuff is basically flash-frozen smoke. Its the same hardness as glass, but its 98% empty space. Aerogel is so incredibly not-dense that the cosmic dust could hit it, slow down, and come to a safe stop without getting damaged in the process. Its an airbag and a holding cell all in one!
So yea, way back in 2003, 200 days before Nasa's Stardust probe was going to intercept comet Wild 2, scientists opened up the probe and stuck out their aerogel tennis racket. One side faced towards Wilt 2, and the other was pointed at the constellation Ophiuchus, which is the direction scientists are pretty sure particles from beyond the solar system would fly from. These particles are part of something called the Interstellar Medium, and if researchers could catch one or two little bits like that, it would unlock all sorts of mysteries about the composition of the universe.
And the collection went well, Stardust captured a whole bunch of material from Wild 2 and dropped it off in Utah.
But that lead to the difficult part. This is where the citizen scientists came in. Researchers at Berkeley took over a million microscope scans from the aerogel plate. It was up to these ordinary folks--who referred to themselves as ‘dusters’--to find the particles. They were looking for signs the dust left behind as they cut through the aerogel before stopping--little carrot shaped streaks they called ‘tracks.’
It was easy enough to find particle tracks--but scientists were only looking for particles that came exactly from the direction of Ophiuchus, which would be the main way they could prove the particles were flying in from beyond the solar system.
But 8 years later scientists have announced that between Berkely and the Dusters, they have found 7 candidates for interstellar dust. This is HUGE. They next step will be cutting those particles out of the aerogel and seeing exactly what they’re made of. Whatever they are, those 7 tracks will become hugely important in future research.
The stardust@home mission is still ongoing and you can still sign up to be a duster and find more of these bits of the cosmos at the link below. In fact, there are TONS of opportunities to join citizen science projects all over the world!
If you’re as obsessed with Martian exploration as much as we are here at Scishow, then you can sign up for Nasa’s ‘Be a Martian’ project, where Citizen Scientists help make better maps of Mars. If you love observing nature, then you should check out the iNaturalist project, which seeks to map biodiversity all over earth. And if you’re not sure what kind of science you’d like to help out with, then Zooniverse.org has HUNDREDS of projects on their website you can look through. Its a great way to start developing your science skills, or just to be a part of the magic that is the scientific process.
Thanks for joining me for SciShow Space. If you want to help us keep exploring the universe, just go to subbable dot com slash sci show. And don’t forget to go to youtube dot com slash sci show space and subscribe!
Description Links:
Stardust@home: http://stardustathome.ssl.berkeley.edu/
Be a Martian: http://beamartian.jpl.nasa.gov/welcome
iNaturalist: http://www.inaturalist.org/
Zooniverse: https://www.zooniverse.org/
Tags:
#scishowSpace #stardust, #comets #NASA #CitizenScience #YouTooCanBeAScientist #CosmicDust #SpaceSnow #InterstellarParticles #SomeOtherMethaphorForTinyBitsOfTheCosmos
Social Media Byline:
Have you ever wanted to be a scientist? FInd out how 30,000 people from the internet found interstellar particles in a NASA space probe and how you can be a Citizen Scientist!
Word Count: 785
Written By: Peter Starr Northrop
Questions? Comments? Just wanna say hi? p.s.northrop@gmail.com
Sources:
http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=1999-003D-01
http://spaceref.com/news/viewpr.html?pid=44370
http://www.sciencemag.org/content/328/5977/483.short
http://www.space.com/26833-nasa-stardust-spacecraft-captured-interstellar-dust.html
