[slate]
Right so we live in a
galaxy. It's called the Milky Way. It contains billions of stars including our
own sun. And it looks a lot like these two galaxies here in this Hubble
27th anniversary image that we just released a few weeks ago.
And today we have a brand new image to show you. This is from the Frontier Fields programs.
It's a galaxy cluster. You see thousands of galaxies in this
image. Most of them look more like fuzzy footballs rather than spiral disks.
And these footballs are all held together by gravity and they make up
this massive cluster that's one of the most massive structures in the universe.
[slate]
Right so Hubble has it's own super vision
and in this image it's using one of nature's superpowers called gravitational lensing
to boost it's vision. And so every galaxy bends space
according to Einstein's relativity and you can see light travel
around, it follows that curvature. And when you have a massive cluster
of galaxies, light can take multiple paths around that galaxy cluster
You see multiple images of distant galaxies. You also see them magnified by
gravitational lens. And as you see in this one image of
a spiral galaxy, you see five images of that galaxy
thanks to this gravitational lensing effect. And if you look off to the side
you see an even more distant galaxy. This is a galaxy that's over
13 billion light years away. So we're seeing it as it was almost at
the beginning of time. Soon after the big bang, a few hundred million years
after. And if you zoom out a bit you two other images
of this same galaxy. So we see three images of this distant galaxy
magnified thanks to gravitational lensing and a little something called dark matter.
[slate]
Right so dark matter is this mysterious
stuff that's all around us. We don't know what it is. It makes up most of the stuff
in the universe. But we can't feel it and we can't see it. But we know that it's
there in part because of this lensing effect. The lensing effect is much stronger than it would be
without this extra mass. We also know that every galaxy
has dark matter because when we look at these spiral galaxies we can
measure how fast they spin and we realize that if it weren't for this
dark matter holding them together that all the stars would fly apart. So
dark matter is really a good thing. And you could call dark matter the guardian of the galaxy.
[slate]
Right so Hubble is
27 years old and still but is still in great shape. The astronauts have gone
to service it multiple times and repair things as needed and add new instruments
And we expect Hubble to keep obtaining great images
like these that we can show you sometime and we expect
Hubble to overlap with the next great space telescope
Hubble's successor the James Webb Space Telescope. And that telescope will
be even larger. It has a bigger mirror so it can see even more distant galaxies.
Fainter things. And it also does that in part by
looking in the infrared which will enable us to see the universe in a whole new
light and we'll be able to see the first galaxies that formed in the universe.
[slate]
Right so these galaxy clusters
the Frontier Fields program imaged six of them. The program's now complete
and it's, there are amazing because they are the most massive structure ever to
form in the history of the universe. And this lensing effect is great, it helps us
map out the dark matter. We've learned a little bit about dark matter
but we don't know too much about it. Also acting as these lenses we're able to
see the more distant universe more efficiently than if we didn't have this lens.
We've now seen 97 percent of the way back to to the Big Bang.
And we're still missing that last 3 percent that with the James Webb Space
Telescope and also boosted by lensing we should be able to see
the first missing three percent of our cosmic history to see the first galaxies form.
[slate]
So to see these beautiful images and many more
of Hubble you can go to nasa.gov/hubble and you can also follow Hubble on
Twitter @NASAHubble.