Hello Space Fans and welcome to another edition of Space Fan News.
This week, astronomers using data from NASA's Spitzer and Kepler space telescopes have created
the first ever cloud map of an exoplanet.
Kepler-7b, one of the first exoplanets discovered by the Kepler Space Telescope is gas giant
planet one and a half times the radius of Jupiter.
Astronomers observed this planet with Spitzer and Kepler for more than three year and were
able to produce a very low-resolution map of this giant planet.
Using Kepler's visible-light observations of Kepler-7b's moon-like phases they were
able to build a rough map of the planet that showed a bright spot on its western hemisphere.
But these data were not enough on their own to decipher whether the bright spot was coming
from clouds or heat.
For that, they used the Spitzer Space Telescope, an awesome infrared telescope.
Like Kepler, Spitzer can look at a star system as a planet orbits around the star.
Spitzer's ability to detect infrared light means it was able to measure Kepler-7b's temperature,
estimating it to be between 1,500 and 1,800 degrees Fahrenheit (1,100 and 1,300 Kelvin).
It turns out this is relatively cool for a planet that orbits so close to its star -- it's
only 0.06 astronomical units away from the star around 9 million kilometers -- and, according
to astronomers, it is too cool to be the source of light Kepler observed.
Instead, they determined, light from the planet's star is bouncing off cloud tops located on
the west side of the planet.
According to the map, the planet is marked by high clouds in the west and clear skies
in the east and Kepler-7b reflects much more light than most gas giants found so far and
unlike clouds on Earth, the cloud patterns here do not seem to change very much over
time, which indicates a remarkably stable climate.
So there you have it folks, this is the first time we have measured and identified cloud
structures on a distant world outside of our solar system.
What's also very cool here is these observations are an early step towards using similar techniques
to study the atmospheres of planets more like the Earth.
Just like downtown.
Next, astronomers using the 10 meter HIRES Spectrograph at the Keck Observatory in Hawaii
and the Large Binocular Telescope in Arizona have made direct observations of primordial
hydrogen, the stuff created straight from the Big Bang.
How did they see it?
They took spectra o the light that was shining through a distant galaxy that came from a
very distant quasar oriented directly behind it from Earth's point of view.
This really cool cosmic coincidence allowed us to look at light that had passed through
one of the earliest star forming galaxies in the universe, some 10 billion light years
away.
This makes it one of the earliest galaxies we've ever seen.
Looking at the light from this galaxy is tough enough but with the additional light coming
from the quasar, that light allowed astronomers to see gas flowing into the galaxy.
They would never have seen this gas without that distant light.
The reason this is important is that we are still trying to build a picture of how galaxies
first came into existence and current theories tell us that they were once fed from a vast
reservoir of pristine hydrogen floating throughout intergalactic space.
Put there by the Big Bang.
About 10 billion years ago, these early galaxies were forming stars at a furious pace, nearly
one hundred times their current rate.
Now to get so many stars so quickly means you need a steady flow of cosmic fuel, fed
into galaxies in long thin, cold streams.
Now testing these ideas has proven problematic because these gas streams at the edges of
galaxies are very thin and so rarified that they emit very little light on their own.
So as you can imagine, this extra light from the quasar is what made it possible to see
this gas at all.
But you may be asking, how do they know it's from the Big Bang and not just some regular
gas from stars long since dead?
Good question.
The crucial element here was the detection of deuterium in the spectrum.
Deuterium is a stable isotope of hydrogen (it has an extra neutron in the nucleus) and
cosmologists have demonstrated that hydrogen and helium and their stable isotopes like
deuterium were all synthesized just minutes after the Big Bang, when the Universe was
hot enough to power nuclear reactions.
All the heavier elements like carbon, nitrogen, etc were created much later in the hot nuclear
furnaces of stars.
Because deuterium is fragile, it could not survive the hostile physical conditions in
the centers of stars
So the discovery of deuterium in the gas confirms that the gas falling onto the galaxy must
be the pristine material left over from the Big Bang.
Finally, some commentary.
Many of you have been asking me if I've been affected by the government shutdown.
I'm not directly affected, I still go to work everyday and I'm still getting a paycheck
because the Space Telescope Science Institute is a NASA contractor, operated by an organization
called AURA which runs observatories all over the world.
Also, NASA has deemed the Hubble Space Telescope necessary so it is till allowed to continue
on its observing program and we continue to process the data and science is still coming
out of Hubble.
But, I found out earlier this week, as did all of you, that 97% of NASA is shutdown.
By comparison, only 14% of the NSA is.
Oh what a difference an A makes.
And the S doesn't mean the same.
And the last A doesn't match.
But my point is: PRIORITIES!
Look at what we find important.
Reading my email is more vital to our national interests than exploring space and discovering
new things about the universe.
GAAA!
So yes, until all my friends and colleagues at NASA are allowed to come to work and do
their very important jobs, yes this shutdown affects me.
It affects all of us.
That's it for this week Space Fans, thank you for watching and as always, Keep Looking
Up!