How is it that Pluto’s smog looks prettier than our own?
On both planets, smog is caused by a photochemical reaction. Sunlight acts on the chemicals in the atmosphere and creates by-products which we find in smog.
On Earth, the sunlight reacts with nitrogen oxide and creates aldehydes, while on Pluto, sunlight reacts with methane to create acetylene and ethylene. These form hydrocarbon groups and scatter blue light, which is why we see a blue haze!
SELECTS MISSION TO STUDY THE CHURNING CHAOS IN OUR MILKY WAY & BEYOND
NASA has selected a science mission that will measure emissions from the
interstellar medium, which is the cosmic material found between stars. This
data will help scientists determine the life cycle of interstellar gas in our
Milky Way galaxy, witness the formation and destruction of star-forming clouds,
and understand the dynamics and gas flow in the vicinity of the center of our
The Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory (GUSTO)
mission, led by principal investigator of the University of Arizona,
Christopher Walker, will fly an ultralong-duration balloon (ULDB) carrying a
telescope with carbon, oxygen and nitrogen emission line detectors. This unique
combination of data will provide the spectral and spatial resolution
information needed for Walker and his team to untangle the complexities of the
interstellar medium, and map out large sections of the plane of our Milky Way
galaxy and the nearby galaxy known as the Large Magellanic Cloud.
“GUSTO will provide the first complete study of all phases of the stellar life
cycle, from the formation of molecular clouds, through star birth and
evolution, to the formation of gas clouds and the re-initiation of the cycle,”
said Paul Hertz, astrophysics division director in the Science Mission
Directorate in Washington. “NASA has a great history of launching observatories
in the Astrophysics Explorers Program with new and unique observational
capabilities. GUSTO continues that tradition.”
The mission is targeted for launch in 2021 from McMurdo, Antarctica, and is
expected to stay in the air between 100 to 170 days, depending on weather
conditions. It will cost approximately $40 million, including the balloon
launch funding and the cost of post-launch operations and data analysis.
The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, is
providing the mission operations, and the balloon platform where the
instruments are mounted, known as the gondola. The University of Arizona in
Tucson will provide the GUSTO telescope and instrument, which will incorporate
detector technologies from NASA’s Jet Propulsion Laboratory in Pasadena,
California, the Massachusetts Institute of Technology in Cambridge, Arizona
State University in Tempe, and SRON Netherlands Institute for Space Research.
NASA’s Astrophysics Explorers Program requested proposals for mission of
opportunity investigations in September 2014. A panel of NASA and other
scientists and engineers reviewed two mission of opportunity concept studies
selected from the eight proposals submitted at that time, and NASA has
determined that GUSTO has the best potential for excellent science return with
a feasible development plan.
“As you lie on your back, it is natural to assume that you are looking up at the stars, but “up” is just a cultural construct. Neither Earth nor the Milky Way have an up or a down. Indeed, when you stand on Earth’s surface, you are not standing up; rather, you are sticking out into space.
So, as you lie on your back, instead of thinking of yourself as looking up, picture it so that you are on the underside of Earth looking down into the blackness of the night sky. It may take a while, but eventually you will experience all the stars as way down there below you; and you will be surprised that you are not falling down there to join them.
You don’t fall because Earth’s gravitational pull holds you. It is not your weight, but the Earth’s hold that suspends you above the stars. If Earth’s gravitational embrace were to suddenly vanish, you would descend into the dark chasm of stars below.
As you lie there feeling yourself hovering within this gravitational bond while peering down at the billions of stars drifting in the infinite chasm of space, you will have entered an experience of the universe that is not just human and not just biological.
You will have entered a relationship from a galactic perspective, becoming for a moment a part of the Milky Way Galaxy experiencing what it is like to be the Milky Way Galaxy.”
- Excerpt from Developing Ecological Consciousness: The End of Separation by Christopher Uhl
STARS BORN IN WINDS FROM
SUPERMASSIVE BLACK HOLES:
ESO’S VERY LARGE TELESCOPE SPOTS BRAND-NEW TYPE OF STAR FORMATION
Observations using ESO’s Very Large Telescope have revealed stars forming
within powerful outflows of material blasted out from supermassive black holes
at the cores of galaxies. These are the first confirmed observations of stars
forming in this kind of extreme environment. The discovery has many
consequences for understanding galaxy properties and evolution. The results are
published in the journal Nature.
A UK-led group of European astronomers used the MUSE instruments on the Very Large Telescope VLT, at ESO’s Paranal Observatory in Chile to study an ongoing collision between two
galaxies, known collectively as IRAS F23128-5919 ,
that lie around 600 million light-years from Earth. The group observed the
colossal winds of material – or outflows – that originate near the supermassive
black hole at the heart of the pair’s southern galaxy, and have found the first
clear evidence that stars are being born within them .
Such galactic outflows are driven by the huge energy output from the active and
turbulent centres of galaxies.
Supermassive black holes
lurk in the cores of most galaxies, and when they gobble up matter they also
heat the surrounding gas and expel it from the host galaxy in powerful, dense
“Astronomers have thought for a while that conditions within these outflows
could be right for star formation, but no one has seen it actually happening as
it’s a very difficult observation,” comments team leader Roberto Maiolino from
the University of Cambridge. “Our results are exciting because they show
unambiguously that stars are being created inside these outflows.”
The group set out to study stars in the outflow directly, as well as the gas
that surrounds them. By using two of the world-leading VLT spectroscopic
instruments, MUSE and X-shooter, they could carry out a very detailed study of
the properties of the emitted light to determine its source.
Radiation from young stars is known to cause nearby gas clouds to glow in a
particular way. The extreme sensitivity of X-shooter allowed the team to rule
out other possible causes of this illumination, including gas shocks or the
active nucleus of the galaxy.
The group then made an unmistakable direct detection of an infant stellar
population in the outflow . These stars are thought to be less than a few
tens of millions of years old, and preliminary analysis suggests that they are
hotter and brighter than stars formed in less extreme environments such as the
As further evidence, the astronomers also determined the motion and velocity of
these stars. The light from most of the region’s stars indicates that they are
travelling at very large velocities away from the galaxy centre – as would
make sense for objects caught in a stream of fast-moving material.
Co-author Helen Russell (Institute of Astronomy, Cambridge, UK) expands: “The
stars that form in the wind close to the galaxy centre might slow down and even
start heading back inwards, but the stars that form further out in the flow
experience less deceleration and can even fly off out of the galaxy
The discovery provides new and exciting information that could better our
understanding of some astrophysics, including how certain galaxies obtain their
shapes ; how intergalactic space becomes enriched with heavy elements ; and even from where unexplained cosmic infrared background
radiation may arise .
Maiolino is excited for the future: “If star formation is really occurring in
most galactic outflows, as some theories predict, then this would provide a
completely new scenario for our understanding of galaxy evolution.”
 Stars are forming in the outflows at a very rapid rate; the astronomers say that stars totaling
around 30 times the mass of the Sun are being created every year. This accounts
for over a quarter of the total star formation in the entire merging galaxy
 The expulsion of gas through galactic outflows leads to a gas-poor
environment within the galaxy, which could be why some galaxies cease forming
as they age. Although these outflows are most likely to be driven by massive
central black holes, it is also possible that the winds are powered by
supernovae in a starburst nucleus undergoing vigorous star formation.
 This was achieved through the detection of signatures characteristic of
young stellar populations and with a velocity pattern consistent with that
expected from stars formed at high velocity in the outflow.
 Spiral galaxies
have an obvious disc structure, with a distended bulge
of stars in the centre and surrounded by a diffuse cloud of stars called a halo .
Elliptical galaxies are composed mostly of these spheroidal components. Outflow stars that are ejected
from the main disc could give rise to these galactic features.
 How the space between galaxies – the intergalactic medium
– becomes enriched with heavy elements is still an open issue, but outflow
stars could provide an answer. If they are jettisoned out of the galaxy and
then explode as supernovae,
the heavy elements they contain could be released into this medium.
 Cosmic-infrared background radiation, similar to the more famous cosmic
microwave background, is a faint glow in the infrared part
of the spectrum that appears to come from all directions in space. Its origin
in the near-infrared bands, however, has never been satisfactorily ascertained.
A population of outflow stars shot out into intergalactic space may contribute
to this light.
Artist’s impression of a galaxy forming stars within powerful outflows of material blasted out from supermassive black holes at its core. Results from ESO’s Very Large Telescope are the first confirmed observations of stars forming in this kind of extreme environment. The discovery has many consequences for understanding galaxy properties and evolution.Credit:ESO/M. Kornmesser
Dark Spot and Jovian ‘Galaxy’ - This enhanced-color image of a mysterious dark spot on Jupiter seems to reveal a Jovian “galaxy” of swirling storms. Juno acquired this JunoCam image on Feb. 2, 2017, at an altitude of 9,000 miles (14,500 kilometers) above the giant planet’s cloud tops. This publicly selected target was simply titled “Dark Spot.” In ground-based images it was difficult to tell that it is a dark storm. Citizen scientist Roman Tkachenko enhanced the color to bring out the rich detail in the storm and surrounding clouds. Just south of the dark storm is a bright, oval-shaped storm with high, bright, white clouds, reminiscent of a swirling galaxy. As a final touch, he rotated the image 90 degrees, turning the picture into a work of art.