The dwarf planet’s famous heart-shaped feature, which NASA’s discovered during its epic July 2015 flyby, drives atmospheric circulation patterns on Pluto, a new study suggests.
Most of the action comes courtesy of the heart’s left lobe, a 600-mile-wide (1,000 kilometers) nitrogen-ice plain called Sputnik Planitia. This exotic ice vaporizes during the day and condenses into ice again at night, causing nitrogen winds to blow, the researchers determined. ( is dominated by nitrogen, like Earth’s, though the dwarf planet’s air is about 100,000 times thinner than the stuff we breathe.)
These winds carry heat, particles of haze and grains of ice westward, staining the ices there with dark streaks.
“This highlights the fact that Pluto’s atmosphere and winds — even if the density of the atmosphere is very low — can impact the surface,” study lead author Tanguy Bertrand, an astrophysicist and planetary scientist at NASA’s Ames Research Center in California, .
And that westward direction is interesting in itself, considering that Pluto spins eastward on its axis. The dwarf planet’s atmosphere therefore exhibits an odd “retrorotation,” study team members said.
Bertrand and his colleagues studied data gathered by New Horizons during the probe’s 2015 close encounter. The researchers also performed computer simulations to model Pluto’s nitrogen cycle and weather, especially the dwarf planet’s winds.
This work revealed the likely presence of westerly winds — a high-altitude variety that races along at least 2.5 miles (4 kilometers) above the surface and a fast-moving type closer to the ground that follows Sputnik Planitia’s western edge.
That edge is bounded by high cliffs, which appear to trap the near-surface winds inside the Sputnik Planitia basin for a spell before they can escape to the west, the new study suggested.
“It’s very much the kind of thing that’s due to the topography or specifics of the setting,” planetary scientist Candice Hansen-Koharcheck, of the Planetary Science Institute in Tucson, Arizona, said in the same statement.
“I’m impressed that Pluto’s models have advanced to the point that you can talk about regional weather,” added Hansen-Koharcheck, who was not involved in the new study.
New Horizons’ Pluto flyby revealed that the dwarf planet is far more complex and diverse than anyone had thought, featuring towering water-ice mountains and weird “bladed” terrain in addition to the photogenic heart (whose official name, Tombaugh Regio, honors the discoverer of Pluto, ).
The , which was published online Tuesday (Feb. 4) in the Journal of Geophysical Research: Planets, reinforces and extends that basic message.
“Sputnik Planitia may be as important for Pluto’s climate as the ocean is for Earth’s climate,” Bertrand said. “If you remove Sputnik Planitia — if you remove the heart of Pluto — you won’t have the same circulation.”
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Christina Koch and Jessica Meir will become the first to partake in history’s only all-women spacewalk aboard the International Space Station (ISS) on October 21.
The originally planned first all-female spacewalk was canceled last March, when NASA announced it only had one suitably fitting spacesuit for the two women aboard the International Space Station. Instead, both women took part in two separate co-ed spacewalks.
The spacesuit that will be worn during the spacewalk is the Extravehicular Mobility Unit (EMU), a specially designed “personal spaceship” of a suit that keeps the astronauts safe in the high-pressure vacuum of space. The spacesuit contains breathing and temperature controls, communication systems, battery power, and offers protection from radiation and space debris. One part of the suit, the hard upper torso (HUT), created the hiccup in the last all-female spacewalk attempt. Both women best fit a medium-sized HUT, but the ISS only had one available.
“Due to a number of factors, ranging from safety to fit and performance, a crewmember may decide in orbit that their size preferences have changed. This is not uncommon, as astronauts’ bodies change on orbit and ground-based training can be different than performing spacewalks in the microgravity environment outside the space station,” wrote NASA in a statement. They added that “when that occurs, the teams on the ground determine what course of action will best accommodate both the astronauts’ preferences and the demands of the space station’s schedule.”
The spacewalk is one of the most dangerous tasks that an astronaut will take part in during their time aboard the ISS. Each typically lasts around 6.5 hours while the astronaut remains tethered to their spacecraft to keep from floating away. Just like in the movies, astronauts wear small backpack-sized units complete with jet thrusters operated by a joystick to help them move around safely.
The October 21 event is one of 10 spacewalks outside of the ISS that are scheduled to occur over the next few weeks, the first five of which are meant to replace outdated nickel-hydrogen batteries on the space station’s truss and the following five to repair the Alpha Magnetic Spectrometer (AMS). The AMS has been attached to the ISS since May 2011 and is used to detect dark matter.
[NASA, Yvette Smith] Take a deep breath. Even if the air looks clear, it is nearly certain that you will inhale millions of solid particles and liquid droplets. These ubiquitous specks of matter are known as aerosols, and they can be found in the air over oceans, deserts, mountains, forests, ice and every ecosystem in between.
If you have ever watched smoke billowing from a wildfire, ash erupting from a volcano or dust blowing in the wind, you have seen aerosols. Satellites like NASA’s Earth-observing satellites, Terra, Aqua, Aura and Suomi NPP, â€œseeâ€ them as well, though they offer a completely different perspective from hundreds of kilometers above Earthâ€™s surface. A version of a NASA model called the Goddard Earth Observing System Forward Processing (GEOS FP) offers a similarly expansive view of the mishmash of particles that dance and swirl through the atmosphere.
The visualization above highlights GEOS FP model output for aerosols on August 23, 2018. On that day, huge plumes of smoke drifted over North America and Africa, three different tropical cyclones churned in the Pacific Ocean, and large clouds of dust blew over deserts in Africa and Asia. The storms are visible within giant swirls of sea salt aerosol (blue), which winds loft into the air as part of sea spray. Black carbon particles (red) are among the particles emitted by fires; vehicle and factory emissions are another common source. Particles the model classified as dust are shown in purple. The visualization includes a layer of night light data collected by the day-night band of the Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP that shows the locations of towns and cities.
The extreme heat is particularly unusual because it is not an El Nio year the phenomenon usually associated with prolonged temperature surges. Instead, scientists say it is driven to a large extent by carbon emissions from car exhausts, power plant chimneys, burning forests and other human sources.
How much these factors loaded the dice in the two- to three-day heatwave during the last week of July was the subject of an attribution study by a consortium of meteorologists and climatologists at the UK Met Office, Oxford University and other prominent European institutions.
It found that the extreme heat in France and the Netherlands, where temperatures peaked above 40C, was made at least 10 times and possibly more than 100 times more likely by climate change. In the UK, which set a record of 38.7C on 25 July, the human impact on the climate made the high temperatures at least two to three times more probable.
There was considerable variation from place to place, but in all the studied locations the scientists said it would have been 1.5C to 3C cooler without climate change.