Solar System 10 Things to Know: Planetary Atmospheres

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Every time you take a breath of fresh air, it’s easy to forget you can safely do so because of Earth’s atmosphere. Life on Earth could not exist without that protective cover that keeps us warm, allows us to breathe and protects us from harmful radiation—among other things.

What makes Earth’s atmosphere special, and how do other planets’ atmospheres compare? Here are 10 tidbits:

1. On Earth, we live in the troposphere, the closest atmospheric layer to Earth’s surface. “Tropos” means “change,” and the name reflects our constantly changing weather and mixture of gases.

It’s 5 to 9 miles (8 to 14 kilometers) thick, depending on where you are on Earth, and it’s the densest layer of atmosphere. When we breathe, we’re taking in an air mixture of about 78 percent nitrogen, 21 percent oxygen and 1 percent argon, water vapor and carbon dioxide.

2. Mars has a very thin atmosphere, nearly all carbon dioxide. Because of the Red Planet’s low atmospheric pressure, and with little methane or water vapor to reinforce the weak greenhouse effect (warming that results when the atmosphere traps heat radiating from the planet toward space), Mars’ surface remains quite cold, the average surface temperature being about -82 degrees Fahrenheit (minus 63 degrees Celsius).

3. Venus’ atmosphere, like Mars’, is nearly all carbon dioxide. However, Venus has about 154,000 times more carbon dioxide in its atmosphere than Earth (and about 19,000 times more than Mars does), producing a runaway greenhouse effect and a surface temperature hot enough to melt lead. A runaway greenhouse effect is when a planet’s atmosphere and surface temperature keep increasing until the surface gets so hot that its oceans boil away.

4. Jupiter likely has three distinct cloud layers (composed of ammonia, ammonium hydrosulfide and water) in its “skies” that, taken together, span an altitude range of about 44 miles (71 kilometers). The planet’s fast rotation—spinning once every 10 hours—creates strong jet streams, separating its clouds into dark belts and bright zones wrapping around the circumference of the planet.

5. Saturn’s atmosphere—where our Cassini spacecraft ended its 13 extraordinary years of exploration of the planet—has a few unusual features. Its winds are among the fastest in the solar system, reaching speeds of 1,118 miles (1,800 kilometers) per hour. Saturn may be the only planet in our solar system with a warm polar vortex (a mass of swirling atmospheric gas around the pole) at both the North and South poles. Also, the vortices have “eye-wall clouds,” making them hurricane-like systems like those on Earth.

Another uniquely striking feature is a hexagon-shaped jet streamencircling the North Pole. In addition, about every 20 to 30 Earth years, Saturn hosts a megastorm (a great storm that can last many months).

6. Uranus gets its signature blue-green color from the cold methane gas in its atmosphere and a lack of high clouds. The planet’s minimum troposphere temperature is 49 Kelvin (minus 224.2 degrees Celsius), making it even colder than Neptune in some places. Its winds move backward at the equator, blowing against the planet’s rotation. Closer to the poles, winds shift forward and flow with the planet’s rotation.

7. Neptune is the windiest planet in our solar system. Despite its great distance and low energy input from the Sun, wind speeds at Neptune surpass 1,200 miles per hour (2,000 kilometers per hour), making them three times stronger than Jupiter’s and nine times stronger than Earth’s. Even Earth’s most powerful winds hit only about 250 miles per hour (400 kilometers per hour). Also, Neptune’s atmosphere is blue for the very same reasons as Uranus’ atmosphere.

8. WASP-39b, a hot, bloated, Saturn-like exoplanet (planet outside of our solar system) some 700 light-years away, apparently has a lot of water in its atmosphere. In fact, scientists estimate that it has about three times as much water as Saturn does.

9. A weather forecast on “hot Jupiters”—blistering, Jupiter-like exoplanets that orbit very close to their stars—might mention cloudy nights and sunny days, with highs of 2,400 degrees Fahrenheit (about 1,300 degrees Celsius, or 1,600 Kelvin). Their cloud composition depends on their temperature, and studies suggest that the clouds are unevenly distributed.

10. 55 Cancri e, a “super Earth” exoplanet (a planet outside of our solar system with a diameter between Earth’s and Neptune’s) that may be covered in lava, likely has an atmosphere containing nitrogen, water and even oxygen–molecules found in our atmosphere–but with much higher temperatures throughout. Orbiting so close to its host star, the planet could not maintain liquid water and likely would not be able to support life.

 

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New Magnetic Process in Space

Just as gravity is one key to how things move on Earth, a process called magnetic reconnection is key to how electrically-charged particles speed through space. Now, our Magnetospheric Multiscale mission, or MMS, has discovered magnetic reconnection – a process by which magnetic field lines explosively reconfigure – occurring in a new and surprising way near Earth.
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Invisible to the eye, a vast network of magnetic energy and particles surround our planet — a dynamic system that influences our satellites and technology. The more we understand the way those particles move, the more we can protect our spacecraft and astronauts both near Earth and as we explore deeper into the solar system.

Earth’s magnetic field creates a protective bubble that shields us from highly energetic particles that stream in both from the Sun and interstellar space. As this solar wind bathes our planet, Earth’s magnetic field lines get stretched. Like elastic bands, they eventually release energy by snapping and flinging particles in their path to supersonic speeds.

That burst of energy is generated by magnetic reconnection. It’s pervasive throughout the universe — it happens on the Sun, in the space near Earth and even near black holes.

Scientists have observed this phenomenon many times in Earth’s vast magnetic environment, the magnetosphere. Now, a new study of data from our MMS mission caught the process occurring in a new and unexpected region of near-Earth space. For the first time, magnetic reconnection was seen in the magnetosheath — the boundary between our magnetosphere and the solar wind that flows throughout the solar system and one of the most turbulent regions in near-Earth space.

The four identical MMS spacecraft — flying through this region in a tight pyramid formation — saw the event in 3D. The arrows in the data visualization below show the hundreds of observations MMS took to measure the changes in particle motion and the magnetic field.

The data show that this event is unlike the magnetic reconnection we’ve observed before. If we think of these magnetic field lines as elastic bands, the ones in this region are much smaller and stretchier than elsewhere in near-Earth space — meaning that this process accelerates particles 40 times faster than typical magnetic reconnection near Earth. In short, MMS spotted a completely new magnetic process that is much faster than what we’ve seen before.

What’s more, this observation holds clues to what’s happening at smaller spatial scales, where turbulence takes over the process of mixing and accelerating particles. Turbulence in space moves in random ways and creates vortices, much like when you mix milk into coffee. The process by which turbulence energizes particles in space is still a big area of research, and linking this new discovery to turbulence research may give insights into how magnetic energy powers particle jets in space.

Keep up with the latest discoveries from the MMS mission: @NASASun on Twitter and Facebook.com/NASASunScience.

 

 

Cráteres de la Luna

 

1° From crater Theophilus (100km diameter) below to crater Langrenus above.

2° From bottom to top, dark titanium rich lava in the Sea of Fertility then the diamond shaped patch is the Marsh of Sleep. Small bright crater Proclus is thought to be a recent impact crater and has thrown out bright ejecta that is much lighter than the surrounding ancient weathered rock. Above is the rather hexagonal Mare Crisium.

3° From the Sinus Iridium top left through the Mare Imbrium with the Alpine Valley in the centre. (This original image is horizontal)

4° At the middle and bottom of this image, sunlight is shining on a mountain peak in the Alexander crater which lies beyond the day/night terminator.

Image credit: John Purvis

 

All About That (Nucleic) Base

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Studying DNA Aboard the International Space Station

What do astronauts, microbes and plants all have in common? Each relies on DNA – essentially a computer code for living things – to grow and thrive. The microscopic size of DNA, however, can create some big challenges for studying it aboard the International Space Station.

The real question about DNA in space: but why, tho?

Studying DNA in space could lead to a better understanding of microgravity’s impact on living organisms and could also offer ways to identify unknown microbes in spacecraft, humans and the deep space locations we hope to visit one day.

Most Earth-based molecular research equipment is large and requires significant amounts of power to run. Those are two characteristics that can be difficult to support aboard the station, so previous research samples requiring DNA amplification and sequencing had to be stored in space until they could be sent back to Earth aboard a cargo spacecraft, adding to the time required to get results.

Fun science pro tip: amplification means to make lots and lots of copies of a specific section of DNA.

However, all of that has changed in a few short years as we’ve worked to find new solutions for rapid in-flight molecular testing aboard the space station.

“We need[ed] to get machines to be compact, portable, robust, and independent of much power generation to allow for more agile testing in space,” NASA astronaut and molecular biologist Kate Rubins said in a 2016 downlink with the National Institutes of Health.

The result? An advanced suite of tabletop and palm-sized tools including MinION, miniPCR, and Wet-Lab-2, and more tools and processes on the horizon.

The timeline:

Space-based DNA testing took off in 2016 with the Biomolecule Sequencer.

Comprised of the MinION sequencer and a Surface Pro 3 tablet for analysis, the tool was used to sequence DNA in space for the first time with Rubins at the helm.

In 2017, that tool was used again for Genes in Space-3, as NASA astronaut Peggy Whitson collected and tested samples of microbial growth from around the station.

Alongside MinION, astronauts also tested miniPCR, a thermal cycler used to perform the polymerase chain reaction. Together these platforms provided the identification of unknown station microbes for the first time EVER from space.

This year, those testing capabilities translated into an even stronger portfolio of DNA-focused research for the orbiting laboratory’s fast-paced science schedule. For example, miniPCR is being used to test weakened immune systems and DNA alterations as part of a student-designed investigation known as Genes in Space-5.

The study hopes to reveal more about astronaut health and potential stress-related changes to DNA created by spaceflight. Additionally, WetLab-2 facility is a suite of tools aboard the station designed to process biological samples for real-time gene expression analysis.

More tools for filling out the complete molecular studies opportunities on the orbiting laboratory are heading to space soon.

“The mini revolution has begun,” said Sarah Wallace, our principal investigator for the upcoming Biomolecule Extraction and Sequencing Technology (BEST) investigation. “These are very small, efficient tools. We have a nicely equipped molecular lab on station and devices ideally sized for spaceflight.”

BEST is scheduled to launch to the station later this spring and will compare swab-to-sequencer testing of unknown microbes aboard the space station against current culture-based methods.

Fast, reliable sequencing and identification processes could keep explorers safer on missions into deep space. On Earth, these technologies may make genetic research more accessible, affordable and mobile.

To learn more about the science happening aboard the space station, follow @ISS_Research for daily updates. For opportunities to see the space station pass over your town, check out Spot the Station.

 

 

Explain why earth can’t be flat Thx

The_Earth_seen_from_Apollo_17

This is a simple and solved case. The problem is that there are people who want to draw attention to themselves, and end up inventing these things.

There are several earth images taken from space to prove this.

Sunspots

Sunspots are temporary phenomena on the Sun’s photosphere that appear as spots darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic field flux that inhibit convection. Sunspots usually appear in pairs of opposite magnetic polarity. Their number varies according to the approximately 11-year solar cycle.

Individual sunspots or groups of sunspots may last anywhere from a few days to a few months, but eventually decay. Sunspots expand and contract as they move across the surface of the Sun, with diameters ranging from 16 km (10 mi) to 160,000 km (100,000 mi). The larger variety are visible from Earth without the aid of a telescope. They may travel at relative speeds, or proper motions, of a few hundred meters per second when they first emerge.

Indicating intense magnetic activity, sunspots accompany secondary phenomena such as coronal loops, prominences, and reconnection events. Most solar flares and coronal mass ejections originate in magnetically active regions around visible sunspot groupings