Merging Galaxies And Droplets Of Starbirth

We’re Way Below Average! Astronomers Say Milky Way Resides In A Great Cosmic Void

“If there weren’t a large cosmic void that our Milky Way resided in, this tension between different ways of measuring the Hubble expansion rate would pose a big problem. Either there would be a systematic error affecting one of the methods of measuring it, or the Universe’s dark energy properties could be changing with time. But right now, all signs are pointing to a simple cosmic explanation that would resolve it all: we’re simply a bit below average when it comes to density.”

When you think of the Universe on the largest scales, you likely think of galaxies grouped and clustered together in huge, massive collections, separated by enormous cosmic voids. But there’s another kind of cluster-and-void out there: a very large volume of space that has its own galaxies, clusters and voids, but is simply higher or lower in density than average. If our galaxy resided near the center of one such region, we’d measure the expansion rate of the Universe to be higher-or-lower than average when we used nearby techniques. But if we measured the global expansion rate, such as via baryon acoustic oscillations or the fluctuations in the cosmic microwave background, we’d actually arrive at the true, average rate.

We’ve been seeing an important discrepancy for years, and yet the cause might simply be that the Milky Way lives in a large cosmic void. The data supports it, too! Get the story today.

New Discoveries about Star Formation in the Flame Nebula

Stars are often born in clusters, in giant clouds of gas and dust. Astronomers have studied two star clusters using NASA’s Chandra X-ray Observatory and infrared telescopes and the results show that the simplest ideas for the birth of these clusters cannot work.

This composite image shows one of the clusters, NGC 2024, which is found in the center of the so-called Flame Nebula about 1,400 light years from Earth. In this image, X-rays from Chandra are seen as purple, while infrared data from NASA’s Spitzer Space Telescope are colored red, green, and blue.

A study of NGC 2024 and the Orion Nebula Cluster, another region where many stars are forming, suggest that the stars on the outskirts of these clusters are older than those in the central regions. This is different from what the simplest idea of star formation predicts, where stars are born first in the center of a collapsing cloud of gas and dust when the density is large enough.

Credit: NASA/Spitzer/Chandra

A little more help for focusing-on beginers: In terms of cognitive demand, it is more difficult to focusing on your ongoing task when you have a long to-do list than when only a few more tasks left. So I recommend you to try making schedule with less than 5 tasks a day. It will be much easier to organize work of different fields or of different shades of cognitive demand.

How focusing (aka. not multi-tasking) changed my study life

I had heard it occasionally - that multi-tasking was actually not good for the quality of whatever task I was doing. It made sense, but I loved mult-tasking so much. It gave me the illusion of productivity. 

Until I actually tried focusing for a while, did I realise how much I was actually losing by multi-tasking -  educationally and emotionally. Scrolling through tumblr during boring parts of a lecture seemed fine, since there were notes and it probably wouldn’t be tested in such depth anyway. Eating, while scrolling through social media, while watching a tv show, while messaging someone on facebook seemed ‘productive’. 

It turns out it was the opposite. It may seem fine, and at times it may actually be okay, but what matters is the principle. Dedicating your whole being to one task, focusing on it, produces much better results. It’s a quality over quantity thing. It also helped to calm me down emotionally - I used to always feel rushed, like there was so many things to do but not enough time to do them. Focusing on one task at a time - though it was hard at first - helped slow me down because I did everything properly, and didn’t have the feeling like I needed to go back and do things over again. 

Focusing on one thing wholly is also a form of practising mindfulness. Mindfulness ‘meditation’ isn’t something that requires you to sit down and meditate - it can be applied to our daily life. 

Since I started practising this mindful skill of focus, I’ve become much calmer, it’s been so much easier to stay on top of my work load and meet deadlines, I don’t feel rushed, I don’t feel unprepared or unorganised, and I do more quality work than when I used to multi-task.

There are times for multi-tasking and times for focus. Find the right balance and enjoy the task in front of you.

Drops of a liquid can often join a pool gradually through a process known as the coalescence cascade (top left). In this process, a drop sits atop a pool, separated by a thin air layer. Once that air drains out, contact is made and part of the drop coalesces. Then a smaller daughter droplet rebounds and the process repeats.

A recent study describes a related phenomenon (top right) in which the coalescence cascade is drastically sped up through the use of surfactants. The normal cascade depends strongly on the amount of time it takes for the air layer between the drop and pool to drain. By making the pool a liquid with a much greater surface tension value than the drop, the researchers sped up the air layer’s drainage. The mismatch in surface tension between the drop and pool creates an outward flow on the surface (below) due to the Marangoni effect. As the pool’s liquid moves outward, it drags air with it, thereby draining the separating layer more quickly. The result is still a coalescence cascade but one in which the later stages have no rebound and coalesce quickly. (Image and research credit: S. Shim and H. Stone, source)

How Do Volcanoes Make Lightning?

“Volcanic lightning appears to occur most frequently around volcanoes with large ash plumes, particularly during active stages of the eruption, where flowing, molten lava creates the largest temperature gradients. The phenomena of lightning has been exquisitely recorded around a number of recent volcanic eruptions, including Iceland’s Eyjafjallajökull, Japan’s Sakurajima, Italy’s Mt. Etna, and Chile’s Puyehue, Calbuco and Chaiten volcanoes. But what you may not know is this phenomenon was not only captured during Mt. Vesuvius’ last eruption in 1944, but was accurately described nearly 2,000 years ago when it erupted all the way back in the year 79!”

Volcanoes are some of the most potentially destructive natural phenomena known to occur on our world. The most violent eruptions feature not only lava, but soot, ash, volatile gases, and even enormous chunks of rock hurled great distances. What you might not realize, however, is just how frequently these eruptions are accompanied by another spectacular show: volcanic lightning. Lightning isn’t only found in thunderstorms or other great electrical discharges between the clouds and the ground, but is produced in volcanic eruptions all throughout the world, and throughout history as well. After countless generations, where we wondered what could produce such an unusual but spectacular show, we’ve finally figured it out.

Come get the science behind how volcanoes make lightning, and enjoy some of the greatest photographs of this phenomena humanity’s ever taken!

Solar System: Things to Know This Week

There’s even more to Mars.

1. Batten Down the Hatches

Good news for future astronauts: scientists are closer to being able to predict when global dust storms will strike the Red Planet. The winds there don’t carry nearly the same force that was shown in the movie “The Martian,” but the dust lofted by storms can still wreak havoc on people and machines, as well as reduce available solar energy. Recent studies indicate a big storm may be brewing during the next few months.

+ Get the full forecast

2. Where No Rover Has Gone Before

Our Opportunity Mars rover will drive down an ancient gully that may have been carved by liquid water. Several spacecraft at Mars have observed such channels from a distance, but this will be the first up-close exploration. Opportunity will also, for the first time, enter the interior of Endeavour Crater, where it has worked for the last five years. All this is part of a two-year extended mission that began Oct. 1, the latest in a series of extensions going back to the end of Opportunity’s prime mission in April 2004. Opportunity landed on Mars in January of that year, on a mission planned to last 90 Martian days (92.4 Earth days). More than 12 Earth years later, it’s still rolling.

+ Follow along + See other recent pictures from Endeavour Crater

3. An Uphill Climb

Opportunity isn’t the only NASA Mars rover getting a mission extension. On the other side of the planet, the Curiosity rover is driving and collecting samples amid some of the most scenic landscapes ever visited on Mars. Curiosity’s two-year mission extension also began Oct. 1. It’s driving toward uphill destinations, including a ridge capped with material rich in the iron-oxide mineral hematite, about a mile-and-a-half (two-and-a-half kilometers) ahead. Beyond that, there’s an exposure of clay-rich bedrock. These are key exploration sites on lower Mount Sharp, which is a layered, Mount-Rainier-size mound where Curiosity is investigating evidence of ancient, water-rich environments that contrast with the harsh, dry conditions on the surface of Mars today.

+ Learn more

4. Keep a Sharp Lookout

Meanwhile, the Mars Reconnaissance Orbiter continues its watch on the Red Planet from above. The mission team has just released a massive new collection of super-high-resolution images of the Martian surface.

+ Take a look

5. 20/20 Vision for the 2020 Rover

In the year 2020, Opportunity and Curiosity will be joined by a new mobile laboratory on Mars. In the past week, we tested new “eyes” for that mission. The Mars 2020 rover’s Lander Vision System helped guide the rocket to a precise landing at a predesignated target. The system can direct the craft toward a safe landing at its primary target site or divert touchdown toward better terrain if there are hazards in the approaching target area.

+ Get details

Discover the full list of 10 things to know about our solar system this week HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Solar System: Things to Know This Week

Mark your calendars for summer 2018: That’s when we’re launching a spacecraft to touch the sun. 

In honor of our first-ever mission to the heart of the solar system, this week we’re delving into the life and times of this powerful yellow dwarf star.

1. Meet Parker 

Parker Solar Probe, our first mission to go to the sun, is named after Eugene Parker, an American astrophysicist who first theorized that the sun constantly sends out a flow of particles and energy called the solar wind. This historic mission will explore one of the last regions of the solar system to be visited by a spacecraft and help scientists unlock answers to questions they’ve been pondering for more than five decades.

2. Extra SPF, Please 

Parker Solar Probe will swoop within 4 million miles of the sun’s surface, facing heat and radiation like no spacecraft before it. The mission will provide new data on solar activity to help us better understand our home star and its activity - information that can improve forecasts of major space-weather events that could impact life on Earth.

3. Majorly Massive 

The sun is the center of our solar system and makes up 99.8 percent of the mass of the entire solar system. If the sun were as tall as a typical front door, Earth would be about the size of a nickel.

4. Different Spin 

Since the sun is not a solid body, different parts of the sun rotate at different rates. At the equator, the sun spins once about every 25 days, but at its poles the sun rotates once on its axis every 36 Earth days.

5. Can’t Stand on It

The sun is a star and a star doesn’t have a solid surface. Rather, it’s a ball of ionized gas 92.1% hydrogen (H2) and 7.8% helium (He) held together by its own gravity.

6. Center of Attention 

The sun isn’t a planet, so it doesn’t have any moons. But, the sun is orbited by eight planets, at least five dwarf planets, tens of thousands of asteroids, and hundreds of thousands to trillions of comets and icy bodies.

7. It’s Hot in There 

And we mean really, really hot. The temperature at the sun’s core is about 27 million degrees Fahrenheit. However, its atmosphere, the corona, can reach temperatures of 3 million degrees. (That’s as if it got hotter the farther away you got from a fire, instead of cooler!) Parker Solar Probe will help scientists solve the mystery of why the corona’s temperature is so much higher than the surface.

8. Travel Conditions

The sun influences the entire solar system, so studying it helps us better understand the space weather that our astronauts and spacecraft travel through.

9. Life on the Sun? 

Better to admire from afar. Thanks to its hot, energetic mix of gases and plasma, the sun can’t be home to living things. However, we can thank the sun for making life on Earth possible by providing the warmth and energy that supply Earth’s food chain.

10. Chance of a Lifetime 

Last but not least, don’t forget that the first total solar eclipse to sweep across the U.S. from coast-to-coast since 1918 is happening on August 21, 2017. Our toolkit has you need to know to about it. 

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

Habe Mut, dich deines eigenen Verstandes zu bedienen.

Have the courage to use your own mind.

Immanuel Kant (1724 – 1804), German philosopher

(via jedentageinzitat)

The Van Allen Belt & the South Atlantic Anomaly

NASA’s first satellite, launched in 1958, discovered two giant swaths of radiation encircling Earth. Five decades later, scientists are still trying to unlock the mysteries of these phenomena known as the Van Allen belt. The belt is named after its discoverer, American astrophysicist James Van Allen.

The near-Earth space environment is a complex interaction between the planet’s magnetic field, cool plasma moving up from Earth’s ionosphere, and hotter plasma coming in from the solar wind. This dynamic region is populated by charged particles (electrons and ions) which occupy regions known as the plasmasphere and the Van Allen radiation belt. As solar wind and cosmic rays carry fast-moving, highly energized particles past Earth, some of these particles become trapped by the planet’s magnetic field. These particles carry a lot of energy, and it is important to mention their energies when describing the belt, because there are actually two distinct belts; one with energetic electrons forming the outer belt, and a combination of protons and electrons creating the inner belt. The resulting belts, can swell or shrink in size in response to incoming particles from Earth’s upper atmosphere and changes in the solar wind. Recent studies suggest that there is boundary at the inner edge of the outer belt at roughly 7,200 miles in altitude that appears to block the ultrafast electrons from breaching the invisible shield that protects Earth. 

Earth’s magnetic field doesn’t exactly line up with the planet’s rotation axis, the belts are actually tilted a bit. Because of this asymmetry, one of the shields that trap potentially harmful particles from space dips down to 200 km (124 mi) altitude.

This dip in the earth’s magnetic field allows charged particles and cosmic rays to reach lower into the atmosphere. Satellites and other low orbiting spacecraft passing through this region of space actually enter the Van Allen radiation belt and are bombarded by protons. Exposure to such radiation can wreak havoc on satellite electronics, and pose serious health risks to astronauts. This peculiar region is called the South Atlantic Anomaly.

Credit: NASA/ESA/M. Kornmesser