Space News/UFO's Etc...(Discussion/Pics/Vids)

[ilan]

50 Strange and Amazing Astronomy Facts

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1- Saturn would float if you would put it in water.
2- If you would place a pinhead sized piece of the Sun on the Earth you would die from standing within 145 km (90 miles) from it.
3- Space is not a complete vacuum, there are about 3 atoms per cubic meter of space.
4- Only 5% of the universe is made up of normal matter, 25% is dark matter and 70% is dark energy.
5- Neutron stars are so dense that a teaspoon of them would be equal to the weight of the entire Earth’s population.
6- The Sun is 400 times larger than the Moon but is 400 times further away from Earth making them appear the same size.
7- The star Lucy in the constellation Centaurus is a huge cosmic diamond of 10 billion trillion trillion carats.
8- Seasons last 21 years on Uranus while each pole has 42 years of sunlight followed by 42 years of darkness.
9- Venus,on the other hand, does not have any seasons at all.
10 -1 year on Mercury consists of less than 2 days on Mercury.
11- There are as many oxygen atoms in a breath as breaths of air in the atmosphere.
12- Helium is the only substance in the universe that cannot be in solid form.It can’t be cold enough.
13- The coldest place in the universe is on Earth. In Wolfgang Ketterles lab in Massachusetts. 0.000000000001 degrees Kelvin.
14- The pistol star is the most luminous star known 10 million times the brightness of the Sun.
15- Saturn’s moon Titan has liquid oceans of natural gas.
16- All the planets are the same age: 4.544 billion years.
17- Earths moon was most likely formed after an early planet named Theia crashed into Earth.
18- 8000 stars are visible with naked eye from Earth. 4000 in each hemisphere, 2000 at daylight and 2000 at night.
19- 90-99% of all normal matter in the universe is hydrogen.
20- Only 55% of all Americans knows that the Sun is a star.
21- Because of the speed the Sun moves at, solar eclipses can last at most 7 minutes and 58 seconds.
22- Lunar eclipses, however, can last 1 hour and 40 minutes.
23- All the coal, oil, gas, wood and fuel on Earth would only keep the Sun burning for few days.
24- A full moon is nine times brighter than a half moon.
25- When the Moon is directly above your head or if you stand at the equator, you weight slightly less.
26- A single Quasar produce the same amount of energy as 1 trillion suns.
27- Just after the Big Bang, everything in the universe was in liquid form.
28- A planet nicknamed “The Genesis Planet” has been found to be 12.7 billion years old making it the oldest planet found.
29- The shape of the universe looks a lot like a brain cell.
30- Every year, the Moon is moving away from Earth by 3.8 centimeters.
31- The Moon spins around its axis in the same time it goes one lap around the Earth which makes us always see the same side of it.
32- Upsilon Andromeda B also only face one side to its star. One side is hot as lava while the other one is cold below freezing.
33- The average galaxy contains “only” 40 billion stars.
34- While in space astronomers can get taller, but at the same time their hearts can get smaller.
35- Mars surface is cowered with iron oxide (rust).
36- Only half a billionth of the energy released by the Sun reaches Earth.
37- Rogue planets are not bound by any star, brown dwarf or another planet which makes them free-float around the galaxy.
38- Sweeps 10 is the planet with the shortest orbital period found. It orbits its star in only 10 hours.
39- 85% of all stars in our galaxy are part of multiple-star systems.
40- Some brown dwarfs have liquid iron rain falling down on them.
41- The light emitting from the Sun is actually 30.000 years old.
42- Of the over 20 million meteors that are observable every day only one or two reach the surface of Earth.
43- The United States have approximately 3.500 astronomers, but over 15.000 astrologers.
44- The closest black hole to Earth is only 1.600 light-years away.
45- There are at least 10^24 stars in the universe.
46- Certain “star quakes” have been found to tear apart the surface of neutron stars.
47- Any free-moving liquid in outer space will form itself into a sphere due to surface tension.
48- The odds of being killed by falling space debris is 1 in 5 billion.
49- Neutron stars can rotate up to 500 times in 1 second.
50- The largest structure found in the universe is the Sloan Great Wall, a super cluster of galaxies 1.37 billion light-years wide.

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[SIZE=2]https://astroceanomy.com/2011/03/04/50-amazing-and-strange-astronomy-facts/[/SIZE]
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[ilan]

Something below Jupiter's Great Red Spot whips up temperatures hotter than the rest of the planet
By Rebecca Boyle, Astronomy Magazine | Published: Wednesday, July 27, 2016

For decades, the mystery has kept researchers scratching their heads. Now, we may find an answer.

NASA / ESA / HST
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Talk about extreme weather. The solar system’s biggest and baddest storm, Jupiter’s Great Red Spot, is so loud and violent that it heats up the giant planet’s atmosphere. Above the storm, which has been raging for at least 300 years, the atmosphere is hundreds of degrees hotter than anywhere else on Jupiter. The warmth comes from within, according to a paper published in Nature today.

Orbiting hundreds of millions of miles from the sun, Jupiter is about three times toastier than it’s expected to be without some extra source of warmth. Sunlight at Jupiter is 25 times dimmer than it is at Earth, which means the sun can’t be enough to warm the planet’s atmosphere to the temperatures scientists have measured. Jupiter has powerful auroras at its poles, and they can create electrical storms that heat the atmosphere. But their warmth would mostly stay trapped at higher latitudes, thanks to the Coriolis effect on a fast-spinning world (Jupiter’s day is just shy of 10 hours long). So that can’t explain it, either.

“This warmth is a discrepancy that has haunted everyone for 50 years now,” says James O’Donoghue, a planetary scientist at Boston University.

To figure it out, he studied the Great Red Spot in great detail using the 3-meter NASA Infrared Telescope Facility at the Mauna Kea Observatory. A spectrometer split up the light Jupiter reflects, which allowed him to scrutinize Jupiter’s howling winds. He and colleagues think the atmosphere’s own turbulence may be heating things up.

While the Great Red Spot twists and rages, it causes turbulent flows of gas in Jupiter’s upper atmosphere. The turbulence causes two types of waves to form: gravity waves and high-frequency acoustic waves. Gravity waves are akin to the vibrations of a guitar string when it’s plucked. Acoustic waves are compressions of the air, just like any other sound. About 500 miles above the spot, these waves collide and release energy, like ocean waves crashing on a shoreline.

“It’s not thunder heating, which I would have loved to be able to say,” O’Donoghue says. “It’s kind of the same as sound waves, but I don’t think thunder is a good analogy, because we don’t know about the lightning.”

No one has ever seen lightning at Jupiter's Great Red Spot, although it could just be deep within the planet and invisible to us, he adds.

O’Donoghue measured above and around the Great Red Spot, and didn’t find any extra sources of heat. That means it must be coming from underneath the storm, he says. As it turns out, the source is something Jupiter has in common with Earth, where atmospheric turbulence can also heat things up.

On Earth, tsunami, volcanoes, storms and earthquakes can all shake up the atmosphere and warm it, by generating high-frequency acoustic waves that get stronger as they move higher into the atmosphere. Even passive mountains can do this. Erratic wind gusts blowing over bumpy terrain can create hotspots, sometimes hundreds of degrees warmer than the air a few miles away. Jupiter doesn’t have mountains, but it has enough internal turbulence -- especially in the Great Red Spot -- to create the same types of waves.

 

[ilan]

How to see the Delta Aquariid meteor shower
By Richard Talcott, Astronomy Magazine | Published: Thursday, July 28, 2016

Head out under a clear, dark sky after midnight these next couple of nights and you’ll see a dramatic display of “shooting stars.”

Mike Lewinski / Flickr
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The early morning hours of late July provide one of nature’s annual treats: the Southern Delta Aquariid meteor shower. The shower peaks the night of July 29/30, but it typically produces just as many meteors a day or two on either side. Observers under a dark sky can expect to see between 15 and 20 “shooting stars” per hour during the prime viewing hours after midnight.

The streaks of light appear to radiate from a point near the 3rd-magnitude star Delta (d) Aquarii, which rises in late evening and climbs highest in the south around 3 a.m. local daylight time. But don’t stare directly at the radiant. Although the meteors appear to emanate from this spot, any you see there will appear as just a point of light. All other things being equal, the farther away from the radiant a meteor lies, the longer its trail will be.

For the best views, look about two-thirds of the way from the horizon to the zenith. But don’t get tunnel vision gazing at one location. Let your eyes wander so your peripheral vision can pick up meteors you otherwise might not see. Keep comfortable by reclining in a lawn chair or lying on an air mattress. And bring along a sweater or light jacket. Even if evening temperatures are comfortable, you won’t be active and can get chilled in a hurry.

You’ll also see more meteors if you observe under a dark sky. Leave your city or suburban backyard behind and head out to the country. If you can’t get away, at least find a large park with plenty of trees to block the lights. Fortunately, the Moon is a waning crescent at the shower’s peak and won’t pose add much natural light pollution.

 

[ilan]

Tour August’s Sky: Perseids & Planets Aplenty
By: The Editors of Sky Telescope | July 28, 2016

Download or play Sky & Telescope's astronomy podcast, and you'll get a guided tour of the night sky. In early evening look for Mars and Saturn embedded in Scorpius toward south, and key an eye out for Perseid meteors.
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Ask a skywatcher what’s special about August, and the response will likely be the Perseid meteor shower. These “shooting stars” are caused when little bits of grit shed by a comet called Swift-Tuttle slam into our atmosphere. Every August, we plow right through this stream of dusty debris. The shower should reach its peak late on Thursday night, August 11th, and Wednesday morning, the 12th.

During August, the positions of Mars and Saurn change with respect that of Antares and the stars of Scorpius. Sky & Telescope diagram

While you’re waiting for the Perseids to show up, look toward south for a trio of stars in the shape of a triangle. Its very bright right corner is anchored by Mars. To its upper right is Saturn, and below that, the dimmest of the three, is the only true star: Antares, the heart of the constellation Scorpius. Mars moves eastward quite a bit this month, and by month’s end the triangle collapses to a line.

For more tips on what to see in the night sky during August, listen to (or download) our monthly astronomy podcast below.

http://media.blubrry.com/skytourpodcasts/p/www.skyandtelescope.com/wp-content/uploads/SkyTour-August-2016.mp3

 

[ilan]

Chorus of black holes radiates X-rays
California Institute of Technology | July 28, 2016
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The NuSTAR mission is identifying which black holes erupt with the highest-energy X-rays, report scientists. The results will ultimately help astronomers understand how the growth patterns of supermassive black holes change over time, a key factor in the development of black holes and the galaxies that host them.

The blue dots in this field of galaxies, known as the COSMOS field, show galaxies that contain supermassive black holes emitting high-energy X-rays. They were detected by NASA's Nuclear Spectroscopic Array, or NuSTAR, which spotted 32 such black holes in this field and has observed hundreds across the whole sky so far. The other colored dots are galaxies that host black holes emitting lower-energy X-rays, and were spotted by NASA's Chandra X-ray Observatory. Chandra data show X-rays with energies between 0.5 to 7 kiloelectron volts, while NuSTAR data show X-rays between 8 to 24 kiloelectron volts. Credit: NASA/JPL-Caltech

The blue dots in this field of galaxies, known as the COSMOS field, show galaxies that contain supermassive black holes emitting high-energy X-rays. They were detected by NASA's Nuclear Spectroscopic Array, or NuSTAR, which spotted 32 such black holes in this field and has observed hundreds across the whole sky so far. The other colored dots are galaxies that host black holes emitting lower-energy X-rays, and were spotted by NASA's Chandra X-ray Observatory. Chandra data show X-rays with energies between 0.5 to 7 kiloelectron volts, while NuSTAR data show X-rays between 8 to 24 kiloelectron volts.

Supermassive black holes do not give off any of their own light, hence the word "black" in their name. However, many black holes pull in, or accrete, surrounding material, and emit powerful bursts of X-rays. Collectively, these active black holes throughout the sky can be thought of a cosmic choir, singing in the language of X-rays. Their "song" is what astronomers call the cosmic X-ray background.

To date, NASA's Chandra mission has managed to pinpoint many of the individual black holes contributing to the X-ray background, but the ones that let out high-energy X-rays--those with the highest-pitched "voices"--have remained elusive.

New data from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, has, for the first time, begun to pinpoint large numbers of the black holes sending out the high-energy X-rays. More technically, NuSTAR has made significant progress in resolving the high-energy X-ray background.

"We've gone from resolving just 2 percent of the high-energy X-ray background to 35 percent," says Fiona Harrison, Benjamin M. Rosen Professor of Physics and Astronomy at Caltech, the principal investigator of NuSTAR, and lead author of a new study describing the findings in an upcoming issue of The Astrophysical Journal. "We can see the most obscured black holes, hidden in thick gas and dust."

The results will ultimately help astronomers understand how the growth patterns of supermassive black holes change over time--a key factor in the development of black holes and the galaxies that host them. For instance, the supermassive black hole at the center of our Milky Way galaxy is dormant now, but at some point in the past, it would have siphoned gas and bulked up in size.

As black holes grow, their intense gravity pulls matter toward them. The matter heats up to extremely high temperatures and particles get boosted to close to the speed of light. Together, these processes make the black hole surroundings glow with X-rays. A supermassive black hole with an ample supply of fuel, or gas, will give off more high-energy X-rays.

NuSTAR is the first telescope capable of focusing these high-energy X-rays into sharp pictures.

"Before NuSTAR, the X-ray background in high-energies was just one blur with no resolved sources," says Harrison. "To untangle what's going on, you have to pinpoint and count up the individual sources of the X-rays."

"We knew this cosmic choir had a strong high-pitched component, but we still don't know if it comes from a lot of smaller, quiet singers, or a few with loud voices," says coauthor Daniel Stern, the project scientist for NuSTAR at JPL. "Now, thanks to NuSTAR, we're gaining a better understanding of the black holes and starting to address these questions."

High-energy X-rays can reveal what lies around the most obscured supermassive black holes, which are otherwise hard to see. In the same way that medical X-rays can travel through your skin to reveal pictures of bones, NuSTAR can see through the gas and dust around black holes, to get a deeper view of what is going on inside.

With NuSTAR's more complete picture of supermassive black hole populations, astronomers can begin to puzzle together how these objects evolve and change over time. When did they start and stop growing? What is the distribution of the gas and dust that both feed and hide the black holes?

The team expects that over time, NuSTAR will be able to resolve more of the high-energy X-ray background--and better decipher the X-ray song of the universe's black holes.

 

[ilan]

Tonight, explore the Big Dipper
By Deborah Byrd in Tonight | August 1, 2016
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Tonight, notice the two outer stars in the bowl of the Big Dipper – Dubhe and Merak. They always point to Polaris, the North Star. To find the Dipper at this time of year, look toward the northwest in the evening. Once you’ve found it – after locating Polaris – look more carefully at the second star from the end of the Big Dipper’s handle. If your sky is dark enough, and your eyesight is good, you’ll see that this star, Mizar, has a nearby companion, called Alcor.

Arabian stargazers referred to Mizar and Alcor as the “horse and rider.” These stars are a good test of the night’s viewing conditions: if you can’t see Alcor, there might be thin clouds up there.

These two stars are what’s called “naked-eye double star,” appearing double from our earthly vantage point. But do they orbit each other? Astronomers aren’t sure. The distances to these stars (as to most stars) aren’t precisely known. If Mizar and Alcor make up a true binary star, it’s a very wide one. If they do lie at the same distance from Earth, their separation is 0.27 light-years … that’s in contrast to eight light-minutes for Earth’s distance from our sun … or several light-hours for the distance to our sun of the most distant worlds in our solar system. Still, it’s possible that Mizar and Alcor could be this far apart and still be orbiting one another, with a very long orbital period of three-quarters of a million years.

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Big Dipper before dawn in late June, 2015, by Hope Carter.
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Bottom line: Use the Big Dipper to find Polaris, the North Star. Also, notice the two stars Mizar and Alcor in the Big Dipper’s handle.

 

[Capt.Kangaroo]

A Rocket Booster Falls Back to Earth

https://youtu.be/9nPLmydWacE

What's that crossing the sky? Although it looked a bit like a large meteor, it was actually the booster of a Chinese rocket returning to Earth after its launch two days earlier. On the night of July 27, the rocket component heated up and broke up into glowing pieces as it re-entered Earth's atmosphere. The path of the falling booster took it over several US states, moving west to east, from California to Utah. Space debris can usually be distinguished from meteors by its slow speed and expansive break up. The featured video was taken in front of the Provo City Library in Utah, which was coincidently occupied by over 100 people -- many with smartphones already out of their pockets playing Pokémon GO.

Video Credit & Copyright: Matthew Holt

 

[ilan]

No, Asteroid Bennu Won't Destroy Earth
By Mike Wall, Space.com Senior Writer | August 1, 2016 06:52pm ET

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The mapping of the near-Earth asteroid Bennu is one of the science goals of NASA's OSIRIS-REx mission, and an integral part of spacecraft operations. The spacecraft will spend a year surveying Bennu before collecting a sample that will be returned to Earth for analysis. Credit: NASA/Goddard/University of Arizona

The mapping of the near-Earth asteroid Bennu is one of the science goals of NASA's OSIRIS-REx mission, and an integral part of spacecraft operations. The spacecraft will spend a year surveying Bennu before collecting a sample that will be returned to Earth for analysis.
Credit: NASA/Goddard/University of Arizona

NASA's new asteroid-sampling mission will do a lot of interesting things, but helping prepare humanity for Earth's imminent destruction is not among them.

There is indeed a chance that the 1,650-foot-wide (500 meters) asteroid Bennu — the target of NASA's OSIRIS-REx spacecraft, which is scheduled to launch next month — could hit Earth late in the 22nd century.

But, mission officials stressed, that chance is slim, and the space rock is not nearly big enough to pose an existential threat to the planet, despite what some media reports claimed over the weekend. [Potentially Dangerous Asteroids (Images)]

"We're not talking about an asteroid that could destroy the Earth," OSIRIS-REx principal investigator Dante Lauretta, of the Lunar and Planetary Laboratory at the University of Arizona, told Space.com. "We're not anywhere near that kind of energy for an impact."

Sampling an asteroid

If all goes according to plan, the $800 million OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer) mission will lift off atop a United Launch Alliance Atlas V rocket from Florida's Cape Canaveral Air Force Station on Sept. 8.

The spacecraft will spend two years chasing Bennu down, finally rendezvousing with the near-Earth asteroid in August 2018. OSIRIS-REx will then study the space rock from orbit for another two years before grabbing at least 2.1 ounces (60 grams) of surface material in July 2020.

In 2023, this relatively hefty sample should make it back to Earth, where researchers in laboratories around the globe will analyze the material in a number of ways.

The mission team is chiefly interested in learning the role that asteroids like Bennu — dark, primitive and apparently carbon-rich objects — may have played in helping life get a foothold on Earth, Lauretta said.

"Did these kinds of bodies deliver organic material and water, in the form of hydrated minerals like clays, to the surface of our planet that created the habitability and the environments that may have led to the origin of life?" Lauretta said.

"That's the prime mission," to investigate that question, he added.

There are secondary objectives as well, including learning more about the valuable resources that Bennu-like asteroids may harbor, Lauretta said. And then there's the planetary-defense angle, which has gotten a lot of attention in the last few days.

A potentially hazardous asteroid

Bennu is officially classified as a potentially dangerous asteroid. In fact, there's an 0.037 percent (or 1-in-2,700) chance that it will strike Earth in the last quarter of the 22nd century, NASA scientists have calculated.

Specifically, that's the probability that, during an Earthy flyby in 2135, Bennu will hit a special orbit-altering "keyhole" that will send it on a collision course with the planet later in the century.

OSIRIS-REx will help scientists refine those odds, by refining their understanding of Bennu's orbit. (That orbit, by the way, is already the best-known of any asteroid, Lauretta said; thanks to extensive observations since Bennu's 1999 discovery, astronomers have nailed the space rock's orbital radius down to within 20 feet, or 6 m.)

"Our uncertainties will shrink, so that will allow us to recalculate the impact probability," Lauretta said. "We don't know which direction it'll go. It could go down, because we just eliminated a bunch of possible keyholes that Bennu may hit. Or it may go up, because in the area that's left we have a higher concentration of keyholes compared to the overall area of the uncertainty plane."

OSIRIS-REx's work will also help researchers better understand the Yarkovsky effect, which describes how absorbed sunlight, when radiated away as heat, affects an object's trajectory. Such information will improve knowledge not only of where Bennu is headed, but where it came from, Lauretta said.

But to focus on where it's headed — what if Bennu does hit one of those keyholes in 2135, and the space rock squares Earth up for an impact in 2185 or thereabouts? What should humanity expect?

Such an impact would likely devastate the local area but fall short of wiping out civilization or causing a mass extinction, experts have said. Astronomers estimate that a space rock must be at least 0.6 miles (1 kilometer) wide to cause a global catastrophe. (For perspective: The asteroid thought to have wiped out the dinosaurs — or at least to have finished them off — was probably about 6 miles, or 10 km, across.)

But an impact would not be inevitable, even if Bennu had Earth in its sights. Given a decade or so worth of lead time, researchers say, an incoming asteroid could potentially be nudged off course using fly-along "gravity tractor" probes and/or "kinetic impactors." And if time is not on humanity's side, there's always the nuclear option.

See related video:

http://www.space.com/33616-asteroid-bennu-will-not-destroy-earth.html#ooid=A0cnk4MzE6JNiwIKj0Fjj8yhO_7FiO3B

 

[Kimbo]

"That is the sound of inevitability" - Agent Smith

 

[ilan]

Well, at least none of us will be around in 2185 if it does happen!

 

[Kimbo]

Well i was hoping they would freeze me and wake me up in a thousand years ...so much for that idea!!

Well, at least none of us will be around in 2185 if it does happen!

 

[ilan]

It'll be kind of like Idiocracy. (I really liked that movie...dumb but fun and the direction we're actually heading.)

http://www.imdb.com/title/tt0387808/

 

[Kimbo]

You are the fifth person that has told me that, I will have to check the movie!!

 

[ilan]

Astronomers found a large void of young stars in the Milky Way
Jordan Rice, Astronomy Magazine | Tuesday, August 02, 2016

There lies an abundance of older stars and less younger stars at the center of the Milky Way, but a new study has found that there are even less juvenile stars than previously thought.

An artist's interpretation of the distribution of young stars shown by Cepheid Variable stars in blue. Besides a small clump in the center of the galaxy, for 8,000 light-years around the center, their exist virtually no Cepheids. University of Tokyo ​

A team of Japanese, South African, and Italian astronomers have found that there is a massive region around the center of the Milky Way that is devoid of young stars. The research was published in the Monthly Notices of the Royal Astronomical Society.
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There exist billions of stars in the Milky Way, a spiral galaxy, with the Sun approximately 26,000 light-years from the center in one of its spiral arms. Measuring the distribution of stars within the galaxy is very important in understanding how our galaxy formed and evolved.

Young, pulsating stars called Cepheid Variable stars, or Cepheids for short, are the perfect candidate for this. They are between 10 and 300 million years old, younger than our Sun at 4.6 billion years old, and pulsate in their brightness in a repeating cycle. As this pulsation time is related to its luminosity, astronomers can monitor them to determine their actual brightness; after comparing this with the brightness as seen from Earth, a distance can be determined.

Finding these stars is difficult as the center of the galaxy is full of interstellar dust that obscures the light and hides many stars from view. Using near-infrared observations from the South African Large Telescope (SALT), the team was able to see past the dust; to their surprise they found hardly and Cepheids around a region about 1,000 light-years wide from the core of the galaxy.

“We already found some time ago that there are Cepheids in the central heart of our Milky Way (in a region about 150 light-years in radius),” says Noriyuki Matsunaga, lead author from the University of Tokyo, in a press release. “Now we find that outside this there is a huge Cepheid desert extending out to 8,000 light-years from the centre.”

These findings suggest that the extreme inner disk has virtually no young stars. “Our conclusions are contrary to other recent work, but in line with the work of radio astronomers who see no new stars being born in this desert,” says Michael Feast, a co-author of the study, in a press release.

The results suggest that no significant amount of star formation has occurred in this area for hundreds of millions of years says another co-author, Giuseppe Bono. The chemical makeup and movement of the Cepheid Variable stars are guiding the team in understanding the formation of the galaxy.

Mostly Cepheids have been used to measure distances of objects in far off in the universe, but this new study shows that the same technique can be used in revealing information a lot closer to home.

 

[ilan]

Keck Observatory measures oxygen in galaxy 12 billion years ago
W. M. Keck Observatory Press Release
Astronomy Now | 4 August 2016
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Galaxy COSMOS-1908 is in the centre of this NASA/ESA Hubble Space Telescope image, indicated by the arrow. Nearly everything in the image is a galaxy. Image credit: Ryan Sanders and the CANDELS team.

UCLA astronomers have used the W. M. Keck Observatory on Maunakea, Hawaii, to make the first accurate measurement of the abundance of oxygen in a distant galaxy. Oxygen, the third-most abundant chemical element in the universe, is created inside stars and released into interstellar gas when stars die. Quantifying the amount of oxygen is key to understanding how matter cycles in and out of galaxies. This research is published online in the Astrophysical Journal Letters.

“This is by far the most distant galaxy for which the oxygen abundance has actually been measured,” said Alice Shapley, a UCLA professor of astronomy, and co-author of the study. “We’re looking back in time at this galaxy as it appeared 12 billion years ago.”

Knowing the abundance of oxygen in the galaxy called COSMOS-1908 is an important stepping stone toward allowing astronomers to better understand the population of faint, distant galaxies observed when the universe was only a few billion years old, Shapley said.

COSMOS-1908 contains approximately one billion stars. In contrast, the Milky Way contains approximately 100 billion stars. Furthermore, COSMOS-1908 contains approximately only 20 percent the abundance of oxygen that is observed in the Sun.

Typically, astronomers rely on extremely indirect and imprecise techniques for estimating oxygen abundance for the vast majority of distant galaxies. But in this case, UCLA researchers used a direct measurement, said Ryan Sanders, astronomy graduate student and the study’s lead author.

“Close galaxies are much brighter, and we have a very good method of determining the amount of oxygen in nearby galaxies,” Sanders said.

In faint, distant galaxies, the task is dramatically more difficult, but COSMOS-1908 was one case for which Sanders was able to apply the “robust” method commonly applied to nearby galaxies. “We hope this will be the first of many,” he said.

Shapley said that prior to Sanders’ discovery, researchers didn’t know if they could measure how much oxygen there was in these distant galaxies.

“Ryan’s discovery shows we can measure the oxygen and compare these observations with models of how galaxies form and what their history of star formation is,” Shapley said.

 

[ilan]

Perseid meteor shower set for its best show in nearly 20 years
By Richard Talcott, Astronomy Magazine | Published: Friday, August 5, 2016

You can expect to see up to 150 'shooting stars' per hour when 2016’s best meteor shower peaks the night of August 11/12.
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If you ask most skygazers to name their favorite meteor shower, the odds are good that “Perseid” will be the first word out of their mouths. This annual shower seemingly has it all: It offers a consistently high rate of meteors year after year; it produces a higher percentage of bright ones than most other showers; it occurs in August when many people take summer vacation; and it happens at a time when nice weather and reasonable nighttime temperatures are common north of the equator. No other major shower boasts all four of these attributes.

In a typical year, observers under a clear dark sky can expect to see up to 100 meteors per hour. Astronomers think we may be in for an even better show this year, however. The Perseids begin as tiny specks of dust that hit Earth’s atmosphere at 37 miles per second, vaporizing from friction with the air and leaving behind the streaks of light we call meteors. These dust particles were born in a periodic comet known as 109P/Swift-Tuttle, which last returned to the inner solar system in 1992. But the giant planet Jupiter recently nudged Swift-Tuttle’s debris stream closer to Earth’s orbit. If predictions hold true, we could see up to 150 meteors per hour the night of August 11/12.

The best views will come in the predawn hours of Friday morning the 12th, after the waxing gibbous Moon sets around 1 a.m. local daylight time. The spectacle will continue to improve as dawn approaches because the shower’s radiant — the spot on the border between the constellations Perseus and Cassiopeia where the meteors appear to emanate from — climbs higher.

As always, you’ll see more meteors at a viewing site far from any artificial lights. Look about two-thirds of the way from the horizon to the zenith, but don’t get tunnel vision gazing at one location. Let your eyes wander so your peripheral vision can pick up meteors you otherwise might not see. Keep comfortable by reclining in a lawn chair or lying on an air mattress. And bring along a sweater or light jacket. Even if evening temperatures are comfortable, you won’t be active and can get chilled in a hurry.

 

[ilan]

Moon near star Spica on August 8
By Bruce McClure in Tonight, Earth & Sky | August 8, 2016
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Tonight – August 8, 2016 – look low in the southwestern sky for the rather wide waxing crescent moon and the star Spica, the brightest star in the constellation Virgo the Maiden. Don’t wait too late to look for them, for the two will follow the sun beneath the horizon by early-to-mid evening.

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Over the next several days days, at nightfall, watch for the moon to move away from Spica and toward the planets Mars and Saturn.

As evening falls on August 10, 11 and 12, the waxing gibbous moon will be shining near planets Mars and Saturn, and the star Antares. The green line depicts the ecliptic – the sun’s yearly path and the moon’s monthly path in front of the constellations of the zodiac.

As evening falls on August 10, 11 and 12, the waxing gibbous moon will be shining near planets Mars and Saturn, and the star Antares. The green line depicts the ecliptic - the sun's yearly path and the moon's monthly path in front of the constellations of the zodiac.

Spica is around 250 light-years from Earth. For this star to shine at 1st-magnitude brightness at this distance must mean this star in intrinsically very luminous indeed. This blue-white gem of a star is thought to be some 1,900 times more luminous than our sun. Read more about the true brightnesses of stars.

Although Spica looks like a single point of light to the eye, it’s actually two stars in one. According to astronomer Jim Kaler, these two component stars are only 0.12 of an astronomical unit apart (0.12 the Earth-sun distance). The two stars in the Spica system revolve around each other in only four days.

Each day, the sun moves eastward along the ecliptic, getting closer and closer to Spica on the sky’s dome. Another way of looking at, Spica is sinking closer and closer to the glare of sunset daily. By mid-October, the sun will meet up with Spica in the constellation Virgo, at which time Spica will rise with the sun, cross the sky with the sun and set with the sun.

If you could see the stars during the daytime, you’d see the noonday sun and Spica crossing the meridian together every year around mid-October.

Spica’s yearly disappearance at evening dusk is a sure sign of the change of seasons, of summer giving way to autumn in the Northern Hemisphere – or of winter giving way to spring in the Southern Hemisphere. The first day that a star is no longer visible in the evening sky is called the heliacal setting of a star. After its heliacal setting, a star remains lost in the sun’s glare until the sun travels far enough east of the star to allow it to reappear in the east at morning dawn. The star’s first appearance in the morning sky is called its heliacal rising.

Bottom line: As darkness falls on August 8, 2016, watch for the waxing crescent moon to pair up with Spica in the constellation Virgo.

 

[Marley]

There Will Be A Gorgeous Meteor Shower This Week

http://www.msn.com/en-us/weather/topstories/there-will-be-a-gorgeous-meteor-shower-this-week/ar-BBvow5w

 

[ilan]

UFO Torments St. Louis Sparking Frenzied Debate Over Space Aliens (Video)
Sputnik International | 8 August 2016

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The video was shot from a camera at Malcolm W. Martin Memorial Park in St. Louis where a similar UFO was spotted in broad daylight only three weeks ago.

A mysterious brightly lit object hovering over the famous St. Louis arch recorded at Malcolm W. Martin Memorial Park and posted on Facebook has sparked a fierce debate on the internet about whether alien life has finally been observed or what else could explain the strange illuminated flying object.

The poster of the UFO footage, Malcolm W. Memorial Park, says "We guarantee you will be perplexed if you watch all 5 minutes of this surveillance footage!" The video has been viewed 787,000 times.

Explanations for the light on Facebook include a drone with a unidirectional light while others question whether a drone could produce such an enormous amount of light. Others speculate that the image may be a weather balloon although the speed of the growing object renders this theory unlikely. Perhaps, very simply, it was simply an insect flying by whose wings were illuminated and that appeared larger than normal in a security camera.

​Yet, this is not the first time that a UFO has been spotted near the St. Louis arch. Video from the same camera at Malcolm W. Martin Memorial Park also captured an unexplained object that appeared in broad daylight on July 14 2016.

Earlier this year, video of another mysterious object was observed near a military base in Dayton, Ohio setting the internet abuzz with run-of-the-mill assertions that it may be testing of a new top secret aerial vehicle to conspiracy theories that the US Air Force is in league with space aliens in a bid to overcome the aviation advances made Russia and China.

Last month, the world was also treated to a strange, apparently burning object spotted in the sky over parts of the Western US which was later determined to be a Chinese rocket burning upon reentry into the Earth’s atmosphere – a reasonable explanation that is nonetheless not much less disquieting than an invasion by little green men.

One thing is certain, Malcolm W. Martin Memorial Park is having fun stoking the conspiracy theories about UFOs and it may just pay off for the city of St. Louis perhaps spawning a new herd of UFO sightseers wondering if there is something else off in the great unknown.

See the video here:

https://www.youtube.com/watch?v=ehzVYFSdVMs&feature=youtu.be

 

[ilan]

What are Magnetars?
Fraser Cain, Universe Today | Article Updated: 9 Aug , 2016

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In a previous article, we crushed that idea that the Universe is perfect for life. It’s not. Almost the entire Universe is a horrible and hostile place, apart from a fraction of a mostly harmless planet in a backwater corner of the Milky Way.

While living here on Earth takes about 80 years to kill you, there are other places in the Universe at the very other end of the spectrum. Places that would kill you in a fraction of a fraction of a second. And nothing is more lethal than supernovae and remnants they leave behind: neutron stars.

We’ve done a few articles about neutron stars and their different flavours, so there should be some familiar terrain here.

Artist concept of a neutron star. Credit: NASA

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As you know, neutron stars are formed when stars more massive than our Sun explode as supernovae. When these stars die, they no longer have the light pressure pushing outward to counteract the massive gravity pulling inward.

This enormous inward force is so strong that it overcomes the repulsive force that keeps atoms from collapsing. Protons and electrons are forced into the same space, becoming neutrons. The whole thing is just made of neutrons. Did the star have hydrogen, helium, carbon and iron before? That’s too bad, because now it’s all neutrons.

You get pulsars when neutron stars first form. When all that former star is compressed into a teeny tiny package. The conservation of angular motion spins the star up to tremendous velocities, sometimes hundreds of times a second.

But when neutron stars form, about one in ten does something really really strange, becoming one of the most mysterious and terrifying objects in the Universe. They become magnetars. You’ve probably heard the name, but what are they?

As I said, magnetars are neutron stars, formed from supernovae. But something unusual happens as they form, spinning up their magnetic field to an intense level. In fact, astronomers aren’t exactly sure what happens to make them so strong.

This artist’s impression shows the magnetar in the very rich and young star cluster Westerlund 1
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One idea is that if you get the spin, temperature and magnetic field of a neutron star into a perfect sweet spot, it sets off a dynamo mechanism that amplifies the magnetic field by a factor of a thousand.

But a more recent discovery gives a tantalizing clue for how they form. Astronomers discovered a rogue magnetar on an escape trajectory out of the Milky Way. We’ve seen stars like this, and they’re ejected when one star in a binary system detonates as a supernova. In other words, this magnetar used to be part of a binary pair.

And while they were partners, the two stars orbited one another closer than the Earth orbits the Sun. This close, they could transfer material back and forth. The larger star began to die first, puffing out and transferring material to the smaller star. This increased mass spun the smaller star up to the point that it grew larger and spewed material back at the first star.

The initially smaller star detonated as a supernova first, ejecting the other star into this escape trajectory, and then the second went off, but instead of forming a regular neutron star, all these binary interactions turned it into a magnetar. There you go, mystery maybe solved?

The strength of the magnetic field around a magnetar completely boggles the imagination. The magnetic field of the Earth’s core is about 25 gauss, and here on the surface, we experience less than half a gauss. A regular bar magnet is about 100 gauss. Just a regular neutron star has a magnetic field of a trillion gauss. Magnetars are 1,000 times more powerful than that, with a magnetic field of a quadrillion gauss.

What if you could get close to a magnetar? Well, within about 1,000 kilometers of a magnetar, the magnetic field is so strong it messes with the electrons in your atoms. You would literally be torn apart at an atomic level. Even the atoms themselves are deformed into rod-like shapes, no longer usable by your precious life’s chemistry.

But you wouldn’t notice because you’d already be dead from the intense radiation streaming from the magnetar, and all the lethal particles orbiting the star and trapped in its magnetic field.

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Artist’s conception of a starquake cracking the surface of a neutron star. Credit: Darlene McElroy of LANL

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One of the most fascinating aspects of magnetars is how they can have starquakes. You know, earthquakes, but on stars… starquakes. When neutron stars form, they can have a delicious murder crust on the outside, surrounding the degenerate death matter inside. This crust of neutrons can crack, like the tectonic plates on Earth. As this happens, the magnetar releases a blast of radiation that we can see clear across the Milky Way.

In fact, the most powerful starquake ever recorded came from a magnetar called SGR 1806-20, located about 50,000 light years away. In a tenth of a second, one of these starquakes released more energy than the Sun gives off in 100,000 years. And this wasn’t even a supernova, it was merely a crack on the magnetar’s surface.

Magnetars are awesome, and provide the absolute opposite end of the spectrum for a safe and habitable Universe. Fortunately, they’re really far away and you won’t have to worry about them ever getting close.

Podcast:

http://archive.org/download/guidetospace/260WhatAreMagnetars.mp4