What do you do to relax in stressing situations?
Today, June 30 is International Asteroid Day. Here are some things to know about our fascinating space rubble.
Asteroids—named by British astronomer William Herschel from the Greek expression meaning "star-like"—are rocky, airless worlds that are too small to be called planets. But what they might lack in size they certainly make up for in number: An estimated 1.1 to 1.9 million asteroids larger than 1 kilometer are in the Main Belt between the orbits of Mars and Jupiter. And there are millions more that are smaller in size. Asteroids range in size from Vesta—the largest at about 329 miles (529 kilometers) wide—to bodies that are just a few feet across.
Asteroids are generally categorized into three types: carbon-rich, silicate, or metallic, or some combination of the three. Why the different types? It all comes down to how far from the sun they formed. Some experienced high temperatures and partly melted, with iron sinking to the center and volcanic lava forced to the surface. The asteroid Vesta is one example we know of today.
If all of the asteroids were combined into a ball, they would still be much smaller than the Earth's moon.
In 1801, Giuseppe Piazzi discovered the first and then-largest asteroid, Ceres, orbiting between Mars and Jupiter. Ceres is so large that it encompasses about one-fourth of the estimated total mass of all the asteroids in the asteroid belt. In 2006, its classification changed from asteroid to as a dwarf planet.
NASA's Psyche mission will launch in 2022 to explore an all-metal asteroid—what could be the core of an early planet—for the very first time. And in October 2021, the Lucy mission will be the first to visit Jupiter's swarms of Trojan asteroids.
The term 'near' in near-Earth asteroid is actually a misnomer; most of these bodies do not come close to Earth at all. By definition, a near-Earth asteroid is an asteroid that comes within 28 million miles (44 million km) of Earth's orbit. As of June 19, 2017, there are 16,209 known near-Earth asteroids, with 1,803 classified as potentially hazardous asteroids (those that could someday pose a threat to Earth).
About once a year, a car-sized asteroid hits Earth's atmosphere, creates an impressive fireball, and burns up before reaching the surface.
Ground-based observatories and facilities such as Pan-STARRS, the Catalina Sky Survey, and ATLAS are constantly on the hunt to detect near-Earth asteroids. NASA also has a small infrared observatory in orbit about the Earth: NEOWISE. In addition to detecting asteroids and comets, NEOWISE also characterizes these small bodies.
Roughly one-sixth of the asteroid population have a small companion moon (some even have two moons). The first discovery of an asteroid-moon system was of asteroid Ida and its moon Dactyl in 1993.
Several NASA space missions have flown to and observed asteroids. The NEAR Shoemaker mission landed on asteroid Eros in 2001 and NASA's Dawn mission was the first mission to orbit an asteroid in 2011. In 2005, the Japanese spacecraft Hayabusa landed on asteroid Itokawa. Currently, NASA's OSIRIS-REx is en route to a near-Earth asteroid called Bennu; it will bring a small sample back to Earth for study.
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This month binoculars will come in handy--to view the moon, star clusters, and a close pairing of Venus and Jupiter.
You can’t miss bright Venus in the predawn sky. This month Venus pairs up with Jupiter on the morning of November 13th.
The Leonids peak on a moonless November 17th. Expect no more than 10 meteors an hour around 3:00 a.m., the height of the shower.
The Northern and Southern sub-branches of the Taurid meteor shower offer sparse counts of about 5 meteors per hour, but slow, bright meteors are common.
The nearby November Orionids peak on the 28th. In contrast to the Taurids, the Orionids are swift. But don’t expect more than 3 meteors per hour.
The moon glides by three beautiful star clusters in the morning sky this month, and a pair of binoculars will allow you to see the individual stars in the clusters. Aim your binoculars at the Pleiades and the moon on the 5th.
Then aim at the Messier or M-35 cluster and the moon on the 7th and the Beehive cluster and the moon on the 10th.
Meanwhile, at dusk, catch Saturn as it dips closer to the western horizon and pairs up with Mercury on the 24th through the 28th.
Also, Comet C/2017 O1 should still be a binocular-friendly magnitude 7 or 8 greenish object in November. Use Polaris, the North Star as a guide. Look in the East to Northeast sky in the late evening.
Watch the full What’s Up for November Video:
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From an astronauts perspective, what is your opinion on movies like Interstellar and Gravity?
Will ordinary sunglasses suffice?
Unfortunately not. Sunglasses are not sufficient to ever look directly at the Sun. You can find glasses and filters that are safe here https://eclipse2017.nasa.gov/safety And if you can’t find any that will get to you in time for the eclipse on Monday (you can always use them to look at the Sun at a later time to see sunspots), you can make a pin hole projector! https://eclipse.aas.org/eye-safety/projection I think those are fantastic fun!
Tonight, you can see Venus along with a crescent moon, Mars and Uranus just after sunset. No binoculars needed!
While there are no meteor showers this month, behold the zodiacal light!
This phenomenon is caused when sunlight reflects off dust particles in the plane of our solar system. Use Venus and Mars as a cone-shaped guide on the western horizon in late February and March.
Comet 45P will be visible using binoculars and telescope and will make its closest approach to Earth on February 11.
Finally, bright asteroid Vesta can be found in the constellation Pisces.
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As Neil Armstrong became the first human to step foot onto another world on July 20, 1969, lunar dust collected on the boots of his spacesuit. He peered through the gold coating of his visor and looked out across the surface of the Moon, an entirely different landscape than he was used to.
Now, just in time for the 50th anniversary of the Moon landing, you can experience the boots that stepped in Moon dust and the visor that saw the moonscape up close. Neil Armstrong’s spacesuit from the historic Apollo 11 Moon landing is on display for the first time in 13 years in its new display case in the Wright Brothers & the Invention of the Aerial Age Gallery of the National Air and Space Museum.
This week, you can also watch us salute our Apollo 50th heroes and look forward to our next giant leap for future missions to the Moon and Mars. Tune in to a special two-hour live NASA Television broadcast at 1 p.m. ET on Friday, July 19. Watch the program at www.nasa.gov/live.
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Two galaxies are locked in a deadly embrace in this Hubble Space Telescope image. Once normal, sedate spiral galaxies like the Milky Way, this galactic pair has spent the past few hundred million years sparring. The clash is so violent that stars have been ripped from their host galaxies to form a streaming arc between the two.
The far-flung stars and streamers of gas stretch out into space, creating long tidal tails reminiscent of antennae (not visible in this close-up Hubble view). Clouds of gas blossom out in bright pink and red, surrounding the bright flashes of blue star-forming regions — some of which are partially obscured by dark patches of dust.
Hubble’s observations have uncovered over 1,000 bright, young star clusters bursting to life as a result of the head-on wreck. The sweeping spiral-like patterns, traced by bright blue star clusters, shows the result of a firestorm of star-birth activity, which was triggered by the collision. The rate of star formation is so high that the Antennae galaxies are said to be in a state of starburst, a period in which all of the gas within the galaxies is being used to form stars. This cannot last forever, and neither can the separate galaxies; eventually the nuclei will coalesce and the galaxies will begin their retirement together as one large elliptical galaxy.
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How does the whole sleeping situation work with 0 gravity, or do sleep mid air?
Jupiter climbs higher in the southeast sky earlier in the evening this month, instead of having to wait until midnight for the planet to make an appearance. You can even see with just a pair of binoculars--even the four Galilean moon!
You can even see with just a pair of binoculars--even Io, Europa, Ganymede and Callisto--the four Galilean moons--as they change position each night!
Our moon appears near Jupiter in the nighttime sky from May 5-8.
The moon joins Venus and Mercury in the eastern sky just before sunrise on May 22 and May 23.
Later in the month, our moon pairs up with Mars in the west-northwest sky on May 26.
Saturn will be visible before midnight in early May, rising about 11:30 p.m. and by 9:30 p.m. later in the month. The best time to see Saturn Saturn is when it’s higher in the sky after midnight near the end of the month.
Using a telescope, you may be able to see Saturn’s cloud bands, or even a glimpse of Saturn’s north polar region--views that were beautifully captured by our Cassini spacecraft.
Our Hubble Space Telescope has been exploring the wonders of the universe for nearly 30 years, answering some of our deepest cosmic questions. Some of Hubble’s most exciting observations have been about black holes — places in space where gravity pulls so much that not even light can escape. As if black holes weren’t wild enough already, Hubble has helped us make discoveries that show us they’re even weirder than we thought!
First, these things are all over the place. If you look at any random galaxy in the universe, chances are it has a giant black hole lurking in its heart. And when we say giant, we’re talking as massive as millions or even billions of stars!
Hubble found that the mass of these black holes, hidden away in galactic cores, is linked to the mass of the host galaxy — the bigger the galaxy, the bigger the black hole. Scientists think this may mean that the black holes grew along with their galaxies, eating up some of the stuff nearby.
A globular cluster is a ball of old, very similar stars that are bound together by gravity. They’re fairly common — our galaxy has at least 150 of them — but Hubble has found some black sheep in the herd. Some of these clusters are way more massive than usual, have a wide variety of stars and may even harbor a black hole at the center. This suggests that at least some of the globular clusters in our galaxy may have once been dwarf galaxies that we absorbed.
While black holes themselves are invisible, sometimes they shoot out huge jets of energy as gas and dust fall into them. Since stars form from gas and dust, the jets affect star birth within the galaxy.
Sometimes they get rid of the fuel needed to keep making new stars, but Hubble saw that it can also keep star formation going at a slow and steady rate.
If you’ve ever spent some time stargazing, you know that staring up into a seemingly peaceful sea of stars can be very calming. But the truth is, it’s a hectic place out there in the cosmos! Entire galaxies — these colossal collections of gas, dust, and billions of stars with their planets — can merge together to form one supergalaxy. You might remember that most galaxies have a supermassive black hole at the center, so what happens to them when galaxies collide?
In 2018, Hubble unveiled the best view yet of close pairs of giant black holes in the act of merging together to form mega black holes!
What better way to spice up black holes than by throwing gravitational waves into the mix! Gravitational waves are ripples in space-time that can be created when two massive objects orbit each other.
In 2017, Hubble found a rogue black hole that is flying away from the center of its galaxy at over 1,300 miles per second (about 90 times faster than our Sun is traveling through the Milky Way). What booted the black hole out of the galaxy’s core? Gravitational waves! Scientists think that this is a case where two galaxies are in the late stages of merging together, which means their central black holes are probably merging too in a super chaotic process.
Want to learn about more of the highlights of Hubble’s exploration? Check out this page! https://www.nasa.gov/content/goddard/2017/highlights-of-hubble-s-exploration-of-the-universe
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