Asteroids •

Martian Moons History

July 6, 2016 By Rebecca McGhee Leave a Comment

The two small and irregular Martian moons may have been the leftovers of a massive collision.

A new study published in the Nature Geoscience journal rewrites the history of Martian moons. The two satellites that can be seen now orbiting the planet are only the remains of the satellite fleet that Mars once seemed to have.

Until now, scientists believed that the two Martian moons were asteroids that got drawn into the planet’s gravitational field. However, the regular and constant orbit of the two moons could not be explained by this theory, as asteroids do not prove to be such obedient satellites.

The new research suggests that the space rocks and many others were created by a massive impact between an asteroid and Mars. The destruction of the asteroid threw over into space a lot more satellites than we can now see next to the planet.

At the present moment, the Red Planet has only two moons, Phobos, and Deimos.

For some time now, scientists tried to prove that the two moons have been created by an impact. The theory is contradicted by other astronomers that say that the satellites are too small to have been set up by an impact. Phobos is 14 miles wide, and Deimos has 8 miles in length.

The Belgian researchers introduced a new variable in the model. A third larger moon could have co-existed with the two small satellites. All of them might have resulted from the same impact.

The fate of the third moon was to disappear into space.

The Borealis basin on Mars was long suspected by scientists to have been produced by a massive collision. The crater covers two-fifths of the surface. Researchers estimated that the object that might have created the basin had a length of 1,250 miles.

However, a collision with an object that big would have thrown into space hundreds of rocks with the dimension of Phobos and Deimos. As to explain the difference in mass, the scientists came up with the idea of a larger moon and other rocks that may have been projected into space after the impact.

Out of the materials created by the explosion, only Phobos and Deimos remained close to the planet. The rest of them went on into a space journey of their own, as the gravitational field on Mars was not strong enough to induce them a steady orbit.

But for a certain period of time in the history of Mars, the planet might have been surrounded by a disk of space debris and rock materials that remained after the collision. The materials thrown into the orbit would have included a 125 miles moon.

The gravitational force of Mars and the one of the larger moon were powerful enough to keep small rocks close together. In time, the ring of space debris dissipated into space, and only Phobos and Deimos remained to orbit the planet.

As new and exciting the new model may be, scientists now face a greater problem – finding the large ex-satellite of Mars.

Image Source: Wikipedia

What Really Happens To The Missing Asteroids Up There

February 19, 2016 By Brian Galloway Leave a Comment

Asteroids are spectacularly destroyed before reaching the Sun.

New study reveals what really happens to the missing asteroids up there, in our Solar System. An international team of scientists have debunked the theory that asteroids and comets end their existence with a final plunge into the sun. It turns out, they disintegrate long before that.

Asteroids are nothing but small, airless rocky worlds revolving around the sun, that are too small to be called planets. They are also known as planetoids or minor planets. In total, the mass of all the asteroids is less than that of Earth’s moon. But despite their size, asteroids can be dangerous. Many have hit Earth in the past, and more will crash into our planet in the future.

That’s one reason scientists study asteroids and are eager to learn more about their numbers, orbits and physical characteristics. This is how they came up with this new finding regarding the death of these ‘minor planets’. The study may bring us closer to understanding how to protect the Earth from an asteroid strike.

Until recently, scientists believed that the demise of asteroids close to Earth happen in a fiery collision with the sun. But by examining nearly 9,000 near-Earth objects, or NEOs, an international team of researchers have recently found that asteroids and comets crumble long before they reach the surface of the blazing star.

So, it turns out that the asteroids are actually dying a slow death, not unlike humans in their later stages of life, they are simply breaking down.

The team’s work also helps explain several discrepancies between observations and predictions of the distribution of small objects in our Solar System. Meteors are such an object. These are effectively tiny bits of dust and rock dislodged from the surfaces of asteroids and comets that then end their lives burning up as they enter our atmosphere.

Observations and studies have established that meteors often travel in ‘streams’ that follow the path of their parent object. However, in almost all cases astronomers have been unable to match most of the meteor streams on orbits closely approaching the Sun with known parent objects.

What the latest study suggests is that the parent objects were completely destroyed when they came too close to the Sun, leaving behind streams of meteors but no parent NEOs. They also found that darker asteroids are destroyed farther from the Sun than brighter ones.

This case is explained by an earlier discovery that NEOs that approach closer to the Sun are brighter than those that keep their distance from the Sun. The fact that dark objects are more easily destroyed implies that dark and bright asteroids have a different internal composition and structure.

So, brighter asteroids, survive longer than dark asteroids, which absorb more light. And smaller asteroids disintegrate faster than bigger ones.

According to Mikael Granvik, a research scientist at the University of Helsinki and lead author of the study, their new finding allows planetary scientists to understand a variety of recent observations from a new perspective. It also leads to a more profound advance in asteroid science.

Perhaps the most intriguing outcome of this study is that it is now possible to test models of asteroid interiors simply by keeping track of their orbits and sizes.

Granvik stated.

However, the strange case of the missing asteroids is now solved. Perhaps our world would be far different today if it weren’t for the Sun destroying vast numbers of these space-borne objects.

Image Source: wallpaper4me.com.

Watch Out, Planet Earth – An Asteroid Is About To Pass Close By

February 4, 2016 By Rebecca McGhee Leave a Comment

‘Oh… I just wanted to say hello. I’m not staying.’

’Watch out, planet Earth – an asteroid is about to pass close by’ – this is how the experts’ warning would sound like. According to NASA, there is this small asteroid is expected to fly past the Earth during the first week of March.

The asteroid (as long as a basketball court) is called asteroid 2013 TX68. Two years ago, it flew past Earth at a comfortable distance of about 1.3 million miles (2 million kilometers) and who now will fly by our planet again in a few weeks. The difference between the last time and this time is that this time it may be much closer.

So close and yet so far.

The predicted range of distance at which the asteroid will go by is very wide, due to the short tracking time of it, which provided limited information for making future tracking predictions.

It could come as close as 11,000 miles (17,700 kilometers) — less than 5 percent of the distance from Earth to the moon — or stay up to 9 million miles (14.5 million km) away during the flyby.

NASA officials said.

On the other hand, scientists that are interested in the case, hope that the asteroid will be close enough to track more thoroughly during its next flyby, for the purposes of adding extra data to the study and to predict the asteroid’s future path.

Graphic indicating the possible locations asteroid 2013 will be in at the time of its closest approach to Earth on March 5.

Experts believe that if an object as big as asteroid 2013 TX68 were to penetrate the Earth’s atmosphere, it would generate an air burst that is twice as powerful as the one produced during the meteor crash in Chelyabinsk.

Despite the expected close flyby of 2013 TX68 on March 5, there is no danger that the asteroid will collide with Earth on this pass, researchers said. However, there is an extremely slight chance — less than 1 in 250 million — of an impact on Sept. 28, 2017, and even lower odds during flybys in 2046 and 2097.

The possibilities of collision on any of the three future flyby dates are far too small to be of any real concern.

CNEOS manager Paul Chodas declared. He also added that he fully expects any future observations to reduce this probability even more.

As a conclusion, it is not as bad as it looks. But as you lay down in bed on March 5, think of the rocky body that is about to fly past the Earth – it should suddenly make you feel small.

Image Source: yournewswire.com; www.space.com.

NASA Established a Planetary Defense Program

January 13, 2016 By Chen Lai Leave a Comment

NASA and ESA managed to piece together a full-fledged planetary defense program aimed at protecting Earth from hazardous NEOs.

With all the space junk floating around Earth, it’s no wonder that people are beginning to thinks that apocalyptic scenarios like the one depicted in Armageddon can become reality. For this reason, NASA established a planetary defense program, a collaboration between several space agencies aimed at protecting the Earth from space threats.

This doesn’t necessarily mean that we are going to get hit by a big hunk of space debris, but it is very important to exercise caution in this matter. And as more NEO’s (Near Earth Objects) are being detected each day, NASA’s initiative couldn’t have come at a better time.

And so NASA officially announced its brand new space defense program called the Planetary Defense Coordination Office or PDCO for short.

PDCO’s mandate will be to identify NEO’s, assess the potential threat of the object, and, if necessary, to take any measures to prevent the object from colliding with our planet. I don’t think that we’ll be getting a Harry Stamper to drill the brains out of an asteroid, but we can sure that the boys and girls from NASA have some decent pieces of equipment standing by to offer protection from this kind of threat.

NASA established a planetary defense program in the hope that doomsday scenarios will never take place. As said, the Office has a dual mandate: to identify and catalog potential hazardous near-Earth object and, if it necessary, to coordinate a with other space agencies in order to protect Earth.

On the subject of protection against potentially hazardous NEOs, NASA has cooked up quite a plan. With the office in the state, the North American space agency was partnered up with the European Space Agency to refine the defense plan.

Moreover, it would seem that the ESA has worked, for some time now, on certain projects in involving planetary defense.

The Planetary Defense Coordination Office is run by NASA’s Science Directorate. As we mentioned, the program must be capable of detecting near-Earth objects large enough to pose a threat to our planet.

A space object can be regarded as a threat towards out planet if it has more than 30 to 50 meters in diameter. Also, the office would declare a critical condition if such an object gets within a range of 150 million kilometers.

The most common methods employed to identify hazardous space objects are NASA’s ground telescopes and the novel near-Earth object wise infrared telescope, which is NASA’s newest asset.

NASA established a planetary defense program in order to react in case an asteroid decides to pay us a visit.

Photo credits:www.wikipedia.org

Study Reveals, Long-Ago Moon’s Magnetic Field Might Have Trumped Earths’

December 6, 2014 By Rebecca McGhee 2 Comments

According to the researchers, the moon once had a magnetic heart, which helped the moon produce a magnetic field stronger than Earth’s now have.

Though, numerous riddles linger about the magnetic field of the moon, for example, what fueled it and when it’s finished, the researchers added.

The moon today does not have an inclusive magnetic field. Nonetheless, asteroids that space explorers gathered amid the Apollo missions proposed the moon once had a magnetic field billions of years back.

However, researchers were unsure whether the moon created a magnetic field the same way Earth does, or if the magnetic fields seen on the moon were rather generated by external powers. For example, celestial effects on the moon could have flickered super-heated plasma that produced solid, concise magnetic fields, clarifying the charged rocks the space travelers found.

In the previous six years or thereabouts, nonetheless, a new era of scientific methods and computer imitations has now presented a solid evidence that the moon may have had a magnetic center like Earth’s.

Magnetic fields are generated by electric currents.

“We believe planets produce magnetic fields by moving electrically directing liquids inside them,” said study co-creator Benjamin Weiss, a planetary researcher at MIT. Streaming metal in the Earth’s center makes the heart of the planet a dynamo — a generator of electrical current — and this dynamo creates the Earth’s magnetic field.

If the moon had a dynamo that produced a magnetic field, that could yield key impending into its concealed internal structure.

Weiss told Space.com, “The crucial inquiry of lunar science for more than four decades, even before the Apollo missions, is to what degree is the moon an unmelted primordial body like numerous space rocks, instead of a dissolved developed body with a multilayered structure, which can have a metallic center with a magnetic field.”

“The moon is halfway between a planet and a little body like a space rock, so building, whether the moon had a primordial dynamo could help demonstrate that it was a very advanced body separated into layers like Earth,” he added. “This would let you know about the derivation of the moon — a few models say the moon began off frosty and unmelted, while others propose it was made from a monster affect and foresee it ought to have been scorched.”

As per the recent scans of magnetized lunar rocks that demonstrate no proof of impacts from celestial effects now give solid confirmation that the moon had a magnetic field 4.25 billion to 3.56 billion years back, no less than 1 billion years after the moon created.

Weiss said, “Earth’s magnetic field is presently 50 microteslas in potency. The early moon may have had a magnetic field that was greater, perhaps up to more than 70 microteslas.”

It stays questionable what may have fueled this shockingly exceptional lunar magnetic field. “It’s difficult to see how the moon’s magnetic field could be as tough as it appeared given how the moon has a little center,” Weiss said. “The moon’s center is perhaps 1/5 to 1/7 the radius of the moon, while the Earth’s center is possibly one-half the planetary range. This implies the surface of the moon is much far from its center than you see with Earth. Since magnetic fields fall quickly in force with distance, it’s tricky to see how the moon could have had a magnetic field that was that that tough throughout its surface.”

All known dynamos of planets are for the most part thought to be fueled by convection, the whipping of liquids because of heat. Given the extent of the moon — just around a quarter of Earth’s distance — the moon ought to have cooled hastily. So a lunar dynamo fueled just by convection ought to have endured just for a couple of hundred million years at most, until around 4.1 billion years ago.

Though, novel models propose that the moon’s innards may have been less gooey than suspected, and that radioactive material inside the moon could have kept it hotter. These elements may have empowered a convection-fueled lunar dynamo to last until maybe 3.5 billion or 3.4 billion years ago.

There are a lot more extraordinary systems that researchers have proposed could have fueled the lunar dynamo.

“One includes smacking the moon sideways with vast effects from space rocks, perhaps a bundle of times,” Weiss said. “You could also use the fact that the moon’s spin wobbles over time, known as precession, and in the past, it wobbled more intensely when it was closer to Earth, and that could likewise inspire movement to power a dynamo. Both these instruments are not known in any planetary body today, and would speak to better approaches for producing magnetic fields.”

MIT Space Scientist not too keen on NASA’s Asteroid in a Bag plan

October 31, 2014 By Brian Galloway 3 Comments

MIT planetary scientist Richard Binzel does not like NASA’s notion of getting an Asteroid in a very large ship and then hurling it into lunar orbit so that astronauts can easily go and explore it.

At a talk last summer he called the Asteroid Return Mission (ARM) as “the emperor with no clothes, or at best with very thin cloth.” In the latest issue of Nature he’s drafted his objections in much severity and also proposed an alternative that he thinks would do justice to the ultimate goal of the Space Age, that is sending astronauts to Mars. His notion is quite simple that why fuss in bringing such an unaccounted asteroid of the solar system to us rather send astronauts to visit them which could also help in the first manned flight to Mars.

In his complete fairness he believes that NASA doesn’t really what to do with its hardware which is a bad thing. When the Obama administration opted out of sending astronauts to the moon again, NASA knew that their new target had to be to push for a visit to an asteroid so they were pretty serious about it until they realized they couldn’t really pull it off especially due to their budget constraints, so they came up with ARM which the most of the space community shunned.

Asteroids are quite common visitors to Earth and even more so fly by close to us. And they are quite interesting things as well; an asteroid a few miles across can cause the sort of planet wide catastrophe that played a big part in ending the dinosaur’s dominance of the Earth. And even a smallish one, like the 60-foot rock that fell near Chelyabinsk, Russia last year can do plenty of damage.

Binzel estimates that there are 10 million of Near Earth Asteroids and at least one passes by as close as the moon every week.

When hanging out with the asteroid, astronauts can do tons of exploration. They could bring samples for study and even look for minerals and so much so they can also test for deflection technologies that could someday come in handy as we saw in the movie “Armageddon”. And this would all come at a fraction of the cost then hurling an asteroid.

Categories