Group items tagged

"We hope to witness two atmospheres colliding," explains David Brain of the University of Colorado's Laboratory for Atmospheric and Space Physics (LASP).  "This is a once in a lifetime event!"

Everyone knows that planets have atmospheres.  Lesser known is that comets do, too.  The atmosphere of a comet, called its "coma," is made of gas and dust that spew out of the sun-warmed nucleus.  The atmosphere of a typical comet is wider than Jupiter.

The timing could scarcely be better.  Just last year, NASA launched a spacecraft named MAVEN to study the upper atmosphere of Mars, and it will be arriving in Sept. 2014 barely a month before the comet. MAVEN is on a mission to solve a longstanding mystery: What happened to the atmosphere of Mars?  Billions of years ago, Mars had a substantial atmosphere that blanketed the planet, keeping Mars warm and sustaining liquid water on its surface. Today, only a wispy shroud of CO2 remains, and the planet below is colder and dryer than any desert on Earth. Theories for this planetary catastrophe center on erosion of the atmosphere by solar wind.

The way we currently reach other worlds with our present technology — or any remote location in the Universe — involves three distinct stages:The initial launch, which overcomes the Earth’s gravitational binding energy and starts our spacecraft off with a reasonably large (on the order of a few km/s) velocity relative to the Earth’s motion around the Sun.On-board course corrections, where very small amounts of thrust accelerate the spacecraft to its optimal trajectory.And gravity assists, where we use the gravitational properties of other planets in orbit around the Sun to change our spacecraft’s velocity, either increasing or decreasing its speed with every encounter.It’s through the combination of these three actions that we can reach any location — if we’re patient and we plan properly — with only our current rocket technology.

The initial launch is a very hard part right now. It takes a tremendous amount of resources to overcome the Earth’s gravitational pull, to accelerate a significant amount of mass to the Earth’s escape velocity, and to raise it all the way up through the Earth’s atmosphere.

The researchers suspect they've reached a region of the solar-interstellar boundary that nobody had predicted. In this area, the magnetic field lines of the Sun link up with those of the interstellar field. Scientists are calling this linkage a "highway" for particles to travel along. It lets solar wind particles escape more readily, causing the drop in their intensity. And it opens the door for low-energy cosmic rays to slip in to our Solar System, which is why Voyager 1 is seeing so many of them. According the researchers at the press conference that announced these results, most steady-state models of the Solar System failed to predict anything like this. A few models did have a feature like this, but it was only a transient one that appeared at certain times of the solar cycle.

BANGALORE: India's Mars Orbiter Mission (MOM) will look to have a date with the Siding Spring comet, which will pass very close to the Red Planet on October 19, Isro chairman K Radhakrishnan said on Thursday.

Asked how Nasa could do reprogramming on its MAVEN spacecraft to study the comet, Radhakrishnan said: "MAVEN reached there before us and has completed the orbit around the Red Planet. I have received mails about what they are going to do, and we know what we should. But MOM has to ascertain its position. It will be known in 2-3 days."

The European Space Agency's satellite array dubbed “Swarm” revealed that Earth's magnetic field is weakening 10 times faster than previously thought, decreasing in strength about 5 percent a decade rather than 5 percent a century. A weakening magnetic field may indicate an impending reversal, which scientists predict could begin in less than 2,000 years. Magnetic north itself appears to be moving toward Siberia.

There is a good chance the weakening magnetic field that the Swarm satellites observed will not lead to a full flip. Indeed, Glatzmaier notes that there have been several false starts over geologic history. The intensity of Earth's magnetic field, though waning, now equals its average strength over millions of years. The field would need to weaken at its current rate for around 2,000 years before the reversal process actually begins.

It is hard to know how a geomagnetic reversal would impact our modern-day civilization, but it is unlikely to spell disaster. Although the field provides essential protection from the sun's powerful radiation, fossil records reveal no mass extinctions or increased radiation damage during past reversals. A flip could possibly interfere with power grids and communications systems—external magnetic field disturbances have burned out transformers and caused blackouts in the past. But Glatzmaier is not worried. “A thousand years from now we probably won't have power lines,” he says. “We'll have advanced so much that we'll almost certainly have the technology to cope with a magnetic-field reversal.”

This new theory suggests that all of these infinite multiple worlds overlap and occupy the same region of time and space simultaneously, just like a quantum state. 

Under this new interpretation, some worlds in parallel universes would be nearly identical. In others, the “Butterfly Effect” is responsible for completely different outcomes. Each universe is equally real; it isn’t that one universe is the truth while others are bizarre copies or lesser in any way. Wiseman also believes that the quantum forces responsible for driving this shared existence are also responsible for causing quantum interactions between the worlds.