Is Pluto a planet? The votes are IN !!

Dear readers and followers,

What is a planet? For generations of kids the answer was easy. A big ball of rock or gas that orbited our Sun, and there were nine of them in our solar system. But then astronomers started finding more Pluto-sized objects orbiting beyond Neptune. Then they found Jupiter-sized objects circling distant stars, first by the handful and then by the hundreds. Suddenly the answer wasn’t so easy. Were all these newfound things planets?

Since the International Astronomical Union (IAU) is in charge of naming these newly discovered worlds, they tackled the question at their 2006 meeting. They tried to come up with a definition of a planet that everyone could agree on. But the astronomers couldn’t agree. In the end, they voted and picked a definition that they thought would work.

The current, official definition says that a planet is a celestial body that: "is in orbit around the Sun, is round or nearly round, and has “cleared the neighborhood” around its orbit."

But this definition baffled the public and classrooms around the country. For one thing, it only applied to planets in our solar system. What about all those exoplanets orbiting other stars? Are they planets? And Pluto was booted from the planet club and called a dwarf planet. Is a dwarf planet a small planet? Not according to the IAU. Even though a dwarf fruit tree is still a small fruit tree, and a dwarf hamster is still a small hamster.

Eight years later, the Harvard-Smithsonian Center for Astrophysics decided to revisit the question of “what is a planet?” On September 18th, a debate has been organized and its goal: to find a definition that the eager public audience could agree on!

Science historian Dr. Owen Gingerich, who chaired the IAU planet definition committee, presented the historical viewpoint. Dr. Gareth Williams, associate director of the Minor Planet Center, presented the IAU’s viewpoint. And Dr. Dimitar Sasselov, director of the Harvard Origins of Life Initiative, presented the exoplanet scientist’s viewpoint.

Zingerich argued that “a planet is a culturally defined word that changes over time,” and that Pluto is a planet. Williams defended the IAU definition, which declares that Pluto is not a planet. And Sasselov defined a planet as “the smallest spherical lump of matter that formed around stars or stellar remnants,” which means Pluto is a planet.

After these experts made their best case, the audience got to vote on what a planet is or isn’t and whether Pluto is in or out. The results are in, with no hanging chads in sight.

According to the audience, Sasselov’s definition won the day, and Pluto IS a planet.

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NASA observed an asteroid collision creating a huge cloud: rocky planet creation ?

Dear readers and followers,

The NASA's telescope, called Spitzer Space Telescope (SST) has spotted an eruption of dust around a young star, possibly the result of a smashup between large asteroids. This type of collision can eventually lead to the formation of planets.

Credit image: +NASA Jet Propulsion Laboratory 

Scientists had been regularly tracking the star, called NGC 2547-ID8, when it surged with a huge amount of fresh dust between August 2012 and January 2013. While dusty aftermaths of suspected asteroid collisions have been observed by Spitzer before, this is the first time scientists have collected data before and after a planetary system smashup. The viewing offers a glimpse into the violent process of making rocky planets like ours.

Credit image: +NASA Jet Propulsion Laboratory / +The University of Arizona 

Rocky planets begin life as dusty material circling around young stars. The material clumps together to form asteroids that ram into each other. Although the asteroids often are destroyed, some grow over time and transform into proto-planets. After about 100 million years, the objects mature into full-grown, terrestrial planets. Our moon is thought to have formed from a giant impact between proto-Earth and a Mars-size object.

In the new study, Spitzer set its heat-seeking infrared eyes on the dusty star NGC 2547-ID8, which is about 35 million years old and lies 1,200 light-years away in the Vela constellation. Previous observations had already recorded variations in the amount of dust around the star, hinting at possible ongoing asteroid collisions. In hope of witnessing an even larger impact, which is a key step in the birth of a terrestrial planet, the astronomers turned to Spitzer to observe the star regularly. Beginning in May 2012, the telescope began watching the star, sometimes daily. A dramatic change in the star came during a time when Spitzer had to point away from NGC 2547-ID8 because our sun was in the way. When Spitzer started observing the star again five months later, the team was shocked by the data they received: a very thick cloud of dusty debris now orbits the star in the zone where rocky planets form. As the scientists observe the star system, the infrared signal from this cloud varies based on what is visible from Earth. For example, when the elongated cloud is facing us, more of its surface area is exposed and the signal is greater. When the head or the tail of the cloud is in view, less infrared light is observed. By studying the infrared oscillations, the team is gathering first-of-its-kind data on the detailed process and outcome of collisions that create rocky planets like Earth.

The team is continuing to keep an eye on the star with Spitzer. They will see how long the elevated dust levels persist, which will help them calculate how often such events happen around this and other stars, and they might see another smashup while Spitzer looks on.

Source: NASA

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Explore the night sky with Google Glass

Dear readers and followers,

If you are on of the lucky Google Glass explorer, you can explore the night sky thanks to the connected glasses developed and sold by the firm of Mountain View.

The app, called Star Chart has been specifically developed for Google Glass making many changes both big and small to the UI, interface and feature-set. With Star Chart for Google Glass you will get to explore the wonders of our universe by simply looking up at the sky to discover the stars, planets and constellations above you.
Features of Star Chart for Google Glass include:

• All the visible stars of the northern and southern hemispheres.

• All the planets of the solar system, the Moon, the Sun and Pluto.

• All 88 constellations, with imagery based on the beautiful artwork of 17th century astronomer Johannes Hevelius.

• Audio descriptions of all the planets and many of the brightest stars.

To launch Star Chart for Google Glass simply say: "OK Glass" followed by "Explore the stars".
Once Star Chart has launched simply look at the area of the night sky you are interested and Star Chart will show you what you are looking at.

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Venus, Mercury and Saturn in 2005 in Chile

Credits: Stephane Guisard

Far away solar system with two Earth-like planets

Scientific looking the Universe have found a new solar system around Kepler-62. and there is at least five planets which orbit around the star. But the great news is that and two of them are Earth-sized and orbit the star in its habitable zone.

The two planets, called Kepler-62e and Kepler-62f, are both bigger than Earth, but not by much; they are 1.6 and 1.4 times the Earth’s diameter, respectively. Kepler-62e orbits the star every 122 days, while Kepler-62f, farther out, takes about 267 days.

Given the temperature and size of the parent star, this means that both planets are inside the zone around the star where water on the surface could be a liquid. 

One of the reasons the scientific look out into the Universe is to learn more about ourselves. Certainly, finding planets that are different than ours provides us with context, a there-but-for-the-grace-of-God-go-we sort of perspective.