Thursday, August 24, 2006

Pluto loses status as a planet

8 Classic Planets + 3 Dwarf Planets
Astronomers meeting in the Czech capital have voted to strip Pluto of its status as a planet. About 2,500 experts were in Prague for the International Astronomical Union's (IAU) general assembly.

The scientists rejected a proposal that would have retained Pluto as a planet and brought three other objects into the cosmic club. Pluto has been considered a planet since its discovery in 1930 by the American Clyde Tombaugh.


The ninth planet will now effectively be airbrushed out of school and university textbooks.

read more in BBC

Wednesday, August 23, 2006

Astronomers lean towards eight planets

Finally, astronomers could be homing in on a definition of the word planet. After a day of public bickering in Prague, followed by negotiations behind closed doors, the latest draft resolution was greeted with a broadly friendly reception.
If accepted on Thursday, it would be bad news for Pluto, which would no longer be a full-fledged planet.
read more in New Scientist

Tuesday, August 22, 2006

Found Dark Matter

Dark Matter which makes up 25% of the Universe finally detected. Dark matter eluded scientists for years as it doesn’t emit or reflect light. Scientists found proof of dark matter in the galaxy cluster 1E0657-556. The evidence provided by a cosmic collision between two huge clusters of galaxies. As per Maxim Markevitch of the Harvard Smithsonian Center in Cambridge, Massachusetts, it is the “most energetic cosmic show, besides the Big Bang” that we are aware of.

Image to right: A purple haze shows dark matter flanking the "Bullet Cluster." Image Credit: X-ray: NASA/CXC/M.Markevitch et al. Optical: NASA/STScI; Magellan/U.Arizona/D.Clowe et al. Lensing Map: NASA/STScI; ESO WFI; Magellan/U.Arizona/D.Clowe et al.

The known universe (to us) is composed of 5% of matter (which includes, Free Hydrogen & Helium, Stars, Heavy elements (Earth), Ghostly neutrinos, air, life etc) while the rest 95% is made up of Dark Matter and Dark Energy. The matter in the known universe is made up of Quarks (Up and Down) and Electrons. Proton consists of 2 Up Quarks and 1 Down Quark while Neutron consists of 2 Down Quark and 1 Up Quark. This is the first family of fermions in the standard model.

The scientists discovered the gravitational signature of the dark matter. This signature is the by product of an immense collision of two huge galaxies (happened 100 million years ago) tearing apart the normal matter and the dark matter. The kinetic energy of this collision is good enough destroy planet Earth ten trillion trillion times. The dark matter is not seen, however, its gravity has a predictable effect on the observations. The blue color in the image shows gravity fields observed by how light from each background galaxy is distorted.

As per Robert Roy Britt of Space.Com here’s what the image reveals:

“The hot gas – normal matter – was slowed by a drag force described as the cosmic equivalent of air resistance. But the dark matter was not slowed by this effect, presumably because it does not interact with normal matter, as theory had predicted. So the normal matter and dark matter became separated.”

References

1. AstroPhysics - A direct empirical proof of the existence of Dark Matter
2. BBC – Team finds ‘proof’ of dark matter
3. CNN –
Scientists: Dark Matter exists!
4. Space.Com –
Colossal cosmic collision reveals dark matter
5. NASA – A Matter of fact
6. BBC –
Dark Matter comes out of cold
7. Wikipedia.org –
Dark Matter
8. Wikipedia.org –
Dark Energy
9. Scientific American -
Colliding Clusters shed light on Dark Matter
10. Scientific American - Supernovae Back Einstein's Blunder

Saturday, August 19, 2006

Astronomers sharply divided on new planet definition

By Robert Roy Britt, SPACE.com

A 12-person committee representing the world's largest group of planetary scientists on Thursday threw its support behind a new planet-defintion proposal that would increase the tally of planets in our solar system to 12. More dissent emerged, too, from several prominent planet experts.

The definition, proposed yesterday at a meeting of the International Astronomical Union (IAU) in Prague, preserves Pluto's planet status and essentially classifies as planets all round objects that orbit the Sun and do not orbit another planet. The tally of planets is expected to eventually soar into the hundreds if the resolution is passed by a vote next week.

The Division for Planetary Sciences (DPS), a group within the American Astronomical Society, has the opposite view. The 12-member DPS Committee, elected by the membership, "strongly supports the IAU resolution," according to a statement released Thursday.

read more .... usatoday.com

Earth's moon could become a planet
By Robert Roy Britt SPACE.com
Friday, August 18, 2006; Posted: 12:11 p.m. EDT (16:11 GMT)

(SPACE.com) -- If astronomers approve a newly proposed planet definition next week, things could get really strange. Sure, asteroid Ceres will become a planet. Pluto's moon Charon will become a planet. But we're talking really strange.

Eventually, if Earth and its moon survive long enough, the moon will have to be reclassified as a planet, said Gregory Laughlin, an extrasolar planet researcher at the University of California, Santa Cruz.

The new definition, proposed this week by the International Astronomical Union (IAU), basically says every round object orbiting the sun is a planet, unless it orbits another planet. But there is a big caveat: If the center of gravity, called the barycenter, is outside the larger object, then the smaller object is a planet. That wording elevates Pluto's moon Charon to planethood, an idea some astronomers have criticized

read more in .... cnn.com


Pluto may yet lose planet status

Stephen Battersby - 20:24 18 August 2006 - NewScientist.com news service

We were about to gain a horde of new planets; now we might lose one instead.
In Prague, astronomers are trying to define what it means to be a planet. A draft definition released on Wednesday would have extended the the club from the conventional nine to twelve, and soon to many more (see
Three new planets may join solar system).


read more in .....
New Scientist

Wednesday, August 16, 2006

Solar System with 12 Planets

IAU’s executive committee submitted (which only submits recommendations likely to get two thirds approval from the group of 2500 astronomers from 75 nations meeting in Prague to decide a universal definition of a planet) a draft proposal to expand the Solar System to 12 planets. They will have two brain storming sessions before they vote on the resolution next week (August 21-25, 2006).

The change will force the schools across the world to change their text books and the elementary school solar system models. More interestingly astrologers need to tweak their formulas to make predictions as their model of classic nine planets is not valid anymore! :-)

The proposed new definition of a planet is as follows

- Any round object larger than 500 miles (800 Km) in diameter
- It must orbit the sun
- A mass roughly one-12,000th that of Earth.

Pluto and its moon Charon will be first double planet while Ceres is only 592 miles (952 Km) in diameter compared to 2003 UB313 which is 1490 miles (2400 km) in diameter.

Following will be the 12 planets if the resolution is approved (diameter in brackets)

1. Mercury (3031 miles)
2. Venus (7520 m)
3. Earth (7926 m)
4. Mars (4194 m)
5. Ceres (592 m)
6. Jupiter (88,736 m)
7. Saturn (74,978 m)
8. Uranus (32,193 m)
9. Neptune (30,775 m)
10. Pluto (1430 m)
11. Charon (750 m)
12. 2003 UB313 or Xena (1490 m)

Images

In this artist's impression the planets are drawn to scale, but without correct relative distances.
Credit: The International Astronomical Union/Martin Kornmesser

Resources

1. IAU.org –
Draft Definition of planet and plutons
2. BBC – Planets plan boosts tally to 12
3. BBC – Proposed new planets (video)
4. New York Times – For now, Pluto holds its place in our Solar System
4. CNN – Proposal would increase planets from 9 to 12
5. Scientific American – New Planet Definitions Enlarges Solar System
6. Telegraph UK - Never mind the dwarfs, just be happy for pluto