How tornadoes are formed

Infographic of a tornado. Credit: infothread.info

A tornado is a meteorological phenomenon which is formed by an air column that it turns around at high speed, it is violent and potentially dangerous. The tornadoes can occurs in any place of Earth, with exception to the polar region. However, in the USA, particularly in a region called Tornado Alley, this kind of nature's force has a higher number of events.

Apparently tornadoes are attached to a strong interaction between the mass flow of air upward and downward and cause an intense movement in the center of clouds of super-charged storm cells. These cells usually formed due to the contrast between two large air masses at different pressures and temperatures.

After touch down, a tornado can reach a range between 100 to 1200 meters, moving a length of approximately 30 km.

Formatio of a tornado. Credit: wikimedia

1 - Prior to the development of the storm, a change in wind direction and speed with an increase in the height tendency to create a horizontal rotation in the lower atmosphere. This change in direction and wind speed is called wind shear.
2 - Air ascending from the lower atmosphere enters the storm and the air rotating inclined from the horizontal position to the vertical position change.
3 - Then there is the formation of a rotation area with a length of 4.6 km, which corresponds to nearly entire length of the storm. Most strong and violent storms are formed in these areas of extensive rotation.
4 - The cloud base and its area of rotation are known as wall cloud. This area is generally no rain.
Reference: wikipedia

As I said before, it is in the US were the number of this event s are higher. Despite a decrease in the number of victims, the number of tornadoes has been increasing over the years.

Number of tornados in USA, between 1918 and 2008. Credit: Chuck Doswell

Air cold from North and Warm from South. Font: Oklahoma Climatological Survey. Adaptation: José Gonçalves

This phenomenon occurs in large numbers in the United States due to large cold air masses coming from the north and warm air masses coming from the Gulf of Mexico. As this aisle there are no major natural barriers such as exists in the West, we have a great area where these masses can collide and form the super storm cells and that will become responsible for the emergence of tornadoes.

However, despite the increased number of tornadoes, the number of tornadoes with great destructive power has decreased compared to previous decades.

Tornadoes can be classified regarding their destructive power. This scale is known by the Fujita scale.

In the table we have the scale and its relationship to wind speed, track width, track length and damage.

The maximum value defined so far is F5, where the wind velocity may reach values ​​between the 420 and the 530 km / h. (260 to 329 mph)

Classification	Velocity of winds (km/h)	Base of the tornado (meters)	Track (km)	Damage
F0	65-115	3-20	0-2	Light
F1	115-180	10-100	1-5	Moderated
F2	180-250	50-500	2-20	Strong
F3	250-330	500-1000	5-60	Severe
F4	330-420	1000-2000	10-150	Devastating
F5	420-530	2000-5000	10-500	Massive destruction

Table: Fujita's scale, correlation with another characteristics of the tornados.

In this graph we have the classification of the tornadoes and the number of events since 1950's.

Number of tornadoes and its classification since 1950's. Credit: Harpers-Ferry Weather

The phenomenon in the United States have been monitored in recent years with some concern. This seems to come from the fact that these phenomena are occurring earlier than normal for its season and a very large number.

In the graph there is the anomalous 2008 and 2011. This year could set a new record for the number of tornadoes that occurred in the United States.

Versão portuguesa aqui.

The Higgs Boson and Our Life

On July 4th, 2012, the ATLAS and CMS experiments operating at the CERN Large Hadron Collider (LHC) announced the discovery of a new particle compatible with the Higgs boson (hunted for almost 50 years), which is a crucial piece for our understanding of fundamental physics and thus the structure and evolution of the universe. This lecture describes the unprecedented instruments and challenges that have allowed such an accomplishment, the meaning and relevance of this discovery to physics, and the implications to our day to day lives. 

Speaker: Dr. Fabiola Gianotti - CERN
Date: April 30, 2013

What happened to antimatter? - Rolf Landua

Me and Rolf Landua holding the antimatter container of DaVinci's Code

Do you remember the antimatter bomb in the DaVinci's Code movie?

In my journey at CERN, Rolf Landua gave a lecture about antimatter. Basically the topics in the lecture was this questions: What is it? Where is it create? How can be created? What is the mystery behind it? How can we study it? Can we use it as a energy font or a bomb? Is any antimatter in our daylife?

In particle physics, antimatter is material composed of antiparticles, which have the same mass as particles of ordinary matter but have opposite charge and quantum spin. Antiparticles bind with each other to form antimatter in the same way that normal particles bind to form normal matter. For example, a positron (the antiparticle of the electron, with symbol e+) and an antiproton (symbol p) can form an antihydrogen atom. Furthermore, mixing matter and antimatter can lead to the annihilation of both, in the same way that mixing antiparticles and particles does, thus giving rise to high-energy photons (gamma rays) or other particle–antiparticle pairs. The end result of antimatter meeting matter is a release of energy proportional to the mass as the mass-energy equivalence equation, E=mc² shows.

At this time, the apparent asymmetry of matter and antimatter in the visible universe is one of the greatest unsolved problems in physics.

Antimatter is created in the LHC, and the LHCb is the detector responsible to detect particles in the antiprotons' collisions. The antiprotons' production is achieved with the collisions between protons and nucleus of Iridium, Cupper, and others. The antiprotons are decelerated and keep trapped with a combination of electric and magnetic fields (so it doesn't touch matter). In this way, the resultant material is detected by the detector before the annihilation. That event is one of the biggest mysteries of the Big Bang, and scientist are trying to answer it: the domination of the matter over the antimatter.

FDG is a glucose molecule, with fluorine-18 attached

This antimatter cannot be used as energy or weapon because we need energy to create it. Imagine that we want to produce 0.5 g of antimatter. Well, we need 22 kton (22,000 ton) of TNT (almost the same value of the Hiroshima's bomb), to produce 0.5 g of matter and antimatter. The energy in this process is about 4.5 x 10¹³ J. The total energy that we need (because the efficiency is 10^-9 %) will be 4,5 x 10²² J. Even with CERN's discount made by French Electric Company [1 kwh = 3,6 x 10⁶ J= 0,1 €], the total cost will be 1 x 10⁸ € and it will be take a billion years to produce and supply this production to CERN.

But, antimatter is used in our body for PET scan detection. The glucose has a fluorine-18 attached that will emit positrons when that molecule travels in our body, and the scanner detects where the positrons go.

The next step that scientist at CERN are trying to develop is to use positrons and antiprotons as therapy in some deceases.

References:

• Antimatter - Wikipedia
• Having a Pet Scan
• Antimatter presentation - Rolf Landua, CERN

TEDxCERN

Credit: CERN

Going beyond particle physics, TEDxCERN will provide a stage for the expression of science in multiple dimensions and disciplines, unveiling a world in which physics intersects with other multi-dimensional disciplines and thought. TEDxCERN will take place on 3 May 2013 at CERN, near Geneva, Switzerland, and will be webcast live throughout many of CERN's member institutes.
Go here to watch: http://tedxcern.web.cern.ch/

NASA | SDO: Three Years of Sun in Three Minutes

Three years of Sun in three minutes

In the three years since it first provided images of the sun in the spring of 2010, NASA's Solar Dynamics Observatory (SDO) has had virtually unbroken coverage of the sun's rise toward solar maximum, the peak of solar activity in its regular 11-year cycle. This video shows those three years of the sun at a pace of two images per day.

SDO's Atmospheric Imaging Assembly (AIA) captures a shot of the sun every 12 seconds in 10 different wavelengths. The images shown here are based on a wavelength of 171 Angstroms, which is in the extreme ultraviolet range and shows solar material at around 600,000 Kelvin. In this wavelength it is easy to see the sun's 25-day rotation as well as how solar activity has increased over three years.

During the course of the video, the sun subtly increases and decreases in apparent size. This is because the distance between the SDO spacecraft and the sun varies over time. The image is, however, remarkably consistent and stable despite the fact that SDO orbits the Earth at 6,876 miles per hour and the Earth orbits the sun at 67,062 miles per hour.

Such stability is crucial for scientists, who use SDO to learn more about our closest star. These images have regularly caught solar flares and coronal mass ejections in the act, types of space weather that can send radiation and solar material toward Earth and interfere with satellites in space. SDO's glimpses into the violent dance on the sun help scientists understand what causes these giant explosions -- with the hopes of some day improving our ability to predict this space weather.

There are several noteworthy events that appear briefly in this video. They include the two partial eclipses of the sun by the moon, two roll maneuvers, the largest flare of this solar cycle, comet Lovejoy, and the transit of Venus. The specific time for each event is listed below, but a sharp-eyed observer may see some while the video is playing.

00:30;24 Partial eclipse by the moon

00:31;16 Roll maneuver

01:11;02 August 9, 2011 X6.9 Flare, currently the largest of this solar cycle

01:28;07 Comet Lovejoy, December 15, 2011

01:42;29 Roll Maneuver

01:51;07 Transit of Venus, June 5, 2012

02:28;13 Partial eclipse by the moon

More information about this video, as well as full HD version of all four wavelengths and print-resolution stills are public domain and can be viewed and downloaded at: http://svs.gsfc.nasa.gov/vis/a010000/...

This video is public domain and can be downloaded.

CREDIT: NASAexplorer channel in Youtube

Max Planck - Born in April 23, 1858

Max Karl Ernst Ludwig Planck, (April 23, 1858 – October 4, 1947) was a German theoretical physicist who originated quantum theory, which won him the Nobel Prize in Physics in 1918.

Max Planck. Credit: Wikipedia

Planck made many contributions to theoretical physics, but his fame rests primarily on his role as originator of the quantum theory. This theory revolutionized human understanding of atomic and subatomic processes, just as Albert Einstein’s theory of relativity revolutionized the understanding of space and time. Together they constitute the fundamental theories of 20th-century physics. Both have led humanity to revise some of its most cherished philosophical beliefs, and have brought about industrial and military applications that affect many aspects of modern life.

His work on Black Body Radiation was the begging of Quantum Mechanics.

The Planck constant (denoted h, also called Planck's constant) is a physical constant that is the quantum of action in quantum mechanics. The Planck constant was first described as the proportionality constant between the energy (E) of a photon and thefrequency (f) of its associated electromagnetic wave. This relation between the energy and frequency is called the Planck relation: E = h f.

"Blackbody radiation" or "cavity radiation" refers to an object or system which absorbs all radiation incident upon it and re-radiates energy which is characteristic of this radiating system only, not dependent upon the type of radiation which is incident upon it. The radiated energy can be considered to be produced by standing wave or resonant modes of the cavity which is radiating. 
From the assumption that the electromagnetic modes in a cavity were quantized in energy with the quantum energy equal to Planck's constant times the frequency, Planck derived a radiation formula. The average energy per "mode" or "quantum" is the energy of the quantum times the probability that it will be occupied:
This average energy times the density of such states, expressed in terms of either frequency or wavelength
gives the energy density , the Planck radiation formula.

Font: HyperPhysics, Wikipedia

Here is a simulation of the Blacbody radiation (PhET)

You can also try this cool simulation from Open Source Physics.

Finally watch this video with a brief History of Quantum Mechanics:

A whole new view of the Horsehead Nebula

In this episode of the Hubblecast celebrates 23 years of the NASA/ESA Hubble Space Telescope, by unveiling a beautiful and striking new image of the Horsehead nebula. 

Dr Joe Liske (aka Dr J) explains the secrets of nebulae, cosmic clouds of gas and dust that have been the subjects of some of Hubble's most striking astronomical images. The Horsehead nebula is one of the most distinctive, and is now shown in a whole new light thanks to a stunning new infrared image — revealing the delicate wisps of gas that are normally hidden by the thick dust that makes up the Horsehead's famous and familiar shape.

More information and download-options:

http://www.spacetelescope.org/videos/...

Credit: ESA/Hubble

How does an atom-smashing particle accelerator work? - Don Lincoln