Albert Einstein (1879-1955) in 1921. Official photograph after receiving his Nobel Prize in Physics that year.

“I believe in intuition and inspiration. Imagination is more important than knowledge. For knowledge is limited, whereas imagination embraces the entire world, stimulating progress, giving birth to evolution. It is, strictly speaking, a real factor in scientific research.” (Albert Einstein)

Albert Einstein was born in Germany, was a physicist, an active pacifist and a violinist. It is among the most charismatic figures of science and his influence in the modern world far transcends the limits of scientific knowledge.

Galaxy IC 3418, and its tail of gas, visible only under ultraviolet light. The gas escapes from some galaxies due to their movement and to interaction with nearby galaxies (http://www.galex.caltech.edu/media/glx2010-02f_img01.html).

The title of this post in portuguese is a funny allitaration, that I bet no one can repeat more than ten times without produce a knot on the tongue (Estrelas Extremófilas Estremecem Estruturas do Estudo de Evolução Estelar).

Astronomers at GALEX project (Galaxy Evolution Explorer) found stars forming in regions of low gas concentration, where we thought there could never be star formation

Our knowledge of stellar evolution seems very good. We easily identify regions of intense star formation and starbursts. We Observe star formation in the disks of spiral galaxies, where we also found a large quantity of gas and dust, ingredients needed to produce stars. Outside the disk, in the halo, we find old stars, which indicates that there we don’t have star formation. Elliptical galaxies are gas-poor and have old stars, which indicates that these galaxies have produced stars with its original gas, and stars are no longer produced at current time.

However …

The GALEX is a space telescope that sees in the ultraviolet range, and is specially sensitive to a kind ultraviolet rays closely related to stars in the early stages of its formation. The telescope observed young stars in places where we didn’t expect to find star formation, like gas lost by galaxies and not enough massive nebulae. A star forming in gas that was taken from a galaxy, is not only a star forming in a region of very low gas concentration, but is also a star forming out of a galaxy!

There is a parameter, called Jeans Mass, which we use to verify whether the internal pressure of a region of gas is sufficient to prevent gravitational collapse or not. If the Jeans Mass indicates that the collapse is possible, this region can be a star-forming region. Perhaps these new observations of stars extremophiles lead us to revise the terms in which we calculate the Jeans Mass.

The term “extremophiles” that is being used to refer to these stars, was borrowed from biology, which uses it to refer to organisms found in regions where life would not be possible for most other organisms, such as in regions submarine under high pressure, or very acidic environments with pH about 2.0 or even more acid.

I think that even a strange extremophile can not read the title of this post in Portuguese ten times without have its tongue tied …

To read more: http://science.nasa.gov/science-news/science-at-nasa/2011/07nov_stellarextremophiles/

Picture by Oliver Staiger, in the region of Swiss Alps, in october 21, 2011 (http://spaceweather.com/submissions/large_image_popup.php?image_name=Olivier-Staiger-IMG_2121_tonemappeds_1319267748.jpg)

We’ll have in the next few nights the meteor shower known as Orionid. The so-called meteor showers happen when Earth crosses the trail usually left by a comet. There is a rain associated with the dust left by asteroid, but the major causes of this phenomenon are comets.

When a comet approaches the Sun, their volatile material enters into a process of evaporation, which leads to the coma and the dust tail. This causes the dust particles and small grains to be left in space. This material orbit the Sun and, eventually, the Earth passes through this trail of dust. The grains entering the atmosphere produce the so-called meteor showers.

During a meteor shower we see that all meteors seem to come from a specific point in the sky that we call the radiant. The constellation where the radiant is located gives name to the rain. The radiant of the shower we have these days, Orionid, is in the constellation of Orion, the great hunter, where are the super famous Orion’s Belt, known in Latin America as The Three Marys.

The maximum activity of this Orionid should happen in october 22, with between 15 and 20 meteors per hour. But since yesterday and until a few nights after october 22 you can see the meteor shower. So if you missed an opportunity because of a cloudy sky, or because you sleept, try the following night.

The trick is to look for Orionid is to find Orion, maybe searching for Orio’ns Belt. Once you find it, keep the vision in that region of the sky, and enjoy!

In addition to this shower happens in the famous constellation of Orion, easily seen here in the Southern Hemisphere because it contains the famous group of stars called Orion’s Belt, the Orionid are caused by dust left by the famous Halley’s Comet, which makes a complete revolution around the Sun about 76 years.

UARS seen from Discovery soon after its launch.

Finally, NASA announced the fall of satellites UARS (Upper Atmosphere Research Satellite). It happened between 3h23m and 52h09m (GMT) over the Pacific Ocean without a more specific location known.

The satellite was launched in 1991 by the Discovery space shuttle and its mission was to understand the chemistry of the upper layers of the atmosphere. It was deactivated in 2005, and NASA lost all contact with the satellite, so that their destruction in the atmosphere could not be done in a controlled manner.

The good news was that it would probably be destroyed in the path, and the bad new wast that some pieces could  reach the sea level. Despite the mass of the UARS be about 530Kg, no mass with that value could come from the sky, but it would still be worrying if some piece reaches a populated area.

The chances of one of these pieces fall into someone’s head have been estimated at 1 in 3200 (calculated by NASA itself). Well … it would have been easier to win a piece of UARS in mind that winning the Megassena, a popular Lottery in Brazil, whose probability is about one in fifty million (for a single try).

Well, UARS has fallen, not sure where, but certainly nobody was hurt. Falling debris of satellites are not exactly common, but are also not exactly rare. Although the majority of space junk surrounding the Earth is composed of small parts, with a few inches long, larger objects such as UARS are also part of human pollution that extends above the Earth’s atmosphere.

Galileo Galilei (1564–1642). Portrait by Justus Sustermans (1636). National Maritime Museum, Greenwich, London.

“You cannot teach a man anything, you can only help him to find it for himself.” (Galileo Galilei)

Galileo Galilei was an Italian astronomer,  physicist, philosopher and mathematician.
 

Artist concept of Kepler-16 system, showing the planet Kepler-16b and the binary system it revolves around.

It was speculated and now it is observed. Many thing in Astronomy happened this way, first we speculate the existence, with or without the support of mathematics, and then we observe it. It was like that with the expansion of the Universe and  with the existence of planets orbiting a double star system.

The Kepler mission aims to discover extrasolar planets, and it’s accuracy allows to observe Earth-sized planets. Before the mission, one could only observe planets comparable to the size and mass of Jupiter. Kepler is a space telescope, which revolves around the Sun in an orbit almost identical to that of Earth. In one of his most interesting findings, the mission found a planet orbiting a double star system.

This observation shows that, indeed, planets can form around double stars. And, since most stars in our galaxy belong to double star systems, it is something very encouraging to know, concerning the search for possible inhabited planets.

The planet, that received the catalog name Kepler-16b, orbits the Kepler-16 system, and is about 200 light years from us. The distance was inferred by analysis of the magnitude of the brightest star.

The discovery was made by observing the brightness variations of the system, with a plot that we call light curve, that shows the brightness variation as a function of time. This type of plot is widely used in astronomy. The figure below shows the light curve of Kepler-16. The brightest star is the Star A, the fainter star is Star B, and the planet was called Planet B – the difference between the star Kepler-16B and the planet Kepler-16b is the uppercase “b” for the star and lowercase for the planet. The number 1 on the vertical axis of the plot indicates the brightness of the system without eclipse or transit. Click the image to see it enlarged in another window or tab (depending on the configuration of your internet browser).

When the Star B, passes in front of the Star A, the brightness of the system decreases, falling from 1 to about 0.84, as shown in the first graph in the bottom of the figure. When the opposite occurs, and the Star A passes in front of the Star B, the brightness drops less, leaving 1 to about 0.985 as shown in the second graphics in yellow. The transits of the planet in front of the two stars produce brightness variations even more subtle, making the brightness of the system to drop to around 0.987 when it passes in front of the Star A and to about 0.999 as it passes in front of Star B.

Comparison between the estimated size of the star Kepler-16A and the Sun, and between the estimated size of Kepler-16b, Earth and Jupiter (from http://kepler.nasa.gov/Mission/discoveries/kepler16b/).

Kepler-16b makes a complete revolution around its two stars in about 229 days and is a little smaller than Jupiter, with mass similar to that of Saturn.

This size of a planet is much greater than the size that can be identified by Kepler mission, but this finding is important because it shows that there are planets around binary systems.

Kepler-16b has been informally called by astronomers of Tatooine, the planet where Luke Skywalker and Anakin Skywalker, characters from the Star Wars movie, were born. In one of the films is shown a landscape of Tatooine, during the day, with two big stars, like two suns in the sky.

Science fiction and science always go hand in hand!

To read more about Kepler-16b, I suggest the following sites:

Matter in the New York Times  – http://www.nytimes.com/2011/09/16/science/space/16planet.html?_r=1

Web site page about Kepler Mission Kepler-16  – http://kepler.nasa.gov/Mission/discoveries/kepler16b/

Information about NASA’s Kepler-16b  – http://science.nasa.gov/science-news/science-at-nasa/2011/15sep_doublesuns/

Original Title:

This movie has one of the cinema’s most favorite links with astronomy: a disaster caused by the impact of a huge object with Earth. And the catastrophe in this case is nothing less than the total destruction of Earth. But very different from other movies by Hollywood, Melancholia does not portray the drama from an impersonal, global, point of view, exploring the effect of an imminent end of the world over all the people on the planet. In contrast, it focuses on the human drama of a family group before and during an imminent impact.

It is a beautiful film and got a nice finesse. The different personalities evolve gradually from before any suspicion of a tragedy to the time when they are  sure about it. This was the second film I watched by von Trier, the other one was the Antichrist (which has no astronomical detail, and I will not comment here on the blog), and both have aesthetic similarities as division into chapters and an introduction that seeks to convey part of the psychological atmosphere of the film. The scenes are beautiful, showing the director’s concern about the photography.

It’s a movie that should be watched, especially because of the use of the end of the world only as a background to explore the human psyche.

And the Astronomical poetic licenses of the film are perfectly acceptable. This should serve as an example to many science fiction and disaster movies from Hollywood.

An astronomical detail that caught my attention was the character of Kiefer Sutherland, the amateur astronomer of the family, confusing the star Antares in the Scorpio constellation, with an object on a collision course with Earth. For more reddish, like Antares, and visually closer to Antares, anyone a little bit familiar with the sky would never commit such a mess. A poetic license, as I said, perfectly acceptable.

Another detail is that the object, called Melancholia, is large and therefore rounded. This was an interesting detail, well done! He put a big object to collide with Earth and, in general, large objects added enough mass to its gravitational force to produce the rounded form, very different from most of the comets and asteroids. Cool, one point to the film, because of the concern about the scientific quality! But, on the other hand, it is impossible that such a massive object in the solar system be unknown to astronomers until a short time before impact. Well … there, the concern with the scientific quality left much to be desired … Lets consider a tie, then!

Lars von Trier

Lars von Trier looks like a guy who needs to learn to be careful about what he says or should think a little bit more before speaking. He was banished, with much justice, from Cannes Festival by quotations Nazis. After that, he apologized and tried to make a good policy to Cannes. Trier remained banned, but his films can still participate in the festival. This, perhaps, is not surprising coming from a guy who has a foul word with 4 letter, which begins with ‘F’ and ends with ‘K’, tattooed on proximal phalanges pinky finger, ring, middle and right index finger.

This is a guy whose work I like too much, but whose personality is not the nicest.

Four images from a computer simulation showing the collision between the moon and a smaller body. The latter is spread in part of the lunar surface, giving rise to the mountainous geography. (M. Jutzi e E. Asphaug, Nature).

It is possible that the Earth has already had two moons. A paper published on August 4, 2011, issue of Nature (see the abstract here), suggests that the impact that gave birth to our moon would have also given rise to another body.

The most accepted theory about the formation of the Moon says that an object about the size of Mars collided with the Earth in the early solar system, about 4 billion years ago, and the resulting fragments were added to form our satellite. But the moon is strangely very asymmetric. The portion of the surface facing us is quite different from the so-called dark side, never seen by us. While the face we see is dominated plains of solidified lava, the lunar maria, the dark side is dominated by mountainous terrain.

If the fragments of the impact that formed the Moon gave rise also another smaller object, this may have collided with our most famous Moon and spread over the surface, explaining the mountainous part of our satellite. The smaller object would have 1 / 3 the size of our current and only natural satellite.

To try to shed more light on the issue, will begin the GRAIL mission, Gravity Recovery And Interior Laboratory. Your goal is to map the moon’s gravitational field and thus allow us to better understand the distribution of matter. This could give us more clues about an old fellow who could adhered to our Moon

The launch of the GRAIL mission is scheduled for the morning of Saturday, September 10.

To read more:

NASA site about GRAIL mission and the two moons theory – http://science.nasa.gov/science-news/science-at-nasa/2011/07sep_twomoons/

Computer simulation about the two moons – http://news.ucsc.edu/2011/08/big-splat.html

GRAIL mission site – http://moon.mit.edu/overview.html

News about the GRAIL launch – http://www.nasa.gov/mission_pages/grail/main/index.html

Model representing James Webb Telescope.

The James Webb Space Telescope, Hubble’s successor, is an infrared telescope. Warm materials glow in the infrared, and for this reason Webb optics have to be kept cold — all the way down to 40 Kelvin (or -233^°C or -388°F). Unfortunately, our technology doesn’t allow us to polish mirrors while working at 40K. Thus, the conundrum for Webb was that the mirrors had to be polished at ordinary temperatures but still had to be the right shape at 40K. When temperatures change so dramatically, mirrors warp and deform.

About ten years ago, a study took place to select the best material for the Webb mirrors. Instead of glass, we decided to use a substance called Beryllium. We found that by using computer models, we could accurately predict the ways Beryllium would deform. The plan was to polish the eighteen mirror segments that make up our primary mirror at a warm temperature, but give them exactly the wrong shape that would deform into the right shape once they were brought down to 40K.

It sounds like a bold plan and, while confident in our testing, we were all a bit concerned about whether this would work well and on the first try. One can always try again — but this entails extra cost and delays, so we were hoping to avoid it.

Finally, in January 2010, the first demonstration mirror segment for Webb went through the full polishing process and was frozen to 40K at the X-ray and Cryogenic Facility at the Marshal Space Flight Center in Huntsville, Ala. We measured the segment at the end, and found it had deformed to the right shape. This is a major success for the Webb project and lets us move on to developing the rest of the primary mirror segments.

Part of the set of mirros that will form the James Webb's primary mirror.

Comparision between James Webb's primary mirror with Hubble's primary mirror.

And, its pictures were unmistakably out of this world. This brand new Hubble photo is of a small portion of one of the largest seen star-birth regions in the galaxy, the Carina Nebula. Towers of cool hydrogen laced with dust rise from the wall of the nebula. The scene is reminiscent of Hubble’s classic “Pillars of Creation” photo from 1995, but is even more striking in appearance. The image captures the top of a three-light-year-tall pillar of gas and dust that is being eaten away by the brilliant light from nearby bright stars. The pillar is also being pushed apart from within, as infant stars buried inside it fire off jets of gas that can be seen streaming from towering peaks like arrows sailing through the air.

NASA and the Space Telescope Science Institute (STScI) are celebrating Hubble’s journey of exploration with this stunning new picture, online educational activities, an opportunity for people to explore galaxies as armchair scientists, and an opportunity for astronomy enthusiasts to send in their own personal greetings to Hubble for posterity.

Unfortunately, the Hubble is nearing the end of its useful life, and the bus has left space for the last time to perform maintenance. Now we must wait for the staging of new space telescope in 2014.

Carina Nebula, by Hubble.

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