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Posts Tagged ‘Astronomy’

Billions Of Earth-Like Planets In Our Galaxy

June 3rd, 2010 No comments

Extrasolar-PlanetsIt is worth remembering that our galaxy alone has billions of Earth-like planets, and these earths are “[not only] probably habitable but they probably are also going to be inhabited”

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Galaxy has ‘billions of Earths’

There could be one hundred billion Earth-like planets in our galaxy, a US conference has heard.

Dr Alan Boss of the Carnegie Institution of Science said many of these worlds could be inhabited by simple lifeforms.

He was speaking at the annual meeting of the American Association for the Advancement of Science in Chicago.

So far, telescopes have been able to detect just over 300 planets outside our Solar System.

But, based on the limited numbers of planets found so far, Dr Boss has estimated that each Sun-like star has on average one “Earth-like” planet.

This simple calculation means there would be huge numbers capable of supporting life.

Not only are they probably habitable but they probably are also going to be inhabited,” Dr Boss told BBC News. “But I think that most likely the nearby ‘Earths’ are going to be inhabited with things which are perhaps more common to what Earth was like three or four billion years ago.” That means bacterial lifeforms.

Source: http://news.bbc.co.uk/2/hi/7891132.stm

The caption below was written in November 2004.

Other Earths

So, after having compiled a bestiary of exotic planets, many the size of Jupiter and locked in a deadly embrace with their star, what are the chances of the planet-hunters identifying rather smaller, sedate rocks upon which life might actually get the chance to evolve? It’s not as if these planets are likely to exist in minute numbers: current estimates [Using the Drake Equation] border on there being 30 billion terrestrial planets in our Galaxy alone [this is an article from 2002]. The odds of finding such planets lengthen a lot when one considers that these planets would have longer years and cause much smaller wobbles in their star’s position.

The odds shorten again the longer we look for these planets. Hot Jupiters tend to get found simply because the radial velocity method is most sensitive to their kind. It’s only now that smaller planets are being found, although none of them are likely to harbour life. Adopt a different method of detection, and we might start to see terrestrial planets, instead of inferring their presence.

This is precisely what the Terrestrial Planet Finder (TPF) telescope is designed to do. This instrument comprises four space-based telescopes flying in formation. Their light is combined in such a way as to vastly increase resolution. One of the indicators that TPF will be looking for is the presence of elemental oxygen in a planet’s atmosphere. All oxygen in our atmosphere is there because of photosynthetic organisms: plants and cyanobacteria. Oxygen is therefore a key signature of life6.

TPF is not due to fly until 2015 at the earliest. In the meantime, Earth-based telescopes will get bigger and better, and astronomers will be able to observe for longer wobbles than they currently can. Even if we can’t see the little green men yet, we’ll have a much better idea of where they might live.

Source: H2G2 extrasolar planet hunting

Read more…

NASA’s New Eye on the Sun Delivers Stunning First Images

April 27th, 2010 No comments


446589main_fulldiskmulticolor-orig_fullFrom time to time I come across technology or space-related information that I feel would fit nicely with the larger mission of this website. This one is really pretty and awe inspiring, but what isn’t awe inspiring in nature?

Recently, the NASA Solar Dynamics Observatory (SDO) took its first photographs of the sun. Click on the fascinating image to the right to see it in a larger size.

Bellow is a caption of the NASA article.

Title: NASA’s New Eye on the Sun Delivers Stunning First Images – 04.21.10

NASA’s recently launched Solar Dynamics Observatory, or SDO, is returning early images that confirm an unprecedented new capability for scientists to better understand our sun’s dynamic processes. These solar activities affect everything on Earth.

Some of the images from the spacecraft show never-before-seen detail of material streaming outward and away from sunspots. Others show extreme close-ups of activity on the sun’s surface. The spacecraft also has made the first high-resolution measurements of solar flares in a broad range of extreme ultraviolet wavelengths.

“These initial images show a dynamic sun that I had never seen in more than 40 years of solar research,” said Richard Fisher, director of the Heliophysics Division at NASA Headquarters in Washington. “SDO will change our understanding of the sun and its processes, which affect our lives and society. This mission will have a huge impact on science, similar to the impact of the Hubble Space Telescope on modern astrophysics.”

A full-disk multiwavelength extreme ultraviolet image of the sun taken by SDO on March 30, 2010. False colors trace different gas temperatures. Reds are relatively cool (about 60,000 Kelvin, or 107,540 F); blues and greens are hotter (greater than 1 million Kelvin, or 1,799,540 F). Credit: NASA/Goddard/SDO AIA Team

Launched on Feb. 11, 2010, SDO is the most advanced spacecraft ever designed to study the sun. During its five-year mission, it will examine the sun’s magnetic field and also provide a better understanding of the role the sun plays in Earth’s atmospheric chemistry and climate. Since launch, engineers have been conducting testing and verification of the spacecraft’s components. Now fully operational, SDO will provide images with clarity 10 times better than high-definition television and will return more comprehensive science data faster than any other solar observing spacecraft.

Source: http://www.nasa.gov/mission_pages/sdo/news/first-light.html

For more on the SDO mission, visit http://www.nasa.gov/sdo

New Sun Spots 2010-02-07

February 7th, 2010 No comments

New sunspots just appeared, known as sunspot group 1045. This is an active region that has produced moderate (M-class) solar flares. Here’s a photo of the sun
2010-02-07-sunspots
You can find a LIVE photo of the sun if you scroll down and look in the right side of this website

New Sun Spots 2009-09-22

September 22nd, 2009 No comments

I keep my eye on our nearest star out of curiosity. You also can follow the sun, find the live picture of the sun in the lower right bar, do it, scroll down now.

Today, I saw new sun spots, 3 of them:

New-Sun-Spots09-22-2009(click image to enlarge)