Science Current Events | Science News | Brightsurf.com
 

Optical vortex could look directly at extrasolar planets

December 01, 2005
A new optical device might allow astronomers to view extrasolar planets directly without the annoying glare of the parent star. It would do this by "nulling" out the light of the parent star by exploiting its wave nature, leaving the reflected light from the nearby planet to be observed in space-based detectors. The device, called an optical vortex coronagraph, is described in the December 15, 2005 issue of Optics Letters.

About ten years ago the presence of planets around stars other than our sun was first deduced by the very tiny wobble in the star's spectrum of light imposed by the mutual tug between the star and its satellite. Since then more than 100 extrasolar planets have been detected in this way. Also, in a few cases the slight diminution in the star's radiation caused by the transit of the planet across in front of the star has been observed.

Many astronomers would, however, like to view the planet directly-a difficult thing to do. Seeing the planet next to its bright star has been compared to trying to discern, from a hundred meters away, the light of a match held up next to the glare of an automobile's headlight. The approach taken by Grover Swartzlander and his colleagues at the University of Arizona is to eliminate the star's light by sending it through a special helical-shaped mask, a sort of lens whose geometry resembles that of a spiral staircase turned on its side.

The process works in the following way: light passing through the thicker and central part of the mask is slowed down. Because of the graduated shape of the glass, an "optical vortex" is created: the light coming along the axis of the mask is, in effect, spun out of the image. It is nulled, as if an opaque mask had been place across the image of the star, but leaving the light from the nearby planet unaffected.

The idea of an optical vortex has been around for many years, but it has never been applied to astronomy before. In lab trials of the optical vortex mask, light from mock stars has been reduced by factors of 100 to 1000, while light from a nearby "planet" was unaffected (see test figures at http://www.aip.org/png/2005/241.htm). Attaching their device to a telescope on Mt. Lemon outside Tucson, Arizona, the researchers took pictures of Saturn and its nearby rings to demonstrate the ease of integrating the mask into a telescopic imaging system.

This is, according to Swartzlander (grovers@optics.arizona.edu, 520-626-3723), a more practical technique than merely attempting to cover over the star's image, as is done in coronagraphs, devices for observing our sun's corona by masking out the disk of the sun. It could fully come into its own on a project like the Terrestrial Planet Finder, or TPF, a proposed orbiting telescope to be developed over the coming decade and designed to image exoplanets.

American Institute of Physics


Related Extrasolar Planets Current Events and Extrasolar Planets News Articles


Is salt the key to unlocking the interiors of Neptune and Uranus?
The interiors of several of our Solar System's planets and moons are icy, and ice has been found on distant extrasolar planets, as well.

Astronomers create array of Earth-like planet models
To sort out the biological intricacies of Earth-like planets, astronomers have developed computer models that examine how ultraviolet radiation from other planets' nearby suns may affect those worlds, according to new research published June 10 in Astrophysical Journal.

New exoplanet too big for its star
The Australian discovery of a strange exoplanet orbiting a small cool star 500 light years away is challenging ideas about how planets form.

Robotically discovering Earth's nearest neighbors
A team of astronomers using ground-based telescopes in Hawaii, California, and Arizona recently discovered a planetary system orbiting a nearby star that is only 54 light-years away.

Tau Ceti: The next Earth? Probably not
As the search continues for Earth-size planets orbiting at just the right distance from their star, a region termed the habitable zone, the number of potentially life-supporting planets grows.

Colorful life-form catalog will help discern if we're alone
While looking for life on planets beyond our own solar system, a group of international scientists has created a colorful catalog containing reflection signatures of Earth life forms that might be found on planet surfaces throughout the cosmic hinterlands.

ALMA finds double star with weird and wild planet-forming discs
From movies to television, obesity is still considered "fair game" for jokes and ridicule. A new study from researchers at Bowling Green State University took a closer look at weight-related humor to see if anti-fat attitudes played into a person's appreciation or distaste for fat humor in the media.

Astronomers identify signature of Earth-eating stars
Some Sun-like stars are 'Earth-eaters.' During their development they ingest large amounts of the rocky material from which 'terrestrial' planets like Earth, Mars and Venus are made.

Giant telescope tackles orbit and size of exoplanet
Using one of the world's largest telescopes, a Lawrence Livermore team and international collaborators have tracked the orbit of a planet at least four times the size of Jupiter.

Lick's Automated Planet Finder: First robotic telescope for planet hunters
Lick Observatory's newest telescope, the Automated Planet Finder (APF), has been operating robotically night after night on Mt. Hamilton since January, searching nearby stars for Earth-sized planets.
More Extrasolar Planets Current Events and Extrasolar Planets News Articles

Extrasolar Planets and Astrobiology

Extrasolar Planets and Astrobiology
by Caleb Scharf (Author)


Winner of the 2011 Chambliss Prize for Astronomical Writing from The American Astronomical Society!

This book offers an advanced introduction to the increasingly robust fields of extrasolar planets and astrobiology. No other text currently available applies this level of mathematics and physics, while also providing an extensive grounding in key issues of chemistry, biology, and geophysics. With extensive references to the literature and chapter-ending exercises, this book can be used as the core text for teaching undergraduate or introductory graduate level courses. The text will also provide astrobiologists with an indispensable "User's Manual" when quick reference to key mathematical and physical techniques is needed. A continually updated online component, fully cross...

The Planets

The Planets
by Dava Sobel (Author)


With her bestsellers Longitude and Galileo's Daughter, Dava Sobel introduced readers to her rare gift for weaving complex scientific concepts into a compelling narrative. Now Sobel brings her full talents to bear on what is perhaps her most ambitious topic to date-the planets of our solar system. Sobel explores the origins and oddities of the planets through the lens of popular culture, from astrology, mythology, and science fiction to art, music, poetry, biography, and history. Written in her characteristically graceful prose, The Planets is a stunningly original celebration of our solar system and offers a distinctive view of our place in the universe.

* A New York Times extended bestseller
* A Featured Alternate of the Book-of-the-Month Club, History Book Club, Scientific...

Extrasolar Planets: A Catalog of Discoveries in Other Star Systems

Extrasolar Planets: A Catalog of Discoveries in Other Star Systems
by Terry L. Kepner (Author)


Astronomers have long looked in vain for evidence of worlds orbiting other stars, but technological advances have made such discoveries far more regular. Several teams continuously work on the planet search using a variety of techniques and equipment; as a result, we know of 161 planetary candidates in 135 star systems, from 8.25 to 9,000 light-years from Earth.

This work summarizes information on all the extrasolar planets discovered. Each planet is described in as much detail as is available with graphs indicating how the planet orbits its primary. Details on the primary are given. Additionally, the boundaries of the habitability zone around each star are plotted, and information about the likelihood of terrestrial planets existing in each system is provided. Five appendices are...

Scholastic Discover More Reader Level 1: Planets (Scholastic Discover More Readers)

Scholastic Discover More Reader Level 1: Planets (Scholastic Discover More Readers)
by Gail Tuchman (Author)


A level 1 reader in the Scholastic Discover More Reader series.

PLANETS guides beginning readers on a journey of exploration through the solar system, showing how planets were formed, their attraction to stars, moons, and satellites, and how we humans explore our space neighborhood--the Milky Way galaxy--and beyond. A companion digital book poses evidence-based questions through fun Q&A, matching games, writing activities, and vocabulary "slams" that test the reader's comprehension.

13 Planets: The Latest View of the Solar System (National Geographic Kids)

13 Planets: The Latest View of the Solar System (National Geographic Kids)
by David A. Aguilar (Author)


First, Pluto left. Then it came back, along with Ceres and Eris...and now Haumea and MakeMake, too! The recent actions of the International Astronomical Union have put every solar system book out of date. In response, National Geographic joins forces with David Aguilar of the Harvard Smithsonian Astronomical Observatory to revise our 2008 book—and to update young readers on the high-interest topic of space. Using simple text and spectacular photorealistic computer art by the author, this book profiles all 13 planets in their newly created categories—plus the sun, the Oort Cloud, comets, and other worlds being discovered. Back-of-the-book activities offer hands-on fun for budding astronomers.

Moons of the Solar System: From Giant Ganymede to Dainty Dactyl (Astronomers' Universe)

Moons of the Solar System: From Giant Ganymede to Dainty Dactyl (Astronomers' Universe)
by James A. Hall III (Author)


This book captures the complex world of planetary moons, which are more diverse than Earth's sole satellite might lead you to believe. New missions continue to find more of these planetary satellites, making an up to date guide more necessary than ever. Why do Mercury and Venus have no moons at all? Earth's  Moon, of course, is covered in the book with highly detailed maps. Then we move outward to the moons of Mars, then on to many of the more notable asteroid moons, and finally to a list of less-notable ones.All the major moons of the gas giant planets are covered in great detail, while the lesser-known satellites of these worlds are also touched on. Readers will learn of the remarkable trans-Neptunian Objects – Pluto, Eris, Sedna, Quaoar –including many of those that have...

The New Worlds: Extrasolar Planets (Springer Praxis Books)

The New Worlds: Extrasolar Planets (Springer Praxis Books)
by Fabienne Casoli (Author), Therese Encrenaz (Author)


Offering an engaging and complete story of the hunt for new worlds, this volume fully details the detection and exploration of extrasolar planets. It examines the very wide range of extrasolar planets that have been discovered during the past ten years and looks at what can be learned about such planets by studying the bodies in our own solar system. It also discusses the formation of planetary systems, the way in which such systems may evolve and the final systems of planets that result. In addition, the authors demonstrate how life might evolve on an extrasolar planet and how such life might be detected.

Extrasolar Planets (Worlds Beyond)

Extrasolar Planets (Worlds Beyond)
by Ron Miller (Author)


Color photographs enhance the explanation and description of our solar system for juveniles.

God's Planet

God's Planet
by Owen Gingerich (Author), Randy Isaac (Foreword)


With exoplanets being discovered daily, Earth is still the only planet we know of that is home to creatures who seek a coherent explanation for the structure, origins, and fate of the universe, and of humanity’s place within it. Today, science and religion are the two major cultural entities on our planet that share this goal of coherent understanding, though their interpretation of evidence differs dramatically. Many scientists look at the known universe and conclude we are here by chance. The renowned astronomer and historian of science Owen Gingerich looks at the same evidence―along with the fact that the universe is comprehensible to our minds―and sees it as proof for the planning and intentions of a Creator-God. He believes that the idea of a universe without God is an...

The Privileged Planet: How Our Place in the Cosmos Is Designed for Discovery

The Privileged Planet: How Our Place in the Cosmos Is Designed for Discovery
by Guillermo Gonzalez (Author), Jay Richards (Author)



Earth. The Final Frontier

Contrary to popular belief, Earth is not an insignificant blip on the universe’s radar. Our world proves anything but average in Guillermo Gonzalez and Jay W. Richards’ The Privileged Planet: How Our Place in the Cosmos Is Designed for Discovery.

But what exactly does Earth bring to the table? How does it prove its worth among numerous planets and constellations in the vastness of the Milky Way? In The Privileged Planet, you’ll learn about the world’s:

life-sustaining capabilities
water and its miraculous makeup
protection by the planetary giants

And how our planet came into existence in the first place.


© 2015 BrightSurf.com