stars locations are uncertain

8/7/2019 Stars Locations are Uncertain

1/7


2/7

of a star, according to the researchers.

A material with negative index of refraction transmits light or other wave energy differently thanone with positive index of refraction. In all natural materials, when an energy beam light, radar,microwave passes through water or glass or some other material, the beam is displaced inthe same direction. The amount of displacement depends upon how much the material slowsthe speed of the beam. In negative phase velocity media, the displacement is in the oppositedirection.

Lakhtakia and Tom. G. Mackay, lecturer in Mathematics, University of Edinburgh decided tolook at why the permittivity and permeability had to be less than zero. They found that one orboth permeability and permittivity could be less than zero and negative phase velocity wouldoccur. They then found that both could be greater than zero and a negative index of refractionwould occur but only when special relativity came into play.

The researchers looked at transmission through space, where high velocities are common.

"First I did the derivations with the observer moving and the energy source stationary," says

Lakhtakia. " Then Mackay did the derivations with the observer stationary and the light sourcemoving."

What they found was that it depends on the state of the observer whether any particular mediaat any time has negative or positive index of refraction. The relative velocity of the observerchanges the index of any material.

"Light coming off a stellar object passes through many different regions of space filled withdifferent media and is affected by different gravitational fields," says Lakhtakia. "When we finallysee it, we cannot really know where it originated."

While this may be of no consequence today, Lakhtakia believes it has important implications forwhen space travel is common. Because this is a direction dependent effect, it will change thetelemetry of objects and spacecraft.

"The business of space navigation and interpreting star maps could be a lot more complicatedthan we now think it is," says Lakhtakia. "Imagine mining of extrasolar asteroids. We might notwant to send humans to do the mining, but robots would have to know where the asteroid is andwhere on its surface to mine when it left our solar system."

Calculations would need to be made from Earth on an asteroid that might not be where wevisually see it. The effects of negative phase velocity media would need to be taken intoconsideration.

Another problem would be navigating from somewhere far away from the Earth in a space shipusing information gathered from the Earth. Depending on the velocity of the spacecraft and theobject aimed for, negative phase velocity media between the spacecraft and the destinationwould also need to be considered.

Source: Penn State

0 view popularsend feedback to editors3 /5 (2 votes)


http://www.physorg.com/news691.html 2/7


3/7

12345

Please registerorsign in to add a comment. Registration is free, and takes less than a minute.Read more

Sign in with

Email

Password

Sign In

Forgot your password? Click here to reset it.

Notify me via email of follow-up comments posted here sign in first

print

email

save as pdf

add to blog

bookmark

send feedback

font size




4/7

Rank :

12345

3 /5 (2 votes)Tags

Related Stories

Scientists reverse Doppler Effect Mar 07, 2011 | not rated yet | 0Comprehensive schools do not reduce social mobility Mar 04, 2011 | not rated yet |0Facebook walls boost self-esteem, finds study Mar 02, 2011 | not rated yet | 0No flaw safe from Montreal's game glitch hunters Mar 01, 2011 | not rated yet | 0Quasar's belch solves longstanding mystery (w/ Video) Feb 24, 2011 | not rated yet |

0

FeaturedVideoLast commentsPopularMost sharedPartners

Quantum no-hiding theorem experimentally confirmed for first time Mar 07, 2011 | 4.7/ 5 (16) | 15Could the combination of general relativity and quantum mechanics lead to spintronics?Mar 03, 2011 | 4.7 / 5 (25) | 8Fast tunable coupler could lead to better quantum computing models Mar 02, 2011 | 5/ 5 (4) | 0Time travel experiment demonstrates how to avoid the grandfather paradox (Update)Mar 01, 2011 | 4.5 / 5 (32) | 81Scientists make single-mode laser out of a single nanowire Feb 28, 2011 | 4.6 / 5

(10) | 4more news

More news stories

Shuttle Discovery approaches Earth for last landing

The oldest and most traveled space shuttle, Discovery, is headed for its lastlanding on Earth Wednesday before becoming the first of three to retire in a USmuseum.

Space & Earth / Space Exploration

37 minutes ago | 4 / 5 (1) | 0




5/7

Baby stars born to 'napping' parents

(PhysOrg.com) -- Cardiff University astronomers believe that a young star's long"napping" could trigger the formation of a second generation of smaller stars andplanets orbiting around it.

Space & Earth / Astronomy

25 minutes ago | not rated yet | 0 |

NASA infrared satellite data sees system 96P developing tropically

near Vanuatu

The low pressure area called System 96P in the South Pacific appears to begetting organized in infrared satellite imagery from NASA. System 96P is showingsigns of strong convection and that has prompted ...

Space & Earth / Earth Sciences

21 minutes ago | not rated yet | 0

Polar ice adding more to rising seas: study

(PhysOrg.com) -- The Greenland and Antarctic ice sheets are losing mass at anaccelerating pace, according to a new NASA-funded satellite study. The findingsof the study -- the longest to date of changes ...

Space & Earth / Earth Sciences

7 hours ago | 4 / 5 (8) | 16 |

James Webb Space Telescope's 'chassis' gets taken out for a spin at

NASA

The Integrated Science Instrument Module, or ISIM, is the structural heart of theJames Webb Space Telescope, what engineers call the main payload. It willhouse the four main scientific instruments of the ...

Space & Earth / Space Exploration

1 hour ago | not rated yet | 0

Super sense of smell not innate

World-class "noses" in the perfume and wine business are not born with an outsized sense ofsmell but acquire it through years of professional sniffing, according to new research.

Cigarettes to vanish from shelves in England

Cigarettes will disappear under the tobacconist's counter from next year in England under new




6/7

measures announced Wednesday.

Which side of the brain rotates a mental picture?

Consider the simple situation in which you are walking around the kitchen and decide to pick upyour own cup of tea, which is identical to others lying on the table. Your brain chooses thecorrect cup of tea by using different ...

Protein study helps shape understanding of body forms

Scientists have shed light on why some people are apple-shaped and others are pear-shaped.

Aspirin's ability to protect against colorectal cancer may depend on inflammatory

pathways

The reduced risk of colorectal cancer associated with taking aspirin or other nonsteroidal anti-

inflammatory drugs (NSAIDs) may be confined to individuals already at risk because ofelevations in a particular inflammatory ...

Reading in two colours at the same time

The Nobel prize-winning physicist Richard Feynman once wrote in his autobiographical book(What do you care what other people think?): "When I see equations, I see letters in colors - Idon't know why [...] And I wonder what t ...

top

HomeSearch

HelpWhat's newAbout usContact / FAQPartners

PhysOrg Account

Sponsored AccountNewsletterRSS feeds

iPhoneiPad AppsBlackberry AppAndroid App&WidgetAmazon KindlePDA version

Feature StoriesWeblog & ReportsPodcastsArchive




7/7

FacebookTwitter

PhysOrg.com 2003-2011 Privacy Policy | Terms of Use



stars locations are uncertain

Documents