Skip to main content

Measuring Distances To Stars Just Got A Whole Lot Easier Thanks To This "Stellar Twin" Trick

Measuring Distances To Stars Just Got A Whole Lot Easier Thanks To This "Stellar Twin" Trick

September 4, 2015 | by Jonathan O'Callaghan
Artist's impression of two stars.
Photo credit: RealCG Animation Studio. Shutterstock.
Scientists have developed a novel method to calculate the distances to stars, and it could be useful in helping map the size of galaxies. The study is published in the Monthly Notices of the Royal Astronomical Society.
The researchers from the University of Cambridge examined what are known as “stellar twins.” These are stars that are identical, with exactly the same chemical composition, which can be worked out from their spectra – the type of light they emit. If they were both placed at the same distance from Earth, they would shine with equal brightness.
So the team realized that if the distance to just one of the stars was known, the other could be calculated relatively easily based on how brightly it was shining. The dimmer it is, the further away it is, and vice versa. The method can be used to accurately measure the distance.
"It's a remarkably simple idea – so simple that it's hard to believe no one thought of it before," said lead author Dr Paula Jofre Pfeil, from Cambridge’s Institute of Astronomy, in a statement. "The further away a star is, the fainter it appears in the sky, and so if two stars have identical spectra, we can use the difference in brightness to calculate the distance."

The method relies on two stars with identical spectra. Carolina Jofré.
Usually, distances to stars are measured using the parallax method. This essentially involves looking at a star from two different positions on Earth. By measuring the distance between those two locations, and their angle of inclination to the star, its distance from Earth can be measured.
But the parallax method is only useful for stars within 1,600 light-years, as if they are further then the angle of inclination is too small to be measured. This makes the new method incredibly useful in working out the distances to stars much farther away.
At the moment, the distances to remote stars are measured by using models that calculate their brightness. These models are fairly inaccurate though, with an error as high as 30%. This new method greatly reduces that inaccuracy. And it could also help better measure the size of galaxies, by calculating the distances to different stellar twins at a galaxy’s extremes.
"Determining distances is a key problem in astronomy, because unless we know how far away a star or group of stars is, it is impossible to know the size of the galaxy or understand how it formed and evolved," added Pfeil in the statement. "Every time we make an accurate distance measurement, we take another step on the cosmic distance ladder."

Popular posts from this blog

camtasia 9 key

1.abul hossain Key : BBCUV-UVDRC-M8C5S-CHMX7-2M3A5 2.YR-Invasion Key=BBCUVUVDRCM8C5SCHMX72M3A5

Hidden Wiki

Welcome to The Hidden WikiNew hidden wiki url 2015 http://zqktlwi4fecvo6ri.onion Add it to bookmarks and spread it!!!
Editor's picks Bored? Pick a random page from the article index and replace one of these slots with it.
The Matrix - Very nice to read. How to Exit the Matrix - Learn how to Protect yourself and your rights, online and off. Verifying PGP signatures - A short and simple how-to guide. In Praise Of Hawala - Anonymous informal value transfer system. Volunteer Here are five different things that you can help us out with.
Plunder other hidden service lists for links and place them here! File the SnapBBSIndex links wherever they go. Set external links to HTTPS where available, good certificate, and same content. Care to start recording onionland's history? Check out Onionland's Museum Perform Dead Services Duties. Introduction PointsAhmia.fi - Clearnet search engine for Tor Hidden Services (allows you to add new sites to its database). DuckDuckGo - A Hidden S…

[SOLVED] IDM WAS REGISTERED WITH A FAKE SERIAL NUMBER

[SOLVED] IDM WAS REGISTERED WITH A FAKE SERIAL NUMBER
Good News [May 08, 2015]: IDM developers got smarter, but the crackers are always a step ahead. Follow this article and send an email to [email protected] if you are desperate. I can NOT post any crack here for legal reasons. Happy Downloading with IDM. ;) *********** first tip is to use latest crack for idm from  onhax.net idm universal web crack and make sure u are using all latest vers I am sure many of us are too much dependent on Internet Download Manager a.k.a. IDM. The main reason didn’t permanently switch to linux was IDM. I mainly use it for batch downloading and download streaming videos. Till yesterday, IDM was working fine with me (of course with fake serial numbers, keygen, crack, patch etc. which could be found with little effort). But few days ago, with the latest update version 6.18 build 7 (released on Nov 09, 2013) Internet Download Manager was literally had a breakthrough and crushed all the serial numbers, …