A recent scientific discovery, in a paper titled "A New Gravitational Wave Verification Source," has been made of a what is known as a binary white dwarf system. Phil Plais, blogger and astronomer, explains that this system, named WD 0931 +444, consists of two white dwarves (very dense matter left over from the death of a star) which are in orbit around each other. Using a spectrograph, a device which splits light into its individual colors, astronomers have calculated that the time it takes for the stars to orbit each other is a mere 20 minutes, a speed of 300 km/s. Because of such speed and because they are so close together (they are separated by 130,000 km), they undergo a phenomenon predicted by Albert Einstein: the emission of gravitational waves. Any two bodies orbiting each other emit release energy in the form of ripples in space, causing any object in its path to expand and contract. Unfortunately, most gravitational waves are extremely weak, since the energy of the waves is taken from the kinetic and potential energy of the system. However, as Plait states, "when [these bodies] are very massive and moving very quickly, the waves are stronger." As such, the strength of the emitted gravitational waves from WD 0931 +444 may actually be enough for astronomers to detect. A possible space mission is being planned for the year 2034 called eLISA (evolved Laser Interferometry Space Antenna) to send three spacecrafts, with special equipment that uses lasers to detect any change in each other's position, near this system to attempt to detect these gravitational waves.
Phil Plait demonstrates the grasp he has on the content by conveying it to the reader in a simplified, abbreviated manner that informs about the topic without having to resort to many scientific terms or jargon. His tone throughout the article is one of enthusiasm, which serves to keep the reader engaged in the reading. This is often a good strategy when talking about a subject that may be foreign or unappealing to most (such as a pair of stars spinning around each other). This enthusiasm is shown by emphasizing or italicizing words to amplify his intonation of such words. Also, there are occasions in which he uses a language device known as hypophora, where the speaker asks and then answers his own question. This method serves to bring the reader into the author's perspective, revealing what questions the author has and then promptly answering them. Being an informative article, there is no real argumentation presented by the author. The only opinionative comment he makes is in the end of the article, when referring to the wonder of this discovery and of the future space mission: "I really do love this stuff." However, he does hold a positive and hopeful attitude when talking about the possibility of the eLISA space mission, suggesting he supports and believes in the scientific potential of this mission. Overall, his enthusiastic, uncomplicated manner of writing proved very effective, as it was engaging and fascinating, while still easy to understand.
http://www.slate.com/blogs/bad_astronomy/2014/07/02/gravitational_waves_orbiting_white_dwarfs_provide_good_test_of_einstein.html
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