pulsar



The recently announced discovery of the first known planet orbiting a pulsar (the ultra-dense, pulsating remnant off the supernova explosion of a star) turned out to be based on faulty data. Had this discovery been confirmed, theorists would have had difficulty accounting for the existence of such a planet. The supernova would certainly have destroyed any preexisting planets. This particular pulsar is relatively young, allowing little time for a new planet to have coalesced, and it rotates relatively slowly, implying that it has not interacted with any nearby star since the supernova.

But newer evidence of a different pulsar with planets is more promising. This is a rapidly spurring “millisecond pulsar” thought to be a much older object that has pulled gaseous material from a stellar neighbor, causing its rotational speed to increase. Leftover, unconsumed gas around such a pulsar could, in theory, coalesce into planets. Or the pulsar’s radiation might have vaporized a companion star, providing new material for planetary formation.

The recent discovery: planet orbiting a pulsar
if it is true, it would be difficult to find evidence for that
reasons: 1. it is young- existing planets
2. it rotate slowly-not interact with other stars

newer evidence: "millisecond pulsar" 
1. older - pull gaseous from a stellar neighbor
2. unconsumed gas-coalesce into planet
3. pulsar's radiation vaporized a companion star



1. The primary purpose of the passage is to

A. provide an example of the dangers of a recent discovery based on faulty data.
B. illustrate the difficulty of explanation concerning a recent discovery
C. assess the credibility of recent findings concerning the as yet unverified existence of a class of objects.
whether the two proposed idea are suitable for science implication

D. argue that a certain hypothesis fails to account for a seemingly contradictory phenomenon
E. demonstrate how difficult it might be to find out the reality of a phenomenon

2. Which of the following best describe the organization of the passage?

A. Two sets of research findings relating to similar phenomenon are mentioned, and the theoretical implication of each are discussed.
B. A theoretical explanation of a phenomenon is presented and rejected, and a more attractive alternative is offered
C. Two independent and divergent interpretations of a set of observational data are compared and one is favored over the other
D. An example of careless scientific research is introduced and contrasted with a more rigorous analysis of the same material.
E. The state of knowledge of an unexplainable phenomenon is outlined and an approach to further investigation is recommended.

3. Which of the following can be inferred regarding the pulsar discussed in the first paragraph?

A. Theorists initially doubted its existence
B. If its existence had been confirmed, astronomers would and have turned their attention to the pulsar discussed in the second paragraph.
C. If the supernovas explosions that created it had been more powerful, the resulting radiation would have preceded the subsequent formation of a planet.
D. If it had interacted with a nearby star since the supernova explosion, it would rotate faster than it does.
E. Astronomers’ interest in it ultimately led to a new theory of planetary formation.

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