Passage 33 : GMAT Verbal Section
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 18 Jan 2017, 15:18

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Passage 33

Author Message
Manager
Joined: 09 Jun 2005
Posts: 98
Location: New York
Followers: 1

Kudos [?]: 8 [0], given: 0

### Show Tags

05 Jan 2006, 13:18
passage 33
until recently most astronomers believed that the
space between the galaxies in our universe was a near-
perfect vacuum. this orthodox view of the universe is
now being challenged by astronomers who believe that a
(5) heavy "rain" of gas is falling into many galaxies from
the supposedly empty space around them. the gas
apparently condenses into a collection of small stars,
each a little larger than the planet jupiter. these stars
vastly outnumber the other stars in a given galaxy. the
(10) amount of "intergalactic rainfall" into some of these
galaxies has been enough to double their mass in the
time since they formed. scientists have begun to suspect
that this intergalactic gas is probably a mixture of gases
left over from the "big bang" when the galaxies were
(15) formed and gas was forced out of galaxies by supernova
explosions.
it is well known that when gas is cooled at a constant
pressure its volume decreases. thus, the physicist fabian
reasoned that as intergalactic gas cools, the cooler gas
(20) shrinks inward toward the center of the galaxy. mean-
while its place is taken by hotter intergalactic gas from
farther out on the edge of the galaxy, which cools as it is
compressed and flows into the galaxy. the net result is a
continuous flow of gas, starting as hot gases in inter-
(25) galactic space and ending as a drizzle of cool gas called a
"cooling flow," falling into the central galaxy.
a fairly heretical idea in the 1970's, the cooling-flow
theory gained support when fabian observed a cluster
of galaxies in the constellation perseus and found the
(30) central galaxy, ngc 1275, to be a strange-looking object
with irregular, thin strands of gas radiating from it.
according to previous speculation, these strands were
gases that had been blown out by an explosion in the
galaxy. fabian, however, disagreed. because the strands
(35) of gas radiating from ngc 1275 are visible in optical
photographs, fabian suggested that such strands consisted
not of gas blown out of the galaxy but of cooling flows
of gas streaming inward. he noted that the wavelengths
of the radiation emitted by a gas would changes as the
(40) gas cooled, so that as the gas flowed into the galaxy and
became cooler, it would emit not x-rays, but visible light,
like that which was captured in the photographs. fabian's
hypothesis was supported by canizares' determination in
1982 that most of the gas in the perseus cluster was at a
(45) temperature of 80 million degrees kelvin, whereas the
gas immediately surrounding ngc 1275 (the subject of
the photographs) was at one-tenth this temperature.

1. the primary purpose of the passage is to
(a) illustrate a hypothesis about the origin of galaxies
(b) provide evidence to dispute an accepted theory about the evolution of galaxies
(c) summarize the state of and prospects for research in intergalactic astronomy
(d) report new data on the origins of intergalactic gas
(e) reconcile opposing views on the formation of intergalactic gas

Arash
If you have any questions
New!
Manager
Joined: 13 Aug 2005
Posts: 136
Followers: 1

Kudos [?]: 1 [0], given: 0

### Show Tags

05 Jan 2006, 19:39
I think that the answer is D, but I might be wrong.
Here are my reasonings.
A - the passage does not talk about the origin of galaxies .
B- not about the evolution of galaxies
C - It's about intergalactic astronomy, but does not talk about prospects.
D - does not reconcile the opposing views.
Manager
Joined: 09 Jun 2005
Posts: 98
Location: New York
Followers: 1

Kudos [?]: 8 [0], given: 0

### Show Tags

05 Jan 2006, 19:45
that was exactly my reasoning...but that's not the OA
Senior Manager
Joined: 03 Nov 2005
Posts: 396
Location: Chicago, IL
Followers: 3

Kudos [?]: 50 [0], given: 17

### Show Tags

05 Jan 2006, 21:34
b) provide evidence to dispute an accepted theory about the evolution of galaxies

In order to answer primary purpose questions, it's necessary to understand the structure of the passage, the flow of an overall argument by identifying what role each paragrpah plays in the argument,

Here's the flow

1. In para 1, the conventional theory is introduced and, then, refuted because of newer, more sophisticated theory.
In para 2, scientific evidence to support this theory stated and evaluated.
_________________

Hard work is the main determinant of success

Director
Joined: 04 Oct 2005
Posts: 586
Location: Chicago
Followers: 1

Kudos [?]: 7 [0], given: 0

### Show Tags

05 Jan 2006, 23:10
I would go for B..
First Para first line : Till now, this was accepted theory but now astronomers r challenging it
2nd Para: Builds eveidence to support that the how the new theory works.
05 Jan 2006, 23:10
Similar topics Replies Last post
Similar
Topics:
Problem understanding passages 4 11 Sep 2016, 03:45
1 How to improve verbal from 33 14 10 Jul 2016, 00:37
6 HOW TO READ A PASSAGE 0 01 Jul 2015, 11:32
1 RC Passage and Question Difficulty 1 23 Jul 2014, 09:17
rc science passage 0 16 Jan 2008, 04:59
Display posts from previous: Sort by