New observations about the age of some globular clusters in our Milky

Prapon,

This seems wrong.
Answer choice E could, in no way , strengthen the conclusion. In fact its almost a direct rip off from a line in the passage.

IMO B

To address this question, our primary objective is to analyze what findings can help strengthen the conclusion the most.

The conclusion (revealed from the recent observations about globular clusters):-
Inside the same galaxy, there can be considerable variation in the ages of globular clusters. The conventional theory, which states that the "rapid" formation of the galaxy would mean stars in the halo should be nearly the same age, is NOT true.

Choice (B) A survey reveals that a galaxy close to the Milky Way galaxy contains globular clusters of ages close to the age of Palomar 12.
-- This survey can only reveal the age statistics of one edge of the age spectrum. i.e. as Palomar 12 is 5 billion years younger than most of the stars then, these stars are likely to be around the same age, hence will not help to the conclusion by studying the stars having wide spectrum of ages.

Choice (E) A study of over 1,500 individual stars in the halo of the Milky Way galaxy indicates wide discrepancies in their ages.
This study can provide statistics of the stars which have "wide" discrepancies in their ages, hence can help solidify the new observations that these stars can have considerable variation in ages. (phrase "wide" discrepancy in this context means "wide" variations).

HTH

1. The passage is primarily concerned with discussing
(A) the passage is about how the variation of age of globular clusters change view about the formation of galaxy... Anything less than the formation of galaxy is wrong...
(B) the passage is not about procedures takes... Anything less than formation of galaxy is wrong...
(C) there is no dispute... This is about a new discovery as opposed to what was conventionally thought about the formation of galaxy...
(D) CORRECT. this passage is about the theories on formation of galaxy.
(E) this totally miss the purpose of the passage... Out!




2. According to the passage, one way in which Larson's theory and the conventional theory of the formation of the Milky Way galaxy differ is in their assessment of the
(A) amount of time it took to form the galaxy.. Correct... If the Milky Way is composed of clusters then the age of its composition shows the age of Milky Way... Also it's time of for action.... I got this wrong but by Poe... It sticks out...
(B) size ... Definitely not the concern of these opposing theories..
(C) heck no! No discussion about types of gases...
(D) both theories base it on their believed age of clusters.. False...
(E) the passage discusses that the conventional theories believe that the stars are as old as the formation of the galaxy while the new theory shows that there is billions of years variation in age of starts or clusters... It is implied that the formation took longer...



3. Which of the following, if true, would be most useful in supporting the conclusions drawn from recent observations about globular clusters?
the recent theory is backed by data about variation in age of globular clusters... Hence, e


(E) A study of over 1,500 individual stars in the halo of the Milky Way galaxy indicates wide discrepancies in their ages.

4. If Bolte and his colleague are both correct, it can be inferred that the globular cluster Palomar 12 is approximately

(A) it is clear. The passage says 5 billion years younger than most and not all. False.
(B) false also. It is 5 billion yrs younger than most.
(C) correct. If the Palomar 12 is 5 billion years younger than most. Then there is one cluster 2 billion years older and another 2 billion yrs younger than most. Thenit follows that Palomar is 7 billion yrs older than another cluster.
(D) 12 billion years younger... Heck no!
(E) 5 billion younger than most and not 2 billion years. False again.


5. The passage suggests that Toomre's work complements Larson's theory because it
(A) no precise time frame discussed in the passage
(B) no subtle alteration by Toomre's work...
(C) the support given was through a computer model not astronomical ...
(D) provides theoretical support for the ideas suggested by Larson ... correct.
(E) no applicability discussed



6. Which of the following most accurately states a finding of Bolte's research, as described in the passage?

(B) The ages of at least some globular clusters in the Milky Way galaxy differ by at least 4 billion years.

I did not go through all the answers but B is obviously correct. There are some 2 billion years older than most or 2 billion yrs younger than most. Thus, gap is 4 billion years. At least some is safe wording.


7. The author of the passage puts the word "renegade" (line 29) in quotation marks most probably in order to

Renegade to me I thought since they find some findings against conventional theory. They look to renegade theory. Perhaps, what once thought wrong old be actually right.

(E) indicate that the theories in question are no longer as unconventional as they once seemed

Got all 7 right in under 12 minutes.
Very interesting content!!
Good read..

Regards,
Chechaxo

two wrongs 5 and 6.
5- should have gone back and read the lines once again, clearly states the answer option.
6- still confused .. how does it provide theoretical support?? but by POE only that answer sticks out!!
read the passage in 3.40 min and completed in 11.50 min

Hi,

Can someone please explain the relevance of the word 'renegade' in question 7?

Thanks,

v2rfrendz

Posted from my mobile device

The author is saying the conventional theory is actually not as conventional as thought to be. We need to revisit the theory and find out whether it is actually true keeping in mind the new research that has been done.

I agree with your answer and explanation provided to question no 6 but i wanna know on what basis do I eliminate "option c" of question 6. The findings stated in question stem is exactly similar to that stated in the passage so i prefer option c over option b.

why the answer is not C for Question no 6?

I got Q5 wrong. I chose E as my answer. Somebody please help. The computer models suggest that the ideas of the scientist also apply to spiral galaxies not just within a galaxy. This clearly means that there is a wider applicability. I don't disagree with the OA but I was confused between the two and got this wrong. Is my approach wrong here? Does "wide applicability" need to be explicitly stated in the passage for E to be correct? what did I do wrong?

[box_out][box_in]1. The passage is primarily concerned with discussing

(A) the importance of determining the age of globular clusters in assessing when the Milky Way galaxy was formed -Incorrect. The passage is discussing various theories
(B) recent changes in the procedures used by astronomers to study the formation of the Milky Way galaxy -Incorrect
(C) current disputes among astronomers regarding the size and form of the Milky Way galaxy -No disputes have been discussed
(D) the effect of new discoveries regarding globular clusters on theories about the formation of the Milky Way galaxy -Correct. Various theories have been discussed and their effects on others have been pointed out.
(E) the origin, nature, and significance of groups of stars known as globular clusters -Incorrect

2. According to the passage, one way in which Larson's theory and the conventional theory of the formation of the Milky Way galaxy differ is in their assessment of the

(A) amount of time it took to form the galaxy -Correct. Conventional theory states that the galaxy was formed in short time while the other one states that the galaxy was formed in billions of years
(B) size of the galaxy immediately after its formation -irrelevent
(C) the particular gases involved in the formation the galaxy -irrelevant
(D) importance of the age of globular clusters in determining how the galaxy was formed -Out of scope
(E) shape of the halo that formed around the galaxy -Irrelevant

3. Which of the following, if true, would be most useful in supporting the conclusions drawn from recent observations about globular clusters?

(A) There is firm evidence that the absolute age of the Milky Way galaxy is between 10 and 17 billion years. -This is an exaggerated choice
(B) A survey reveals that a galaxy close to the Milky Way galaxy contains globular clusters of ages close to the age of Palomar 12. -Other galaxy? Incorrect
(C) A mathematical model proves that small gas clouds move in regular patterns. -Model doesn't talk about regular patterns
(D) Space probes indicate that the stars in the Milky Way galaxy are composed of several different types of gas. -types of gases? incorrect
(E) A study of over 1,500 individual stars in the halo of the Milky Way galaxy indicates wide discrepancies in their ages. -Correct.

4. If Bolte and his colleague are both correct, it can be inferred that the globular cluster Palomar 12 is approximately

(A) 5 billion years younger than any other cluster in the galaxy -any? exaggerated
(B) the same age as most other clusters in the galaxy -same age? out of scope
(C) 7 billion years younger than another cluster in the galaxy -Correct. (5+2)
(D) 12 billion years younger than most other clusters in the galaxy -12? Incorrect
(E) 2 billion years younger than most other clusters in the galaxy -Not 2 but 5

5. The passage suggests that Toomre's work complements Larson's theory because it

(A) specifies more precisely the time frame proposed by Larson -time?
(B) subtly alters Larson's theory to make it more plausible -alters?
(C) supplements Larson's hypothesis with direct astronomical observations -astronomical observations?
(D) provides theoretical support for the ideas suggested by Larson -Correct.
(E) expands Larson's theory to make it more widely applicable -expand?

6. Which of the following most accurately states a finding of Bolte's research, as described in the passage?

(A) The globular clusters in the Milky Way galaxy are 2 billion years older than predicted by the conventional theory. -incorrect
(B) The ages of at least some globular clusters in the Milky Way galaxy differ by at least 4 billion years. -correct. (2+2)
(C) One of the globular clusters in the Milky Way galaxy is 5 billion years younger than most others. -Incorrect. This was Bolte's college's observation
(D) The globular clusters in the Milky Way galaxy are significantly older than the individual stars in the halo. -out of scope
(E) Most globular clusters in the Milky Way galaxy are between 11 and 15 billion years old. -exaggerated

7. The author of the passage puts the word "renegade" (line 29) in quotation marks most probably in order to
--I didn't know the meaning of "renegade" but solved it using the context of the passage.
(A) emphasize the lack of support for the theories in question -A mathematical model supports a theory. Incorrect
(B) contrast the controversial quality of the theories in question with the respectable character of their formulators -Character of the inventors is not discussed. Incorrect
(C) generate skepticism about the theories in question -The passage is not generating any skepticism regarding the theories.
(D) ridicule the scientists who once doubted the theories in question -The last para is definitely not ridiculing anyone
(E) indicate that the theories in question are no longer as unconventional as they once seemed -Correct. Only remaining choice, that also makes sense as per the passage

Question 3

The conclusion drawn from recent observations about globular clusters is that The Milky Way may have formed from the collapse of many clusters into a single galaxy, over a long period of time. Here's how this conclusion is presented in the structure of the passage:

• P1: The Milky Way is formed of many (~125) globular clusters distributed in a halo around the galactic nucleus. This distribution holds vital clues to how the galaxy was formed.
• P2: Conventional theory says: The Milky Way was formed in a short period of time (~200 million years), from the collapse of a single spherical cloud of gas. This implies that all stars in the halo should be nearly the same age.
• P3: Bolte has found discrepancies in the age of stars as large at 2 billion years. His findings challenge the conventional theory.
• P4: Larsons' "renegade" theory explains these discrepancies by arguing that the Milky Way was actually formed from multiple gas clouds. Toomre's models support this theory by suggesting how multiple galaxies could merge into one.

The best answer choice will back up these recent observations of age discrepancies within the galactic halo (wow, I am so glad I got to say "galactic halo") or reinforce the "renegade" theory by explaining how multiple galaxies could become one.


Why do we care about the absolute age of the Milky Way as a whole? We're looking for information about the age of stars in the halo. This is irrelevant to the question being asked, so we we'll eliminate (A).


We're only concerned about explaining age discrepancies within the Milky Way galaxy. Knowing the age of clusters in another galaxy altogether (especially if this knowledge doesn't tell us anything about how they fit into the bigger picture for that galaxy) won't help us strengthen or weaken the conclusion we care about, so let's eliminate (B).


Without more information about how these regular patterns result (or don't result) in collisions and the loss of orbital energy, we can't tie this model back to the theory of many galaxies becoming one Milky Way. Let's eliminate (C).


As with choice (C), knowing that there are different types of gas doesn't help us bridge the logical gap between many galaxies existing and many galaxies merging. Eliminate (D).


This choice explicitly reinforces the conclusion by telling us that many individual stars in the halo of the Milky Way have wide discrepancies in age. If true, we've just taken the example of Palomar and multiplied by it by 1,500. This adds a great amount of quantitative support to Bolte's recent findings. It directly attacks the conventional theory by showing exactly how much variance we're seeing in the age of stars in this halo. It's by far the best answer choice, so we'll stick with (E) and move on.

Question 5

In the final paragraph, the author presents "renegade" theories that could explain the large age discrepancies between globular clusters. Larson's theory is that hundreds of small gas clouds, rather than a single gas cloud, formed what we observe today as one galaxy: the Milky Way. Toomre's computer modeling suggests that multiple spiral galaxies could indeed merge into a single galaxy. Larson's work and Toomre's work reinforce each other, because both illustrate the same theoretical statement: Multiple galaxies can become one, over time.


Now that we've clarified the purpose of this paragraph, let's take a closer look at these two choices.


As you know, (D) most closely captures what we've just read. Toomre's models suggest that multiple galaxies could lose enough energy to merge into one. This provides support for the Larson's big-picture theory (multiple gas clouds becoming one system) as well as the specific process at the heart of that theory (losing orbital energy).


The key words here aren't only "widely applicable." We also have to decide whether Toomre's work is really expanding Larson's theory, because we're being asked how Toomre's work is complementing Larson's. We should eliminate (E) if either of these phrases aren't supported by the passage.

Let's recall why the author brought up Larson and Toomre in the first place: Both works suggest that many galaxies (whether worded as "hundreds of small gas clouds" or "closely interacting spiral galaxies") could become one. So the point of modeling spiral galaxies isn't to look at one galaxy and apply observations about it to many different kinds. The point is to illustrate how these multiple galaxies could have merged into a single galaxy.

Toomre's modeling shows how orbital energy plays a role in this merge, but it does not expand the theory of "many become one"...nor does it show us other ways that theory can be applied (for instance, to things that aren't galaxies at all). That's why we eliminate (E). It's more about matching the author's reason for bringing up another person's work than it is about matching specific keywords from choice to passage.

I hope this helps you... um, feel like you're surrounded by a galactic halo...?

Got Q2, 3, and 6 Incorrect.

Writing for clarity and understanding.

Passage map:
P1: to state that new info has emerged regarding a conventional theory on milk way
p2: to state the conventional theory and question what it failed to account for - age
p3: to describe what led to this questioning - observation regarding different ages
p4: to state another theory potentially explaining this new observation (age)

One way in which Larson's theory and the conventional theory differ is in their assessment of:

Now I got this wrong because I misread the question. Specifically, I read up to "DIFFER" and left off "in their assessment of..."

The only comparable thing assessed by the two theories is the formation of the Milky Way:
conventional theory: Milky Way formed over ~200m
Larson's theory: Milky Way formed over a period of ~1.0bn years

This is the clear difference making A the answer.

B- incorrect as nothing is mentioned with respect to the size of the galaxy
C - nothing is mentioned of the types of gasses, just that gases were present
D - reasons above. I incorrectly D, not reading the "in their assessment of". The conventional theory FAILS TO ACCOUNT FOR age.
E - nothing is mentioned with respect to the shape of the halo

Question 3
Which of the following would support the conclusions drawn from recent observations?
The conclusion is that ages of global clusters differ in the formation of the galaxy.
A is incorrect as its unclear how the age of the galaxy as a whole can strengthen the recent observations that deal with specific age variations
B is incorrect as it is really hard to see how galaxies closer to the age of P12 would support recent observations. The recent observations are more so Larson's "radical" theories anyway.
C is incorrect but I chose this because I thought that evidence of the gas trajectory would help Larson's argument in that if we could predict the trajectory of the gas cloud we could trace its formation back through its travel path, but i realise this is a step way too far, so its fairly hard to tie this back to the theory
D the composition of gas is irrelevant to the recent observations, which don't quote composition as a factor whatsoever
E is justifiably correct since a wider sample base supports the conclusion more since Bolt's evidence is vague in that it doesn't refer to any sample size and in fact Bolt makes specific reference to outlier stars (5 bn years younger etc.) so a wider sample set would serve well.


Question 6
I stupidly chose (C), which is a finding of Boltés colleague, not Bolt himself (As pointed out by charles)
Yes, B is understandably correct because some clusters are 2bn older than X, some are 2bn younger than X, thus the gap of 4bn stands to reason that the age of some differ by 4bn.
A - incorrect because conventional theory never took into account age
D- incorrect because such information is never provided for us to determine this
E - incorrect because Bolt never mentions anything about the age of the milky way. The conventional theory and radical theories do.

Hi GMATNinja VeritasKarishma AndrewN AjiteshArun

I chose C confidentially , I rejected E strongly
( later found E to be correct, now in shock)

Please help me to clarify my doubts:

Conventional theory says: Such a rapid formation of the galaxy would mean that all stars in the halo should be very nearly the same age.

globular clusters ( group) of stars.
P3- Recent observations: refers about age of clusters; not individual age of stars in clusters..

Kindly see my reasoning for E and C:

Here wide discrepancy means age of individual stars was found to be different in different theories /experiments.
1: How does discrepancy in results support the age variation about global clusters? If discrepancy, then we don't trust such finding. Should not the correct option say : age of global clusters is found to be wide varied . It adds weight to claim that there is wide variation in age of clusters.

2: If age of all stars in cluster is same then it is easy to determine the age of cluster ( it would be same as age of all stars as the number is same) . But if age of different stars in clusters is different then how can I determine the age of this cluster. I wanted to look for an option that talks about clusters or clusters age not individual stars.

3: If age of different stars are different, I can’t assume how to group them into various clusters age group . it means particular age group keep in particular cluster and it is also possible that all clusters have stars of similar ages. In any way, I not able to reach to conclusion of determining that age of different clusters is not same.

4: GMATNinja: If true, we've just taken the example of Palomar and multiplied by it by 1,500. ( Refer)
I don't understand this line.

With so many strong points to reject E, When I read option C, i felt confident for C.



Yes it is not directly help to determine about age of clusters but as per statement:



Atleast it adds some weight indirectly to determine the conclusion that once small gas clouds move in regular patterns then it could merge into single galaxy and by interactions of these clouds the clusters can be formed and hence different gas clouds merge at different times then cluster age could be different accordingly.

Please suggest.
GMATNinja VeritasKarishma AndrewN AjiteshArun

Sorry, but I agree with eaakbari. The fact that there is a study showing that clusters have different ages seems sufficient, explaining that individual stars also have discrepancies in ages is just an overkill. Answer B may not be great, but at least makes you think that maybe the two galaxies clusters are related.

In question 6:

The passage contends that the scientist found only one of each type of clusters: one which is 2 million years younger and one which is 2 million years older.

In B we have the word "some". My question is how can we be sure that there are other clusters which are exactly 2 million years younger or older. What if all the others are between this interval? What do I miss?