Radio interferometry is a technique for studying details of celestial

All the other choices but E does give outside information irrelevant to argument such as "special care" (A), "signals" (B), "resolution" (C), "long time for development" (D).

hi
I dont know why I was tempted to go for D.....but I read the following earlier as well in this group


Inference questions repeat information that was given (usually information in the conclusion!).

So picked E

RI technique combines signals intercepted by widely spaced radio telescopes. RI technique requires 1) ultraprecise timing 2)exact knowledge of the locations of the telescopes 3) sophisticated computer programs. Hence successful implementation of RI technique was a significant technological accomplishment (We have been able to implement it).

A) Incorrect - Nowhere is it mentioned/suggested that the manner in which the satellite is launched influences the ability to calculate of it's orbit. Hence, special care is not required for calculation of it's orbit.

B) Incorrect - There is no mention/suggestion of strength of signal. Out of scope

C) Incorrect - There is no mention/suggestion of resolution. Out of scope

D) Incorrect - Computer programs were developed. They were sophisticated. But may not have taken time to develop. Even with extremely high complexity, a brilliant programmer could have done it in a day. There is no way to infer that it took time.

E) Correct - Fact1: RI has been successfully implemented + Fact 2: RI requires exact knowledge of the locations of the telescopes. Together they imply E) The location of an orbiting satellite relative to locations on Earth can be well enough known for interferometric purposes

VeritasKarishma - Can you please this question in more detail?

Thanks,
Anshul P

panshul22:

RI combines signals from various telescopes to study celestial objects.
It requires ultraprecise timing, exact knowledge of the locations of the telescopes, and sophisticated computer programs (It is a complicated technique)
Earth based telescope was successfully interferometrically linked with a satellite telescope.

Conclusion - This is a significant tech achievement.

We need to find what can be inferred i.e. as per the passage, what must be true. The correct option should give us no new information.

(A) Special care was taken in the launching of the satellite so that the calculations of its orbit would be facilitated.

We don't know whether special care was taken while launching to ease calculations or whether the computer programmer had to work extra hard to calculate its orbit while linking with terrestrial location.

(B) The signals received on the satellite are stronger than those received by a terrestrial telescope.

We don't know. Nothing says that signals on the satellite are stronger.

(C) The resolution of detail achieved by the satellite-Earth interferometer system is inferior to that achieved by exclusively terrestrial systems.

Again, we don't know.

(D) The computer programs required for making use of the signals received by the satellite required a long time for development.

Again, we don't know. They may have taken a short time but involved complex algorithms.

(E) The location of an orbiting satellite relative to locations on Earth can be well enough known for interferometric purposes.

Correct. We know that satellite telescope has been successfully interferometrically linked with terrestrial telescope. That means we could calculate location enough for our purpose (otherwise linking would not have been successful as per the highlighted portion above).

Answer (E)

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