What are the approximate ages of UBC 63A and UBC 63B?
- A.21 million years and 562 million years
- B.562 million years and 21 million years
- C.100 million years and 400 million years
- D.6 million years and 26 million years
Correct answer
Explanation
The correct answer is 21 million years and 562 million years. UBC 63A is the young cluster of the pair at roughly twenty-one million years, while UBC 63B is much older at about five hundred sixty-two million years. This substantial difference in age is the main evidence that the two systems did not begin as a single cluster and only came to lie near each other later. Option B reverses the labels, giving the older age to the younger cluster, which is a common trap. Option C offers ages that appear nowhere in the study. Option D confuses ages with two other figures from the work, the six million years since the clusters made their closest approach and the present separation of about twenty-six parsecs. Candidates should fix the pairing firmly in mind, so option A is correct.
Read the full article: Indian Astronomers Find Star Cluster UBC 63 Is Really Two
Practice Questions
What did a team led by Indian astronomers find about the galactic open cluster UBC 63?
- A.It is the nearest open cluster to the Sun
- B.It is actually two distinct clusters that passed close to each other
- C.It hosts the first planet found outside the Milky Way
- D.It is merging with the Andromeda galaxy
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The group, which lies about 4892 light years away and had been treated in the limited earlier literature as a single cluster, was found to hold two separate stellar populations, now named UBC 63A and UBC 63B. Their brightness and colours formed two sequences in the colour magnitude diagram, and…
Read the full explanation →Data from which space mission enabled the discovery that UBC 63 is a double cluster system?
- A.Hubble Space Telescope of NASA
- B.Gaia mission of the European Space Agency
- C.AstroSat of ISRO
- D.James Webb Space Telescope
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The researchers used Gaia measurements, which give exceptionally precise positions and motions for stars right across the Milky Way, and it was these data that revealed two populations of starkly different ages inside what had been taken for one cluster.
Read the full explanation →What authorisation fee has TRAI recommended for Satellite Communication Network provider authorised entities?
- A.3 per cent of Adjusted Gross Revenue
- B.5 per cent of Adjusted Gross Revenue
- C.8 per cent of Adjusted Gross Revenue
- D.12 per cent of Adjusted Gross Revenue
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TRAI has recommended that the authorisation fee for a Satellite Communication Network provider authorised entity be eight per cent of its adjusted gross revenue, and that no minimum authorisation fee be imposed on it.
Read the full explanation →What is the maximum duration recommended for the Satellite Communication Network Provider Authorisation?
- A.5 years
- B.10 years
- C.20 years
- D.30 years
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TRAI has recommended that the Satellite Communication Network Provider Authorisation be granted for the national area with a maximum duration of twenty years, and that it carry a provision for renewal for up to a further twenty years.
Read the full explanation →Under which section of the Telecommunications Act, 2023 has TRAI recommended creating the Satellite Communication Network Provider Authorisation?
- A.Section 2(1)(a)
- B.Section 3(1)(b)
- C.Section 4(4)
- D.Section 10(2)
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The Department of Telecommunications had told the regulator that it proposed to bring in a Satellite Communication Network authorisation under Section 3(1)(b) of the Telecommunications Act, 2023, and asked TRAI for the terms and conditions, including spectrum assignment for feeder and user links.
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