According to a recent newspaper report, an international team of astronomers studying nearly 446,000 galaxies via the Hubble Space Telescope has confirmed that the expansion of the universe is accelerating. By utilising a technique known as "weak gravitational lensing" to observe how light is distorted by dark matter, researchers mapped the distribution of matter and the history of cosmic expansion, determining that an unknown force called "dark energy" has been driving this acceleration for the past two billion years. This study, which involved 1,000 hours of observation and 600 Earth orbits by the Hubble telescope, marks the first time such measurements were successfully conducted using gravitational lensing alone, and it further reinforces the existence of an invisible web of dark matter that constitutes 80% of the universe. Which of the following BEST summarises the main idea of the text above?
Step-by-step Solution:
A good summary captures the core findings and key methods of the passage without getting bogged down exclusively in trivial details or misrepresenting the facts. Let's evaluate the options: Option A focuses too heavily on the metrics of the study (hours, orbits, galaxy count) while entirely omitting the actual scientific discovery (universe expansion and dark energy). Option B is factually inaccurate according to the text. The passage states this reinforces existing knowledge, not that they noticed dark matter for the 'first time'. Option C incorrectly claims that the main point of the passage is proving 'weak gravitational lensing' is the 'best technique', which misses the central cosmic discovery. Option D accurately captures the primary scientific conclusion (dark energy accelerates universe expansion) alongside the source/methodology (Hubble telescope, weak gravitational lensing). This is the most comprehensive and accurate summary.