What is the purpose of 'evolved Laser Interferometer Space "Antenna (eLISA)' project ?

Gives a concrete example (LIGO) of a laser interferometer being used to sense distortions in spacetime (gravitational waves).

A student can note that laser interferometers are used to detect gravitational waves and therefore would suspect eLISA (a laser interferometer in space) is aimed at gravitational waves rather than neutrinos.

Explains lasers as beams of light and gives practical context for laser use (optical phenomena), distinguishing laser photons from other particles.

A student can use this to recall that lasers detect/measure light-based effects, whereas neutrinos are different particles requiring different detector technology.

Describes the Cosmic Microwave Background as electromagnetic (microwave) radiation, illustrating that astrophysical observations distinguish between electromagnetic signals and other messengers.

A student can extend this rule: astronomy uses different instruments for different messengers (EM waves vs. neutrinos vs. gravitational waves), so instrument purpose follows the type of signal targeted.

Notes global trends in space programmes (space exploration and security) and that space missions attract specific technical investments.

A student can infer that specialized space missions usually have specific scientific goals (e.g., detecting a particular messenger), so one should check eLISA's stated target rather than assume neutrinos.

Mentions space probes and the Deep Space Network used to support interplanetary missions, showing that space missions use tailored ground/space infrastructure.

A student can use this pattern to reason that a space-based detector like eLISA would be paired with mission-specific support for its primary observable (e.g., interferometry for waves) rather than neutrino detection infrastructure.

Mentions LIGO (the Laser Interferometer Gravitational-Wave Observatory) physically sensed spacetime distortions from gravitational waves in 2015.

A student can note that LIGO's name and detection method link 'laser interferometer' technology to detecting gravitational waves and then compare that to eLISA's name to suspect a similar purpose.

Defines gravitational waves as spacetime ripples produced by massive accelerating objects (e.g., orbiting black holes) and describes their observable effects.

Using this, a student could infer that projects named with 'interferometer' aim to measure such tiny spacetime distortions caused by those sources.

UPSC question lists 'gravitational waves' as the significance of observed black hole mergers, linking such astronomical events to detection of gravitational waves.

A student could combine this example (merging black holes produce detectable gravitational waves) with knowledge that interferometers detect those signals to judge eLISA's likely goal.

States that gravitational waves are considered a piece of evidence for cosmological theories (Big Bang), indicating the scientific importance of detecting them.

A student might reason that a space mission named to include 'Laser Interferometer' would be designed to make such important gravitational-wave measurements from space.

Describes basic properties and safe use of lasers in an experimental context, linking lasers to precision measurement setups.

A student could generalize that laser-based interferometry (precision laser measurements) is an appropriate technology for sensing tiny spacetime distortions like gravitational waves.

Describes ground-based laser interferometer (LIGO) detecting gravitational waves from violent astrophysical events — establishes a pattern that interferometer projects study spacetime distortions/gravitational waves.

A student who knows eLISA is a space-based interferometer could extend this to infer eLISA's primary focus is likely gravitational-wave detection, not solar-flare communication effects.

Defines solar flares as magnetic storms with hot coronal eruptions — identifies the phenomenon (solar flares) whose effects on communications are in question.

Combine this with knowledge that solar flares produce energetic particles and radiation that can disrupt Earth-space communications to assess whether a mission studying flares would target such effects.

Explains that solar activity (coronal mass ejections) drives geomagnetic storms and affects the magnetosphere — connects solar eruptions to space weather that can impact systems near Earth.

Use a world-map or orbit facts to judge whether a space mission would be placed/ designed to monitor these near-Earth space-weather effects versus deep-space gravitational-wave measurements.

Notes that the ionosphere affects propagation of radio and microwave signals, implying solar/ionospheric variability can alter communications.

A student could combine this with the locations and altitudes at which a mission operates to evaluate whether that mission would be suited to study ionospheric/communication impacts.

States that satellite communication relays information from Earth and space — establishes why disruptions from solar activity matter for communications infrastructure.

With basic knowledge of what a satellite mission is designed to observe (communications vs. astrophysical signals), a student can judge whether eLISA's instrumentation would target communication disruptions or other phenomena.