It’s NASA’s most powerful space observatory, launched on December 25, 2021. Built in collaboration with ESA (European Space Agency) and CSA (Canadian Space Agency), JWST is often called the successor to Hubble, but it goes much further:
Infrared Vision: Unlike Hubble, which mainly sees in visible and ultraviolet light, JWST observes primarily in the infrared spectrum. This lets it peer through cosmic dust and study the earliest galaxies, stars, and planetary systems.
Mirror: Its segmented gold-coated mirror is 6.5 meters wide, over 2.5x bigger than Hubble’s.
Orbit: It sits at the Lagrange Point 2 (L2), about 1.5 million km from Earth, shielded by a massive five-layer sunshield that keeps its instruments ultra-cold.
Science Goals:
Studying the first stars and galaxies after the Big Bang.
Understanding the evolution of galaxies.
Investigating star and planet formation.
Searching for atmospheres and signs of habitability on exoplanets.
Since starting its science mission in July 2022, JWST has already:
Found some of the earliest galaxies ever observed, from just 300–400 million years after the Big Bang.
Provided detailed spectra of exoplanet atmospheres (like WASP-39b, where it detected carbon dioxide).
Captured breathtaking images of nebulae, galaxy clusters, and star nurseries with unprecedented clarity.
Great question! 🚀
The oldest object sent to space by any country that is still working is Voyager 1, launched by NASA on September 5, 1977.
Why Voyager 1 is special:
It is the most distant human-made object, currently over 24 billion km (about 160 AU) away from Earth.
In 2012, it became the first spacecraft to enter interstellar space.
It is still in contact with NASA’s Deep Space Network, sending back data about cosmic rays, magnetic fields, and interstellar plasma.
Voyager 1 carries the Golden Record, a message from Earth with sounds, images, and greetings in multiple languages for any possible extraterrestrial civilization.
Other long-lived spacecraft:
Voyager 2 (launched August 20, 1977) – still working, exploring interstellar space.
Pioneer 10 & 11 (1972–1973 launches) – first to cross the asteroid belt and reach outer planets, but lost contact (last signals received in 2003 and 1995).
Hubble Space Telescope (1990) – still active and producing science alongside JWST.
OSO-7 solar observatory (launched 1971 by NASA) and some Soviet satellites still orbit Earth as inactive debris, but not functioning.
✅ So, the oldest functioning spacecraft is Voyager 1 (almost 48 years old in 2025), still talking to us across interstellar space.
The spacecraft that has travelled the farthest and is still working (sending data) is Voyager 1.
Here are the latest verified details:
🚀 Key Facts About Voyager 1
Launch date: September 5, 1977.
Left the heliosphere (entered interstellar space): August 2012.
Distance from Earth: Over 15 billion miles (≈ 24 billion km).
Data transmission: As of mid-2024, Voyager 1 is sending back usable scientific data from all four of its working science instruments.
Here are some of the spacecraft that have travelled very far and are still sending data (or were very recently), besides Voyager 1. I list their approximate current status and how far they are, to the extent known.
🚀 Other Very-Distant Spacecraft Still Working
Spacecraft Launched Status / what it’s doing now Approximate Distance & Notes
Voyager 2 1977 Still operating, though with fewer science instruments active (some being shut off to conserve power). Over 13 billion miles (~21 billion km) from Earth.
New Horizons 2006 Still healthy, operating in the Kuiper Belt / beyond, doing heliophysics / other science. It’s far, but less distant than Voyagers. It’s thousands of millions of miles from Earth, but still well inside the outer regions of the Solar System.
✋ Not Still Working (but used to be farthest etc.)
Pioneer 10 & Pioneer 11: These were very distant and carried plaques etc., but they are no longer sending scientific data. Pioneer 10’s mission formally ended (no more science instruments sending data) in 1997.
Others (older missions) have ceased operations or are out of power or contact.
✅ Comparison: Who’s the “Longest-Traveled & Still Working”
From current available info:
Voyager 1 is the most distant object still sending usable data.
Voyager 2 is the second — also in interstellar space, still sending data, though gradually losing instruments/power.
New Horizons is also working, though it's much closer than the Voyagers.
Great that you asked about Aditya-L1 ☀️ — India’s first dedicated solar observatory, launched by ISRO on September 2, 2023.
Here’s where it stands compared to Voyagers and New Horizons:
🔭 Aditya-L1 Mission
Destination: The L1 Lagrange point, about 1.5 million km from Earth in the direction of the Sun.
Arrival: Successfully placed in halo orbit around L1 on January 6, 2024.
Purpose: Continuous observation of the Sun, without the interference of Earth’s atmosphere or eclipses.
Instruments (7 payloads):
Visible Emission Line Coronagraph (VELC) – studies the solar corona.
Solar Ultraviolet Imaging Telescope (SUIT) – observes the photosphere and chromosphere.
Plasma Analyser Package for Aditya (PAPA) – studies solar wind.
Solar Low Energy X-ray Spectrometer (SoLEXS), High Energy L1 Orbiting X-ray Spectrometer (HEL1OS), etc.
🌍 Distance Traveled
Aditya-L1 is much closer to Earth compared to the Voyagers (1.5 million km vs. 24 billion km).
But its focus is different: rather than long-distance exploration, it provides continuous, real-time solar monitoring, crucial for space weather forecasts and protecting satellites, power grids, and communication systems on Earth.
📡 Current Status (2025)
Aditya-L1 is fully operational and transmitting scientific data.
ISRO has already released the first solar images from SUIT and VELC, showing the Sun’s atmosphere and flares in unprecedented detail for India.
It’s expected to operate for at least 5 years, possibly longer.
👉 So in short:
Voyager 1 & 2 = farthest, oldest, still working.
New Horizons = active, but not as far.
Aditya-L1 = not the farthest, but a unique mission dedicated to studying the Sun, sitting at a perfect balance point (L1) to watch solar activity 24/7.
Excellent! Let’s compare Aditya-L1 (India, ISRO) and the Parker Solar Probe (USA, NASA).
Both are solar missions, but their design, distance, and science goals are very different — almost complementary.
🔭 Aditya-L1 vs. Parker Solar Probe
Feature Aditya-L1 (ISRO, 2023) Parker Solar Probe (NASA, 2018)
Mission Type Space-based solar observatory at Lagrange point L1. In-situ probe flying into the Sun’s outer corona.
Orbit / Location Halo orbit around L1 (1.5 million km from Earth), constant view of the Sun. Highly elliptical orbit, passes as close as 6.16 million km from the Sun’s surface (closest ever).
Main Focus Remote sensing & monitoring: corona, chromosphere, solar wind, flares, CMEs, space weather. In-situ measurements: directly samples plasma, magnetic fields, and particles in the Sun’s atmosphere.
Instruments 7 payloads: VELC (coronagraph), SUIT (UV telescope), PAPA (plasma analyzer), SoLEXS, HEL1OS, etc. 4 main instruments: FIELDS (electric & magnetic fields), WISPR (white-light imager), SWEAP (solar wind plasma), ISʘIS (energetic particles).
Data Type Images + spectra + long-duration monitoring. Direct particle, plasma & magnetic field data + images from near-Sun environment.
Distance from Earth ~1.5 million km (0.01 AU). Ranges 0.25 AU → 0.046 AU (6.16 million km from Sun at perihelion).
Scientific Goal Predict solar storms, understand heating of corona, improve space weather forecasts for Earth. Reveal why corona is so hot, how solar wind accelerates, and study energetic particle origins.
Expected Lifetime 5+ years (depends on payload health). ~7 years (till ~2025/26) – already completed 19 close perihelion passes by 2024.
🌞 Complementary Roles
Aditya-L1 = the Sun’s watchtower: Continuous, wide-angle remote observation. Helps monitor events like solar flares and CMEs before they reach Earth.
Parker Probe = the Sun’s explorer: Gets inside the solar corona, feeling the Sun’s plasma and magnetic storms directly, something no other spacecraft has done.
Together, they give a complete picture:
Aditya-L1 → sees what happens on the Sun.
Parker Probe → measures how it feels up close.
💡 Think of it this way:
Aditya-L1 is like a doctor monitoring a patient with scans and instruments from outside, while
Parker Probe is like a micro-camera going inside the bloodstream to see how things actually flow.
Excellent technical question 🌞 — because both Aditya-L1 and Parker Solar Probe face extreme conditions near the Sun, their instruments are built with highly specialized materials.
🔭 Aditya-L1 (ISRO, 2023)
At the L1 point (1.5 million km from Earth), Aditya-L1 does not go dangerously close to the Sun like Parker. The thermal challenge is moderate — constant solar radiation, but manageable with existing satellite-grade materials.
🛠️ Materials & Design for Aditya-L1
Multi-Layer Insulation (MLI) → aluminized Mylar or Kapton sheets, to reflect solar radiation and insulate instruments.
Aluminum & Titanium Alloys → main spacecraft structure, lightweight and strong.
Solar Filters (for VELC & SUIT) → special optical coatings (aluminum, magnesium fluoride, etc.) to block excess sunlight and only allow useful wavelengths.
Radiators & Thermal Coatings → white paints, ceramics, and second-surface mirrors to reject heat.
Radiation-hardened electronics → protected against solar particle storms.
👉 In short: Aditya-L1 uses well-tested space-grade insulation and reflective materials, as the heat load at L1 is not beyond standard spacecraft capability.
☀️ Parker Solar Probe (NASA, 2018)
Parker is the closest spacecraft to the Sun in history — only 6.16 million km from the surface, where temperatures reach ~1370°C (2500°F). This required revolutionary materials.
🛠️ Materials & Design for Parker Solar Probe
Thermal Protection System (TPS) → an 11.43 cm thick carbon-carbon composite shield, covered in ceramic white paint to reflect sunlight.
Core: carbon foam (97% air, very light, excellent insulator).
Facesheets: carbon-carbon composite for high strength at extreme heat.
Solar Arrays with Cooling → arrays are water-cooled with deionized water flowing through titanium pipes to keep them below 160°C.
Heat-resistant Sensors → tungsten, molybdenum, sapphire windows to withstand plasma and radiation.
High-temperature adhesives & ceramics to hold components stable under repeated heating cycles.
👉 Parker’s heat shield allows the spacecraft body to remain at room temperature (~30°C) even while the outside shield faces 1370°C!
⚖️ Comparison
Aditya-L1 → Handles normal solar heating at L1 with standard insulation, coatings, and space alloys.
Parker Solar Probe → Faces the most extreme environment ever attempted, requiring next-generation carbon composites, water-cooled systems, and advanced ceramics.
✅ In essence:
Aditya-L1 = observer at safe distance → durable but conventional materials.
Parker Probe = adventurer near the Sun → cutting-edge heat shield technology never used before.
Got it ✅ Let me give you a detailed, yet clear narrative about the James Webb Space Telescope (JWST) and Voyager 1 — two of humanity’s greatest space missions, but with very different purposes.
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🌌 James Webb Space Telescope (JWST)
Launch: December 25, 2021 (NASA + ESA + CSA).
Location: Orbits around the Sun–Earth L2 point (1.5 million km from Earth).
Mirror: 6.5 m gold-coated beryllium mirror (largest ever in space).
Specialty: Works mainly in the infrared spectrum, unlike Hubble (which focused on visible and ultraviolet).
🔭 Mission Goals
1. Look back in time to find the first galaxies after the Big Bang.
2. Study how galaxies evolve over billions of years.
3. Observe star and planet formation inside dusty nebulae.
4. Analyze exoplanet atmospheres for possible signs of habitability.
🛠️ Science Achievements (so far)
Detected galaxies just 300–400 million years after the Big Bang.
Measured atmospheres of exoplanets (e.g., found CO₂ on WASP-39b).
Produced stunning infrared images of nebulae, galaxy clusters, and star nurseries with detail unseen before.
👉 JWST is like a time machine: it looks billions of years into the past by detecting faint infrared light stretched by cosmic expansion.
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🚀 Voyager 1
Launch: September 5, 1977 (NASA).
Original Mission: Flybys of Jupiter and Saturn (part of the Grand Tour).
Extended Mission: Explore the outer solar system and now interstellar space.
🌍 Distance & Record
Farthest human-made object: ~24 billion km (15 billion miles) from Earth (2025).
Entered interstellar space in 2012 — the first spacecraft to do so.
🔭 Mission Goals Now
Measure cosmic rays, magnetic fields, and plasma density in interstellar space.
Send back data via the Deep Space Network (signal takes ~22 hours one way).
🛠️ Special Features
Powered by radioisotope thermoelectric generators (RTGs), still producing limited power after almost 48 years.
Carries the Golden Record, with sounds, images, and greetings from Earth — a message to any possible extraterrestrials.
👉 Voyager 1 is like a message in a bottle drifting into the cosmic ocean, carrying human curiosity beyond the Sun’s influence.
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⚖️ Comparison
JWST: A cutting-edge telescope looking inward toward the ancient universe with unmatched detail.
Voyager 1: A pioneer spacecraft moving outward into interstellar space, showing how far human technology can travel.
Together, they represent the two directions of exploration:
JWST looks back in time, asking “Where did we come from?”.
Voyager 1 moves forward into space, asking “Where are we going?”.