After a five year journey from Earth, Juno – NASA’s solar-powered spacecraft safely entered Jupiter’s orbit early Tuesday. Juno was launched on 5 August 2011,from Cape Canaveral Air Force Station in Florida and the probe has travelled a total distance of 1,740 million miles (2,800 million kilometres) to reach the gaseous planet.
Juno’s main spacecraft body measures 11.5 feet (3.5 meters) tall and 11.5 feet in diameter. But with its three solar panels open, it spans about 66 feet (20 meters). Juno carries a suite of nine instruments to explore Jupiter from its interior to its atmosphere. Its colour camera dubbed JunoCam will take close-up photos of the poles and other points of interest. The three solar panels can generate 500 watts of electricity, enough to power its 29 sensors and nine instruments. Juno is an armoured spacecraft means its computer and electronics are locked in a titanium vault to shield them from harmful radiation. Juno’s infrared spectrometer and ultraviolet spectrograph will study the planet’s auroras in different wavelengths of light. A microwave sensor will use radio waves to search for water and ammonia hidden beneath the thick cloud-tops. A magnetometer, perched at the end of one solar-paneled arm, will create a 3D map of the planet’s enormous magnetic field, which should shed light on the internal dynamics that power it
Juno’s main aim is to understand the origin and evolution of Jupiter. Juno will investigate the existence of a solid planetary core, map Jupiter’s intense magnetic field, measure the amount of water and ammonia in the deep atmosphere, and observe the planet’s auroras.the important questions include: What’s at the core of Jupiter? What’s going on under Jupiter’s dense clouds? How much water exists? Why are Jupiter’s southern and northern lights the brightest in the solar system? How deep are those colourful bands and that mysterious giant red spot? We hope Juno will help to answer those questions by looking at Jupiter’s interior and give scientists a better idea of how the solar system formed 4.6 billion years ago.
Unusually for a robotic space mission, Juno is carrying passengers – three Lego figures depicting the Roman god Jupiter who drew a veil of cloud around himself to obscure his mischief, and his wife Juno, who was able to see through the clouds, are joined by a telescope-wielding Galileo Galilei, who discovered four of Jupiter’s moons. Pioneer in mission was Galileo, launched in 1989, circled Jupiter for 14 years and uncovered signs of an ocean beneath the icy surface of the moon Europa, considered a top target in the search for life outside Earth.
Juno is one of three New Frontiers probes that NASA is currently operating or building. The others are New Horizons which flew by Pluto in 2015, and OSIRIS-REx, which is expected to fly to asteroid 101955 Bennu in 2020 to collect a sample and return it to Earth. New Frontiers was a program NASA created in 2003 for medium-sized missions that are capped at $1 billion in development and launch costs each.
Juno made a discovery even before reaching its destination. As Juno entered in on Jupiter, its camera captured the massive planet appearing half-lit surrounded by its four main moons. NASA stitched the images together and created a time-lapse video showing the moons in action. There was a surprise: Jupiter’s second-largest moon, Callisto, appeared dimmer than scientists imagined. “We don’t know why,” said Bolton of the Southwest Research Institute in Texas.
As we know, Jupiter is the largest planet in our Solar System. The Earth could fit inside Jupiter more than 1000 times. Jupiter spins really fast; it turns on its axis once every 9 hours and 55 minutes. This rapid rotation flattens the planet slightly, giving it an oblate shape. Jupiter is made up of mainly hydrogen and helium the same basic ingredients as the sun.
Jupiter’s powerful winds are very different from those on Earth. They continually circle the planet, and have changed very little in the 300 years that scientists have studied them. Massive east-west winds in Jupiter’s equatorial region reach approximately 340 miles per hour ? twice as rapid as winds generated by strong hurricanes on Earth. At higher latitudes, the wind pattern switches to alternating jets that race around the planet.
Unlike Earth, Jupiter has no clear boundary between its atmosphere and the rest of the planet. All of the clouds and storms that we can see are located at the bottom of Jupiter’s troposphere, and they’re formed from ammonia, hydrogen sulfide and water. The top cloud layer contains ammonia ice. Below this are clouds made of ammonium hydrosulfide. Water clouds form down at the densest layer of clouds.
Jupiter’s Great Red Spot (GRS) is an atmospheric storm that has been raging in Jupiter’s southern Hemisphere for at least 400 years. Its similiar to a hurricane on Earth. The GRS rotates counter-clockwise and makes a full rotation every six Earth days. Winds at the very edges of the storm gust to 432 km/h, but inside the storm winds seem to be somewhat stagnant with no inflow nor outflow. The spot is large enough to engulf three Earths. Infrared data indicates that the GRS is colder and at a higher altitude than most of the other clouds on Jupiter. This red spot is also called “The Eye of Jupiter” because of its shape.
Jupiter Rings are faint and are only able to be viewed when Jupiter passes in front of the Sun. This is because the light from the Sun lights them up for us to see here on Earth. There are three rings in all. They are named Gossamer, Main and Halo. The ring system begins some 92,000 kilometres above Jupiter’s cloud tops and stretches out to more than 225,000 km from the planet. They are between 2,000 to 12,500 kilometres thick.
Jupiter has the strongest magnetic field of all the planets. Its radiation field is so powerful that it is the only planet in the solar system that actually emits more energy into space than it absorbs from the sun. Jupiter is a place too where liquid helium falls through the clouds like rain; where hydrogen is subjected to such pressures that it behaves like an electricity-conducting metal. Jupiter’s magnetic field is nearly 20,000 times as powerful as Earth’s, and the planet is surrounded by an intense radiation belt. This radiation amounts to 100 million X-rays in the course of a year, according to Heidi Becker, senior engineer on radiation effects at Nasa’s Jet Propulsion Laboratory.
Jupiter has 50 official moons and 12 provisional (unofficial) moons. The four largest and most well-known were discovered by Galileo in the year 1610. Their names are Io, Europa, Ganymede and Callisto. Europa is nearly the same size as Earth’s Moon and water-rich and has a warm interior so scientists think it could be hospitable to life.
Jupiter being the largest, most massive, fastest rotating, most hazardous planet of the solar system has the strongest magnetic field and the greatest number of known satellites . Radiation was a known obstacle. But perhaps the biggest potential risk of the Juno mission was less well-known: Jupiter’s rings. The Galileo mission in the 1990s made some observations of the rings of dust and debris that surround Jupiter, but NASA scientists still don’t know how close to the surface these get to the planet, nor do they know the distribution of material within them.Thus gas giant is still a mystery. That’s why NASA and so all we are so excited for sending JUNO a satellite into the planet’s orbit.
Juno will stay in orbit until February 2018, when NASA will purposefully crash the spacecraft into Jupiter. Juno is only the second mission designed to spend time at Jupiter. It’s the farthest solar-powered spacecraft from Earth and it’s one of the fastest spacecrafts ever made. It’s one small step into the future, for the future generations. I wish like goddess Juno, our JUNO could also peer through the clouds and reveal king of planets’ true nature.