Posts tagged solar system.
Postcards from Mars
The rings ofhave puzzled astronomers since Galileo Galilei discovered them with his telescope in 1610.
They’re incredibly thin. The main rings are generally only about 30 feet (10 meters) thick, though parts of the main and other rings can be several kilometers thick. The rings are made of dusty ice, in the form of boulder-sized and smaller chunks that gently collide with each other as they orbit around Saturn. Saturn’s gravitational field constantly disrupts these ice chunks, keeping them spread out and preventing them from combining to form a moon.
(Video credit: NASA)
10 Things we want to know about Jupiter
Jupiter, the largest planet of our solar system is the fifth planet after the Sun, and lies between the planets, Mars and Saturn. It is also the fourth brightest object in the sky after the Sun, Moon and Venus and is also called the ‘ruler of the night skies’. It is the first gaseous planet (Saturn, Uranus and Neptune being the other gas planets) to be discovered in our solar system and radiates twice as much as heat than it absorbs from the sun.
1. When was Jupiter discovered and how did it get its name?
There is no information regarding who were the first people to discover this large planet. Jupiter is a planet that is visible to the naked eye and is usually the brightest star appearing in the night sky. Which means anyone and everyone can see it. Then who gave Jupiter its name? It’s known that the Romans were the ones who named this large planet, Jupiter after the king of Roman Gods- ‘Jupiter’. Jupiter happened to be the Roman name of the supreme Greek God, Zeus. Since Jupiter appeared big and bright in the sky, they named it after their God. Interestingly, most of the moons of Jupiter are named after the daughters of Jupiter.
2. How do we know all that we know about Jupiter?
It was Galileo Galilei in 1610, who through his telescope found that Jupiter had four moons orbiting it. Further, in 1660, Cassini came across bands and spots on Jupiter’s surface and as a result was able to calculate the planet’s period of rotation. However, the first spacecraft to visit and explore Jupiter was Pioneer 10, in 1973.
Pioneer 11(1974), Voyager 1 & 2 (1979) and Ulysses (1992) followed Pioneer 10’s lead and have to be given due credit for bringing to us all these interesting facts about Jupiter. In 1995, Galileo of NASA (only spacecraft to orbit Jupiter) revolved around Jupiter and even today is orbiting around the planet. Cassini in 2000 and NASA’s New Horizons spacecraft in 2007 made their flyby across Jupiter.
3. What is Jupiter actually made of?
Jupiter, called the gaseous giant is a gas planet unlike Earth and Mars which are rocky. What does this mean? It means that Jupiter lacks solid surfaces and is gaseous in composition. It’s a humongous gas cloud comprising gases like Hydrogen, Helium (90% Hydrogen, 10% Helium) and few traces of methane, water, ammonia and rock dust. These gases get converted by the immense pressure to liquid as they go deeper into the planet. The core of Jupiter consists of a molten metal, metallic hydrogen and rock materials. It happens to be bigger than our planet Earth and is about three times hotter than the Earth’s core.
4. How many moons does Jupiter have?
Another interesting fact about Jupiter is that it constitutes a miniature solar system within itself. The first four moons of Jupiter were spotted by Galileo and thus are called Galilean satellites. When Galileo made this discovery, he realized that not everything revolves around the Earth in the existing universe. The four moons are named: Io, Europa, Ganymede and Callisto after the Greek Gods and are the largest of Jupiter’s moons. By far, 63 moons have been discovered, most of which have been discovered after 1979.
5. Can we actually see Jupiter?
Yes, Jupiter is so large that we don’t need any telescopes to view it. When we look up to the sky at night, the large bright star that we see is Jupiter. In fact, Jupiter is so large that by merely using a pair of binoculars one can view the yellowish orange colored planet. Wait there’s more!
If you’re a little patient you can even see some of Jupiter’s moons right from your terrace. Since the moons are always in motion, you can see at least one moon at any time you choose. Just place your binoculars on some solid surface and adjust your binocular to the planet. You will be able to see the planet. Cool! Isn’t it? But how will you know which moon your viewing. Thanks to tools like Sky and Telescope’s Jupiter’s moons, we can even obtain information pertaining to the moon we’re viewing.
6. Jupiter is big, but how big?
Jupiter’s mass (1.9 x 1027 kg ) is 318 times the mass of the Earth, and is 2.5 times the mass of the summation of masses of the other 8 planets in the solar system. Wow! Now that’s what you call massive! But here’s another interesting fact about Jupiter: If Jupiter gets any bigger, it’s actually going to start shrinking. Any increase in mass would make the planet more dense resulting in its pulling of itself.
Jupiter is the largest planet in our solar system and is so large that approximately 1300 Earths can fit in it. It’s diameter is 11.2 times of that of the Earth, and its volume is 1321 times the volume of the Earth. If you still haven’t been able to grasp how enormous Jupiter is, then consider the sizes of Watermelon and grape. How a watermelon is to a grape, so is Jupiter to the Earth.
7. What about the rings of Jupiter? Why can’t we see them?
We are used to associating Saturn with rings and have thought of Saturn as the only planet with rings. Jupiter’s ring system was the third ring system to be discovered, after Saturn’s and Uranus’. It was NASA’s Voyager 1 in 1979, that first discovered Jupiter’s faint, fine, dark rings. However, the rings of Saturn and Jupiter have several differences. Saturn’s rings are brighter and made of ice lumps, whereas Jupiter’s rings are darker, comprising dust and rock particles. Jupiter’s rings are not prominent like that of Saturn, and are very difficult to see.
However, thanks to the spacecraft we now know that the rings have three sections. The innermost section: Halo ring which is a fine dough-nut shaped ring composed of fine dust particles. Extending beyond the inner ring is the brightest ring called the main ring and is followed by an outer ring system called the Gossamer ring. The Gossamer ring consists of two rings: inner Amalthea Gossamer ring and outer Thebe Gossamer ring. When the moons are struck by meteors, the dust generated enters the orbits in the form of rings.
8. What about the well-known ‘Great Red Spot’?
Jupiter’s Great Red Spot (GRS) is like the planet’s birth mark and was initially discovered by Giovanni Cassini way back in 1665. Storms are not uncommon on Jupiter’s surface, however, the storms occurring in the GRS region are much more fiercer. Though GRS is merely an oval spot on the planet’s surface, it is two times the size of the Earth. Jupiter’s color ranges from shades of orange, yellow and brown, however, GRS appears to be a darker shade of red.
Astronomers believe this is because GRS draws darker compounds from the planet’s interior, which when exposed to the sunlight become brownish red. Until a century ago, GRS measured up to 40,000 km, however, its size appears to be shrinking and now measures half its size. Astronomers are not sure if this legendary Great Red Spot will disappear forever or not. So if you still haven’t seen it, it’s high time you should before it disappears.
9. How long is a day and a year on Jupiter?
Having the fastest rotation in the entire solar system, a day in Jupiter consists of only 9.9 hours. Due to its fast spinning feature, it is flattened at the poles and bulged at the equator. But here’s the interesting fact about Jupiter: not all parts of Jupiter complete rotating in the same amount of time. For example, the parts near Jupiter’s poles take 9 hours and 56 minutes, whereas the parts near its equator take 9 hours 50 minutes.
Even though Jupiter’s rotation is faster than any other planet, its revolution around the Sun is slow. This is because it is situated far away from the Sun (average of 470 million miles) and as a result takes 11.86 Earth years to complete one revolution. Jupiter follows an elliptical path around the Sun and at its closest point is only 741 million km from the Sun, whereas at its farthest point is 817 million km.
10. Can human beings live on Jupiter?
First and foremost, if at all we get a spacecraft and head for Jupiter, when we land on Jupiter we won’t find any place for landing. Why? Because Jupiter has no solid surfaces and is composed of gases. The gaseous clouds of Jupiter continue to get denser towards the core, thereby resulting into increase in pressure. And what would happen if we tried to jump onto Jupiter’s surface from the spacecraft? We would sink into the clouds and the increase in pressure would crush us to bits. If the increase in pressure somehow fails to kill us, then definitely the high temperatures near the core would vaporize us. So either way we’re doomed!
Another interesting fact about Jupiter is that it sucks anything and everything that’s around it by exerting its tremendous gravitational force on them. Just like how dust gets sucked into a vacuum cleaner, so also asteroids, meteors, comets and other rocky materials traveling around it are seen to be sucked into the planet’s atmosphere.
crazy science facts
In this rare image taken on July 19, 2013, the wide-angle camera on NASA’s Cassini spacecraft has captured Saturn’s rings and our planet Earth and its moon in the same frame. It is only one footprint in a mosaic of 33 footprints covering the entire Saturn ring system (including Saturn itself). At each footprint, images were taken in different spectral filters for a total of 323 images: some were taken for scientific purposes and some to produce a natural color mosaic. This is the only wide-angle footprint that has the Earth-moon system in it.
The dark side of Saturn, its bright limb, the main rings, the F ring, and the G and E rings are clearly seen; the limb of Saturn and the F ring are overexposed. The “breaks” in the brightness of Saturn’s limb are due to the shadows of the rings on the globe of Saturn, preventing sunlight from shining through the atmosphere in those regions. The E and G rings have been brightened for better visibility.
Earth, which is 898 million miles (1.44 billion kilometers) away in this image, appears as a blue dot at center right; the moon can be seen as a fainter protrusion off its right side. An arrow indicates their location in the annotated version. (The two are clearly seen as separate objects in the accompanying narrow angle frame: PIA14949.) The other bright dots nearby are stars.
This is only the third time ever that Earth has been imaged from the outer solar system. The acquisition of this image, along with the accompanying composite narrow- and wide-angle image of Earth and the moon and the full mosaic from which both are taken, marked the first time that inhabitants of Earth knew in advance that their planet was being imaged. That opportunity allowed people around the world to join together in social events to celebrate the occasion.
Views of The Solar System
From Top to Bottom:
Rhea, Mimas, Janus, Pandora and Saturn’s rings.
Tempel 1 after impact and Deep impact tempel 1.
Io, Dione and Hyperion.
Earth, Titan, Mars, and Neptune.
Processing by Gordan Ugarkovic
On July 19, 2013, NASA’s Cassini spacecraft will be turned to image Saturn and its entire ring system during a total eclipse of the sun, as it has done twice before during its previous 9 years in orbit. But this time will be very different. This time, the images to be collected will capture, in natural color, a glimpse of our own planet next to Saturn and its rings on a day that will be the first time Earthlings know in advance their picture will be taken from a billion miles away. A full end-to-end mosaic of images of the ring system will be acquired over 4 hours on July 19. The Earth will be captured in a series of images taken between 21:27 to 21:42 UTC on that day, or 14:27 and 14:42 Pacific Daylight Time.
It will be a day for people all over the globe to celebrate together the extraordinary achievements that have made such an interplanetary photo session possible. And it will be a day to celebrate life on the Pale Blue Dot. Read the press release via CICLOPS.ORG.
The graphics shown below illustrate the position of our planet relative to Saturn, and the portion of Earth that will be illuminated at the time its pictures are captured.
Illuminated View: This graphic shows the view of Earth and the portion of its surface that will be illuminated during the Earth imaging event on July 19, 2013.
Taking Earth’s Picture from Nearly 900 Million Miles Away: This simulated view from NASA’s Cassini spacecraft on July 19, 2013, shows the expected positions of Saturn and Earth around the time Cassini is taking Earth’s picture.
Carolyn Porco: Could a Saturn moon harbor life? | TED
Planetary scientist Carolyn Porco studies and interprets the photos from the Cassini-Huygens mission, orbiting Saturn and its largest moon, Titan. She and a team of scientists from NASA and the European Space Agency have been analyzing the images that Cassini has been sending back since it left Earth in 1999. They’ve found many new rings and four new moons (so far). And they’ve produced breathtaking images and animations of the stormy face of Saturn, its busy rings, and its jumble of moons and moonlets.
Back in the mid-1980s, while still working on her doctorate, Porco was drafted onto a team at JPL that was crunching the mountains of data coming back from the Voyager fly-by of Saturn. Her work on the planet’s “ringlets,” and on a spoke pattern noticed in the rings, made an important connection between Saturn’s rings and its magnetic field — and cemented her connection with Saturn.
Her ongoing work at the Cassini Imaging Central Laboratory for Operations (CICLOPs) has two goals: to process and interpret the Cassini images for other scientists, and to make sure the images — in all their breathtaking poetry and mystery and sheer Save-Image-As-Desktop awesomeness — connect with the general public. She is an advocate for the exploration and understanding of planetary space, and her frequent talks (as well as her “Captain’s Log” memos on the CICLOPS website) speak to everyone, scientist and nonscientist alike.
Still Curious? Watch Carolyn again, this time, LEGO-fied! and watch a conversation with Carolyn, as she discusses the Saturn and Cassini Mission with astrophysicist and curator, Mike Shara of the American Museum of Natural History during the 217th American Astronomical Society meeting in Seattle, Washington
“Imagine the day when we might journey to the Saturnine system, and visit the Enceladus interplanetary geyser park, just because we can.”
I love this woman.