Would it be possible to find planets by detecting their magnetic core?
472120
No.  Even if they did have a magnetic core (Venus doesn't by the way), their magnetic field would be "washed out" by the magnetic field of the stars they orbit.\n\nIt is simply easier to look for shadows on the stars to find planets.
839196
It is more likely than not that there are many planets in the universe with life and many of those may have "intelligent" life.\n\nWe have just only obtained the ability to detect planets in other solar systems and we can only detect very large ones. We do not have the ability to detect Earth like planets.\n\nWithin our own solar system, we have yet to find undisputable evidence of life on any of the planets we have activley searched for it. Many scientists are optimistic about finding microbial life forms within our solar system though. There are still pleanty of places on Mars, for example, that we simply haven't looked, and there are many moons in our solar system with the potential for supporting microbial, and even more complex life forms. Jupiter's moon Europa is a good candidate because it is covered by a sheet of ice and thought to have liquid water oceans underneath. Due to Jupiter's gravity constantly tugging on the planet, it is likely geologically active and thermal vents may exist in it's under ice oceans. Here on Earth, underwater thermal vents are teeming with life, even though no sun light reaches them.
730051
I have read that the gaseous planets don't have a rocky core like the inner planets Mercury, Venus, Earth, & Mars. What scientists theorize is that they have a slushy sphere of ammonia, iron, and a number of elements that may be larger than our planet. But as the first answer correctly states is that there is no known boundary or crust to make an accurate measurement from for now.
347063
Well extraterrestial planet hunting is only just beginning to be able to discover "smaller" planets. As before only the giant ones indicated their presence, by the effect of their gravity on the parent star.\nRemember even the most powerful telescopes on earth merely see a distant star as a point of light.\nAs for a signal, surveillance equipment is steadily becoming more sophisticated, and discoveries are continously being made to enhance the resolving power of the apparatus. \nMy view is life will not be that common, but a fair few systems will have, or have had life on them at some point. I am sure that in the next twenty years, an umistakeable signal, either intentional or not will be received on earth, and we will know that we are not alone.
41352
Well, the diameter of the planet is 12,756.3 km.  That would make the radius approximately 6,378 km.  So the radius shoud be an approximation of the distance between the inner core and the surface.\n\nAh ha!  I just look it up and I was right! "Inner core (5000 km - 6370 km below the Earth's surface)."\n:o)
678310
WHEN YOU ARE ON EARTH U CANT FIND ANY POINT. YEAH I THING IS POSSIBLE. U CAN PURCHASE A GLOBE AND ROTATE IT. U WILL FIND ROTATION THERE.!
285416
We really only know our solar system planets, and we know from probes that have been sent, from the effects on their moons and other bodies coming close or even hitting into them. We can observe how the spectrum of the atmosphere changes when the planet goes behind or for Mercury and Venus, in fron of, the sun's halo. Or when the planet "occults" another star whose spectrum is known.
251207
Don't have it handy,but it'sjust a little denser than water, from what I remember. Check www.nasa.gov. They have lots of planetary info!
1000403
What sort of features are you hoping to see? An 80mm would be enough to see the red spot on Jupiter and the rings of Saturn. It probably won't make out the Cassini division in the rings, though.  You should also be able to see cloud bands on Jupiter. When looking at Mars, you might be ble to see some dark splotches during excellent seeing conditions, but Mars is a hard object for everyone. The most you will ever see on Venus is the phase because the clouds obscure everything else. Mercury is a hard object and is way too small to see anything. Uranus will be a blue dot as will Neptune. You won't see Pluto.\n\nI hope this helps!
789662
Earth: The Lone Pale Blue Dot?\nNovember 02, 2006 \n\nA recent photo from the Cassini spacecraft shows the mighty planet Saturn, and if you look very closely between its wing-like rings, a faint pinprick of light. That tiny dot is Earth bustling with life as we know it. The image is the second ever taken of our world from deep space. The first, captured by the Voyager spacecraft in 1990, stunned many people, including the famous astronomer Carl Sagan who called our seemingly miniscule planet a "pale blue dot" and "the only home we've ever known." \n\nLast September, a portion of Cassini's picture showing Earth was unveiled to an auditorium full of scientists attending the third Pale Blue Dot workshop at the Adler Planetarium in Chicago. The workshop brought together scientists from across the country and beyond to talk about how to find life elsewhere in our universe, a central theme in the interdisciplinary field of astrobiology. When the workshop participants were presented with the picture, they spontaneously began to clap. One of their fundamental goals is to capture a portrait like Cassini's showing another "pale blue dot" like Earth in a planetary system beyond our own. \n\nIf scientists do ever acquire such a photo, how will they figure out whether anybody is home? Workshop participant Dr. Wes Traub of NASA's Jet Propulsion Laboratory in Pasadena says a photo of a light-blue extrasolar planet - a planet outside our solar system - might indicate the planet has an atmosphere, a tantalizing sign that it could support life. "In our solar system, we are the only small light-blue planet," he said. Earth appears blue because its atmosphere scatters blue light around, literally filling the sky with the color blue. \n\nBut colors are only clues. A planet with an atmosphere might be blue, or not. Mars has an atmosphere, albeit a thin one, and it's red. The blue light in the martian skies is soaked up by iron-containing molecules on the surface that radiate red. \n\nUltimately, astrobiologists will need additional data to determine whether an extrasolar planet is habitable, and if so, whether it harbors life. Future planet-finding missions like NASA's Terrestrial Planet Finder are expected to return both valuable "spectral" data and imagery of planets looking small enough to fit on a pin. Spectra are surveys of an object's rainbow-like array of different wavelengths of light. They reveal the presence of specific molecules. \n\nTo determine if a planet is livable, scientists will look for carbon dioxide and water vapor, signposts that a planet has an atmosphere and oceans, respectively. Atmospheres not only provide air to breathe, but also act like blankets to keep a planet warm and help buffer potential residents from damaging ultraviolet and cosmic rays. Oceans help regulate a planet's temperature and provide liquid water, an essential ingredient for life on Earth. \n\nOther molecules enveloping a planet, such as oxygen, ozone and methane, can suggest that life itself has taken root. On Earth, oxygen is "breathed out" by plants, and methane by micro-creatures living in swamps and animals. These chemicals don't stick around for long on their own, so if they are hanging around an extrasolar planet, then something must be pumping the stuff out. That something could be life, but this isn't always the case. Saturn's moon's Titan is shrouded in an atmosphere containing lots of methane not produced by life. \n\nScientists say that oxygen is a more reliable sign of life than methane, but if they found large quantities of both, they'd be more convinced. "Finding two of these molecules together would be much better than one. The more, the better," said Dr. Victoria Meadows of NASA's Spitzer Science Center, Pasadena, who served as chair of the third Pale Blue Dot conference. "For example, if we found carbon diox
1005733
Since most people have either accurately or sarcastically answered your question, here is some fun things you can look for while planet gazing.  \n\nThe inner planets (Mercury & Venus) will show you phases the same as the moon has except when they get close to a full "planet" (like a full moon) they will be very close to the other side of their orbit and will be difficult to see due to being close to the sun.  The closer in the orbit crescents are more interesting anyway.  On the outer planets, Mars will be reddish with some darker parts and sometimes you can see the polar "ice" caps (said to be frozen carbon dioxide).  Jupiter (the largest) has the ongoing "red spot" (thought to be a giant storm) that passes around it.  Another interesting Jupiter tidbit is you can clearly and easily see four of its moons (which will change position from night to night) with just a moderately powerful telescope.   Saturn has, of course, it's rings which will be at different angles of view depending on what part of its orbit it's in.  The rest (Uranus, Neptune and Pluto) are very, very distant and extremely difficult to see with anything except very expensive equipment. \n\nAnd don't just focus on the planets.  There is a multitude of clusters , galaxys, multiple star systems and nebulae to check out (not to mention the occasional comet and meteor shower that comes now and then)\n\nHope you have fun with it...
788348
All highly speculative give our limited time recording history.\n\nHowever, loss of circulation in the core would lead to loss of magnetic shielding and heavy flux of solar wind. It is believed this will make life very difficult for surface dwellers. Since the field is now weakening and is expected to pass through a minimum within the next few thousand years, we won't have to wait for hundreds of millions of years to find out!\n\nAlso given what little history we know, we expect that a few really big geologic shocks are in store before the end and our civilization isn't likely to make it through those. i.e. we're F'd before any of the really long term (and hard to predict) ends come about
908949
well, maybe not a huge ice block, but certainly an ice sphere.  Pluto (although not new, and I believe has recently been stripped of its planet status) is basically pure ice as far as we know, with possibly a small rocky core.  The further you get from the sun the more icy the planets will be and the closer you get the more rocky, you'll find more gaseous planets in the middle.  If you want to name 10 new planets around our solar system, then you can probably go to the nasa website or space.com and research the many pluto-style "planets" that have been found beyond our 8 planets, one of the largest thus far is at least temporarily dubbed xena, but there are many others like it that have been discovered.  If you want to know how our solar systems planets were named, again the nasa website is great or just type in the planets name on google and it will give you a lot of information.  Good luck to you and have fun!
783545
Like the Earth, Mercury has an iron core. But Mercury's core occupies proportionately more (3/4) of the planet's diameter than Earth's does (about half). You can think of Mercury as a metal ball the size of the Moon surrounded by about 700 kilometers (430 miles) of rocky crust. The large relative size of Mercury's core makes it the most iron-rich planet in the solar system, with iron accounting for 65-70% of the planet's mass. Mercury's abundance of iron resulted from its position near the Sun. When the planets were forming out of the same cloud of gas and dust as the Sun, the temperatures in the warm inner regions of the primordial solar nebula were so high that iron-rich minerals were just about the only ones that could condense into solids. Farther away from the Sun, other minerals could also condense. Thus the iron content of the rocky planets in the solar system decreases with increasing distance from the Sun.\n\nMercury's iron core may also be responsible for one of the most surprising findings from Mariner 10 — the planet's weak magnetic field, 100 times weaker than Earth's. Astronomers and geologists are still trying to figure out what causes Mercury's field. In the case of the Earth, rapid rotation of its molten iron core generates electrical currents which produce the Earth's magnetic field. But Mercury is so small, astronomers had assumed its core had cooled and solidified. Plus, it rotates too slowly to generate a magnetic field the way the Earth does. Or so they thought. Perhaps Mercury's core is still partially liquid, or perhaps the magnetic field is "left over'' from an earlier time when the iron core was molten. Astronomers continue to work on this puzzle.
167190
Some things in science have obvious applications. Some things do not and are just knowledge for knowledge's sake. I think that knowledge of the center of the earth falls in that second category; there is no immediate obvious spin-off from knowing about the center of the earth. However, there are potential and indirect reasons why one might want to know about it:\n\n1. Knowledge about the structure of the earth helps us understand how the earth and possibly other planets came to be. We really do not understand much about planetary formation. This knowledge is not directly applicable, but we might need to know where to look in the rest of the universe for other earth-like planets, and knowledge of how planets form could help. This would be in the distant future, if at all. \n\n2. The dynamo that produces the earth's magnetic field is in the core of the earth, and knowledge about the core helps us understand more about the dynamo. This can lead to a better understanding of the sun and its dynamo, and the relation of the sun's dynamo to controlled fusion, which we have not been able to produce here on earth yet, but which would help us meet our energy needs. So there are possible connections with energy production. \n\n3. The earth's core contains some very hot fluids circulating around, and we do not understand much about the physics of these materials. Various engineering projects that use these, like the cooling systems of breeder reactors might be able to use this information. \n\n4. To learn about the earth's core, we have to develop better observational and modeling tools, which can be useful for other more applied projects. \n\n5. The core is not necessarily disconnected from the mantle, and what happens in the core probably affects what happens in the mantle, including hotspots (that create volcanoes) and plate tectonics (that cause earthquakes and tsunamis). Understanding the dynamics of the earth's interior might give us insight into eventually understanding and even possibly predicting some aspects of these very dangerous natural phenomena. \n\nI could probably come up with many more ideas, but this is a start. So even though one might be tempted to say "the core? what does it have to do with anything?", it is not necessarily true. There are all kinds of potential connections between different fields of science, and one has to look at things with an open mind.
1075736
So far, we can only detect fairly large planets around nearby stars in our own galaxy.  However, the number of planets we are discovering shows us that planets are very common.  There is no reason to think that other galaxies would be any different.\n\nWe don't have sensitive enough tools yet to detect Earth-like planets, but they probably exist. We don't yet know how common life, intelligent or otherwise, is in the universe, but considering how many galaxies there are and how many stars in each one, it seems as though there should be other intelligent beings out there somewhere.
49306
It depends on what you mean by earth-like. There have been a few planets that might not be gas giants and are reasonably close to their central stars so they will not be too cold discovered in extrasolar star systems. \n\nI have attached a link to a story about the most recently discovered "earth-like" planet. However, it has a "year" that is only 10 days long, and the surface is over 1000 degrees Fahrenheit, so it is not that much like earth.