Is the planet venus seen from earth the whole year round?
> is the planet venus seen from earth the whole year round? Venus is visible most of the year, except for a month or two when it is on the far side of the Sun and a few days when it is between us and the Sun. However its appearance does not fit neatly into Earth's calendar, the two conjunctions mentioned happening at different times every orbit. This December Venus is a "morning star" visible just before sunrise. Next December it will be an evening star; last December it was too close to the Sun to be observed. > is that bright star seen every december during predawn and early evening planet venus? No. It can be several different things, not all of them equally bright. This year Jupiter is an "evening star."
Do the seasons come at the same time everywhere on Earth?
This is an interesting question, because, because it goes back to the original beliefs about seasonal variations, like represented in this little animated special:However the fact However the fact is that seasons are not due to the Earth getting farther away from the Sun; but the length of day changing due to the sunward side of the particular hemisphere likewise changing in angle as the Earth passes from one side of the Sun to the other, as the Earth's equatorial angle to the Sun remains constant according to Newton's first law of motion.This is why the Maya calendar ended on June 21st, because that is when their year ended at the winter solstice. Meanwhile of course, most of the World celebrates the new year at the end of December, because that is shortly after their winter solstice.
Why is it impossible to see all the planets every day?
This is a photo I took on May 3, 2002. It’s a rare opportunity to see all of the visible planets at once (Earth is in the foreground). Jupiter is the bright object high and to the left. The triangle of objects to the right of the tree are, going clockwise from the top, Mars, Venus and Saturn. All but lost in the glare at the far right side of the picture is Mercury. This last part of the grand conjunction is indicative of the problem of seeing objects that are too close to the sun (or when our line-of-sight to the object is too close to the sun). They just get lost in the light coming off the sun.Mercury never gets too high above the horizon as it races around the sun once every 88 days. Venus takes a little less than 225 days. Both of these planets are closer to the sun, so, unlike the outer planets you will never see them at midnight. Mars, Jupiter and Saturn take between ~680 days for Mars to nearly 30 years for Saturn to complete a spin around the sun. So it takes a long time for them to all be in the same part of the sky.
How many days can each of the 'visible planets' be seen per year?
I can give a rough estimate. Saturn is barely visible to the naked eye, so let’s consider the comparitively conspicous naked eye planets.Mercury: You can see in the west sky after sunset and in the east sky just before sunrise. At the (twilight) time, when you can spot Mercury, it will probably be one of the brighest things in the sky. Mercury is always very close to the horizon. You can see Mercury for a few days and it will quickly move to the other side of the sky. I’m guessing you can see Mercury about 50 days a year.Venus: It’s the brightest thing in the sky except for the sun and the moon. Venus’ orbit brings it much more away from the horizon than Mercury and it’s very easy to spot. Like Mercury you can see Venus in the morning sky in the east and evening sky in the west. You can spot Venus for over 200 days a year. As you can see from this image, Venus is too bright to be dimmed out by the moon!Mars: When Mars is close to earth, you can spot it a very bright red star. When it’s not so close, you can still see as a normal red star. Mars can be found pretty much anywhere in the night sky. Mars moves slowly in the sky and in some years, you can see Mars for about 200 days a year.Jupiter: Jupiter is the next brightest thing to Venus. Jupiter can be easily spotted in the sky and can be found anywhere in the night sky. Jupiter can also be seen for about 200 days a year.I’ve been a star gazer for a while and I can quickly identify planets in one glance. Planets have their own characteristics and can be easily distinguished from the background of duller stars.Happy planet hunting, you space explorer! :)
Does the whole planet experience the same seasons at the same time?
No. You thought wrong. The seasons have nothing to do with the planet's distance from the Sun. The seasons are caused by the tilt of the Earth's axis. The Earth's rotational axis is tilted about 23 degrees away from being perpendicular to its orbit. This means that different parts of the planet receive more or less direct sunlight at different times of the year. When the northern hemisphere is tilted toward the Sun, it receives more direct sunlight and the climate is warmer. At the same time, the southern hemisphere is tilted away from the Sun, so it receives less direct sunlight and the climate there is cooler.
Which planet do we see only during the dawn or sunset when the sun is safely below the horizon?
If it’s really bright and white - brighter than any of the stars in the night sky - it’s most probably Venus. Its orbit is closer to the Sun than Earth’s, so it’s never opposite from the Sun in the sky but always to be found more or less in the same direction. Hence it's either visible before sunset or after sunrise.Besides Venus there's Mercury. It's even closer to the Sun and much dimmer than Venus. It looks more or less like a regular star. Because of this, it's actually quite hard to spot unless you know where (and when, Mercury moves fast and is usually only visible for a few weeks at a time) to look.The other naked eye planets (Mars, Jupiter and Saturn) are also occasionally (for a few months every year or there about) to be found near the Sun in the sky. Especially Jupiter is a very bright object and it's possible someone mistakes it for Venus.
Do Planetary positions Repeat?
There is this silly cliche that says given an infinite number of monkeys and an infinite number of typewriters (I'm dating myself; substitute "word processors"), sooner or later one of them will write all the works of Shakespeare. So yeah, given enough time, I suppose they will repeat or get close. But those time periods would be so far apart, there is no sensible way to compare "then" and "now" or "now" and "later." On the other hand I'm convinced that there are few and possibly no actual time twins. Time Twins are two (or more) people born at precisely the same instant in the same place. My experience is not universal, but I've never seen the charts of time twins or even close. However, close does exist. I have seen a photograph of two girls, born on Feb 20 1947 at the same hospital within five minutes of each other, and although they are not related by blood, they look like identical twins or did when the photo was taken at about age 8 or 9 (see below). So-called "Time Twin Studies" have been shown to use subjects that were born hours apart and in some cases months apart. There just aren't that many, if any, documented cases of Time Twins. I was born in a major metropolitan area (high population), and I've volunteered data for every Time Twin Study I could find before and after the Internet (don't bother. I no longer do it. There was no identity theft at the time). I've never found a single Time Twin that way, and only a few that were born the same day I was. EDIT: I should clarify: I don't discount the possibility of time twins. I just doubt the idea that there are very many of them unless the definition of Time Twin is stretched out to include a lot of births.
Describe the shape of the ellipse a planet forms if its orbital velocity remains the same during one complete orbit of its star.?
If the orbital velocity remains constant for an entire orbit, the shape is a perfect circle. -------- In case you don't understand WHY everyone told you it's a circle: For any orbit around a single body, the area of the shape swept out by the orbital body over any given length of time is equal at every point on the orbit for the same length of time. This is accomplished by the orbital velocity changing at different points in a well-defined way. Which means when the body is closer to the center it has a higher velocity so it sweeps out a shorter, fatter area - while when it's farther from the center it has a lower velocity, so it sweeps out a longer, narrower area. The only way for the velocity to remain constant at every point in the orbit is for the distance from the center to remain constant as well. And the geometric shape in which a closed loop has every point at the same distance from a single center - is a circle. In the diagram below, the two shaded areas are equal, because planet1 orbits faster through A1 than through A2, though they take the same amount of time.
What time of the year is Saturn visable?
The "planets" are aptly named. Planet, being derived from "wanderer." http://www.etymonline.com/index.php?term... All of the planets appear to move about the celestial sphere, (close to the ecliptic) as they orbit the sun. So there is never a set "time of year" a planet is visible. Saturn takes about 29 years to complete its orbit around the sun. Over that 29 year period, it will complete a "tour of our sky." So that, some years it will be visible in say, the direction of Gemini, and other years (such as 2009) it will be in the direction of Leo. Roughly once per year, for about a month or so (sometimes a little less, depending on when you wake up, and depending on Saturn's inclinational position in its orbit) Saturn will not be visible, or at least difficult to observe, because it lies to closely to the sun. I would highly recommend downloading the software at stellarium.org You can set any location you wish, and any date and time you wish, and the night sky will be displayed for you neatly on an easy to read sky map.