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A Sun-synchronous orbit (sometimes incorrectly called a heliosynchronous orbit) is a geocentric orbit which combines altitude and inclination in such a way that an object on that orbit ascends or descends over any given point of the Earth's surface at the same local mean solar time. The surface illumination angle will be nearly the same every time. This consistent lighting is a useful characteristic for satellites that image the Earth's surface in visible or infrared wavelengths (e.g. weather and spy satellites) and for other remote sensing satellites (e.g. those carrying ocean and atmospheric remote sensing instruments that require sunlight). For example, a satellite in sun-synchronous orbit might ascend across the equator twelve times a day each time at approximately 15:00 mean local time. This is achieved by having the osculating orbital plane recess (rotate) approximately one degree each day with respect to the celestial sphere, eastward, to keep pace with the Earth's revolution around the Sun.[1]

The uniformity of Sun angle is achieved by tuning the inclination to the altitude of the orbit (details in section "Technical details") such that the extra mass near the equator causes orbital plane of the spacecraft to precess with the desired rate: the plane of the orbit is not fixed in space relative to the distant stars, but rotates slowly about the Earth's axis. Typical sun-synchronous orbits are about 600-800 km in altitude, with periods in the 96-100 minute range, and inclinations of around 98° (i.e. slightly retrograde compared to the direction of Earth's rotation: 0° represents an equatorial orbit and 90° represents a polar orbit).[1]

Special cases of the sun-synchronous orbit are the noon/midnight orbit, where the local mean solar time of passage for equatorial longitudes is around noon or midnight, and the dawn/dusk orbit, where the local mean solar time of passage for equatorial longitudes is around sunrise or sunset, so that the satellite rides the terminator between day and night. Riding the terminator is useful for active radar satellites as the satellites' solar panels can always see the Sun, without being shadowed by the Earth. It is also useful for some satellites with passive instruments which need to limit the Sun's influence on the measurements, as it is possible to always point the instruments towards the night side of the Earth. The dawn/dusk orbit has been used for solar observing scientific satellites such as Yohkoh, TRACE,Hinode and Proba-2, affording them a nearly continuous view of the Sun.[citation needed]

Sun-synchronous orbits are possible around other oblate planets, such as Mars. But for example Venus is too spherical for having a satellite in sun-synchronous orbit

A polar orbit is an orbit in which a satellite passes above or nearly above both poles of the body (usually a planet such as the Earth, but possibly another body such as the Sun) being orbited on each revolution. It therefore has an inclination of (or very close to) 90 degrees to the equator. Except in the special case of a polar geosynchronous orbit, a satellite in a polar orbit will pass over the equator at a different longitude on each of its orbits.

Polar orbits are often used for earth-mapping, earth observation, and reconnaissance satellites, as well as for some weather satellites. The Iridium satellite constellation also uses a polar orbit to provide telecommunications services. The disadvantage to this orbit is that no one spot on the Earth's surface can be sensed continuously from a satellite in a polar orbit.

It is common for near-polar orbiting satellites to choose a sun-synchronous orbit: meaning that each successive orbital pass occurs at the same local time of day. This can be particularly important for applications such as remote sensing of the atmospheric temperature, where the most important thing to see may well be changes over time, which you do not want to see aliased onto changes in local time. To keep the same local time on a given pass, it is desirable for the orbit to be as short as possible, which is to say as low as possible. However, very low orbits of a few hundred kilometers would rapidly decay due to drag from the atmosphere. A commonly used altitude is approximately 1000 km; this produces an orbital period of about 100 minutes.[1] The half-orbit on the sun side then takes only 50 minutes, during which local time of day does not greatly vary.

To retain the sun-synchronous orbit as the Earth revolves around the sun during the year, the orbit of the satellite must precess at the same rate. Were the satellite to pass exactly over the pole, this would not happen. But because of the Earth's equatorial bulge, an orbit inclined at a slight angle is subject to a torque which causes precession; it turns out that an angle of about 8 degrees from the pole produces the desired precession in a 100 minute orbit.[1]

A satellite can hover over one polar area a large part of the time, albeit at a large distance, using a polar highly elliptical orbit with its apogee above that area. This is the principle behind a

A polar orbit is an orbit in which a satellite passes above or nearly above both poles of the body (usually a planet such as the Earth, but possibly another body such as the Sun) being orbited on each revolution. It therefore has an inclination of (or very close to) 90 degrees to the equator. Except in the special case of a polar geosynchronous orbit, a satellite in a polar orbit will pass over the equator at a different longitude on each of its orbits.

Polar orbits are often used for earth-mapping, earth observation, and reconnaissance satellites, as well as for some weather satellites. The Iridium satellite constellation also uses a polar orbit to provide telecommunications services. The disadvantage to this orbit is that no one spot on the Earth's surface can be sensed continuously from a satellite in a polar orbit.

It is common for near-polar orbiting satellites to choose a sun-synchronous orbit: meaning that each successive orbital pass occurs at the same local time of day. This can be particularly important for applications such as remote sensing of the atmospheric temperature, where the most important thing to see may well be changes over time, which you do not want to see aliased onto changes in local time. To keep the same local time on a given pass, it is desirable for the orbit to be as short as possible, which is to say as low as possible. However, very low orbits of a few hundred kilometers would rapidly decay due to drag from the atmosphere. A commonly used altitude is approximately 1000 km; this produces an orbital period of about 100 minutes.[1] The half-orbit on the sun side then takes only 50 minutes, during which local time of day does not greatly vary.

To retain the sun-synchronous orbit as the Earth revolves around the sun during the year, the orbit of the satellite must precess at the same rate. Were the satellite to pass exactly over the pole, this would not happen. But because of the Earth's equatorial bulge, an orbit inclined at a slight angle is subject to a torque which causes precession; it turns out that an angle of about 8 degrees from the pole produces the desired precession in a 100 minute orbit.[1]

A satellite can hover over one polar area a large part of the time, albeit at a large distance, using a polar highly elliptical orbit with its apogee above that area. This is the principle behind a

A polar orbit is an orbit in which a satellite passes above or nearly above both poles of the body (usually a planet such as the Earth, but possibly another body such as the Sun) being orbited on each revolution. It therefore has an inclination of (or very close to) 90 degrees to the equator. Except in the special case of a polar geosynchronous orbit, a satellite in a polar orbit will pass over the equator at a different longitude on each of its orbits.

Polar orbits are often used for earth-mapping, earth observation, and reconnaissance satellites, as well as for some weather satellites. The Iridium satellite constellation also uses a polar orbit to provide telecommunications services. The disadvantage to this orbit is that no one spot on the Earth's surface can be sensed continuously from a satellite in a polar orbit.

It is common for near-polar orbiting satellites to choose a sun-synchronous orbit: meaning that each successive orbital pass occurs at the same local time of day. This can be particularly important for applications such as remote sensing of the atmospheric temperature, where the most important thing to see may well be changes over time, which you do not want to see aliased onto changes in local time. To keep the same local time on a given pass, it is desirable for the orbit to be as short as possible, which is to say as low as possible. However, very low orbits of a few hundred kilometers would rapidly decay due to drag from the atmosphere. A commonly used altitude is approximately 1000 km; this produces an orbital period of about 100 minutes.[1] The half-orbit on the sun side then takes only 50 minutes, during which local time of day does not greatly vary.

To retain the sun-synchronous orbit as the Earth revolves around the sun during the year, the orbit of the satellite must precess at the same rate. Were the satellite to pass exactly over the pole, this would not happen. But because of the Earth's equatorial bulge, an orbit inclined at a slight angle is subject to a torque which causes precession; it turns out that an angle of about 8 degrees from the pole produces the desired precession in a 100 minute orbit.[1]

A satellite can hover over one polar area a large part of the time, albeit at a large distance, using a polar highly elliptical orbit with its apogee above that area. This is the principle behind a

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How is a weather satellite in polar orbit able to view Earths surface?

From the question, I'm guessing that when the questioner reads the term "polar orbit", he's picturing the satellite doing a little tiny circle in the sky over the North Pole. This is not an accurate understanding of the term. Remember that the center of the orbit of an artificial satellite has to be at the center of the earth. A 'polar orbit' is an orbit that covers both poles. If you picture the globe of the earth, the satellite's orbit is a circle standing up, with the satellite traveling up and down, passing over both poles in each complete revolution of the earth. As the earth rotates, every point on earth passes under the orbit, and sooner or later, every point on earth will be visible from the satellite.


Is the orbit for a tv satellite called a polar orbit?

A polar orbit (as opposed to an equatorial orbit) passes over the poles, north and south. A low orbit is relatively close to the Earth (or other object being orbited), it might be a few hundred miles up.


How do satellites in low polar orbit scan the whole world in one day?

A satellite in a "polar" orbit goes north and south around the world. Depending on the satellite's altitude, it will take about 90 minutes to go around once. But because the Earth itself spins from West to East, every time the satellite comes back around, the Earth will have rotated underneath it, by 360 degrees divided by the orbital period in minutes; for a 90-minute orbit, about 23 degrees per orbit. You can see how this would work if you take some string or ribbon, and wrap it top-to-bottom around a ball. Be sure to spin the ball slowly while wrapping it with the string.


What is the difference between a goes satellite and a poes one?

The GOES are as they say, Geostationary 22,300 miles above the Earth's surface. Gathering information every 15 to 30 minutes. The POES are Polar-Orbiting because the orbit from one polar regoin to the next staying mostly parallel to the meridian line 530 miles above Earth's surface. With the Earth's rotation from west to east the images observe to the west of the last scanned area. The satellites orbit 14.1 times a day putting them at different locations at different times of the day.


Does antarctica have a polar climate?

Antarctica does have a polar climate.

Related questions

What type of orbit is used by gps satellites subsynchronous or sunsynchronous?

Geostationary satellites are the ones used for GPS satellites.


What is the polar orbit used for and why?

A polar orbit is used for Earth observation satellites and weather satellites because it covers the entire surface of the Earth. It allows these satellites to pass over both the North and South Poles, providing global coverage of the planet.


What is polar orbit and geo-stationary orbit?

A satellite in polar orbit passes over the poles.A geosynchronous orbit follows the equator and at such an altitude its orbital period is one day long and remains in the same position relative to the ground.


Some satellites are put into an orbit around the earths poles what is this type of orbit called?

A satellite orbiting around the Earth's poles is in a polar orbit. This type of orbit allows the satellite to pass over different parts of the Earth as it rotates below. Polar orbits are often used for Earth observation and surveillance satellites.


What is the difference between sun synchronous polar orbit and a synchronous polar orbit?

A sun-synchronous polar orbit is one where the satellite passes over any given point on Earth at the same local mean solar time, enabling consistent lighting conditions for imaging. A synchronous polar orbit, on the other hand, would require the satellite to orbit at the same speed as the Earth's rotation, which is not practical for polar orbits due to the high latitudes involved.


What is a polar orbit used for?

A polar orbit is used for various purposes, such as Earth observation, weather monitoring, and environmental research. It provides global coverage as it allows a satellite to pass over the entire surface of the Earth while remaining in a north-south direction. This type of orbit is particularly useful for capturing images of the entire planet or studying changes in polar regions.


List of polar or non-polar formulas?

Polar Molecules:· Water (H20): it is planar triangular, and the electrons orbit more around the O than the 2 H's· Nitrogen Hydroxide (NH3): Planar triangular, electrons orbit more around the N that the Hydrogen· Sulfur Dioxide (SO2): Planar triangular, electrons orbit more around Sulfur than the oxygen.· Hydrogen Sulfide (H2S): Planar triangular, electrons orbit more around Hydrogen than sulfur.· Bromine Trichloride (BCl3): planar triangular, electrons orbit more around Bromine.Non Polar Molecules:· Dihydrogen (H2): Linear and electrons orbit evenly · Carbon Dioxide (CO2): Linear, equal orbit· Carbon Monoxide (CO): linear, equal distribution·


What type of orbit does a weather satellite have and why?

The polar orbit so that it can measure cold and hot points around the entire earth :)


How many times does polar satellites orbit the earth?

As many times as necessary in order to get the ground map. I am no expert but one orbit from north to south (since this is polar) must depend on the impulse provided by the final kick to put it into polar orbit. TLDR is varies (I believe this is referred to as it's period) try examining various polar sats on file at wiki to see if this is correct. I to would like to know!


Which polar launch vehicle put chandrayaan-1into orbit?

PSLV-C11


Why a polar orbit is not suitable for satellite television?

it is too cold and there is no power lines to get signal


Which orbit would be best for investigating the Arctic and Antarctic?

If the satellite is in an orbit that takes it over the North and South Poles, it will eventually cover all parts of the Earth as the Earth spins beneath it. This kind of orbit is called a polar orbit.