If a planet is found to rotate slower than expected, then astronomers suspect that the planet is accompanied by a satellite, because the total angular momentum is shared between the planet and its satellite in order to be conserved.

: If a planet crosses ( or transits ) in front of its parent star's disk, then the observed brightness of the star drops by a small amount.

If a planet orbits one member of a binary star system, then an uppercase letter for the star will be followed by a lowercase letter for the planet.

If the heavier body is much more massive than the smaller, as for a satellite or small moon orbiting a planet or for the Earth orbiting the Sun, it is accurate and convenient to describe the motion in a coordinate system that is centered on the heavier body, and we say that the lighter body is in orbit around the heavier.

If a planet is sufficiently massive, the water on it may be solid even at high temperatures, because of the high pressure caused by gravity, as it was observed on exoplanets Gliese 436 b and GJ 1214 b.

If ranked today, the United Arab Republic would be the 25th largest nation on the planet ( Egypt is 30th and Syria is 88th ).

If an instantaneous centripetal force ( red arrow ) is considered on the planet during its orbit, the area of the triangles defined by the path of the planet will be the same.

If such a planet actually existed, according to present scientific cosmology, it would be permanently hidden behind the sun but nevertheless detectable from Earth, because of its gravitational influence upon the other planets of the Solar System.

If the orbit is almost edge-on, then the planet can be seen transiting its star.

If not quite a daughter of the soil, she was a granddaughter of it, and her concern for our planet led her to become an environmentalist, indeed the first female environmentalist to achieve such resounding political success.

' If we can get this done, this is going to be the fucking coolest game that the planet Earth has ever fucking seen in its entire history!

Translating this analogy into space, then, a " stationary " observer sees a planet moving left at speed U and a spaceship moving right at speed v. If the spaceship has the proper trajectory, it will pass close to the planet, moving at speed U + v relative to the planet's surface because the planet is moving in the opposite direction at speed U. When the spaceship leaves orbit, it is still moving at U + v relative to the planet's surface but in the opposite direction ( to the left ).

If the spacecraft's purpose is only to fly by the inner planet, then there is typically no need to slow the spacecraft.

If the planet Epsilon Eridani b exists then this belt is unlikely to have had a source outside the orbit of the planet, so the dust may have been created by fragmentation and cratering of larger bodies such as asteroids.

If the eccentricity was actually this high, the planet would pass through the asteroid belt and clear it out within about ten thousand years.

If a large amount of energy is transmitted, it could heat the surface of the planet to an uninhabitable temperature.

Al Gore has argued " If you're a young person looking at the future of this planet and looking at what is being done right now, and not done, I believe we have reached the stage where it is time for civil disobedience to prevent the construction of new coal plants that do not have carbon capture and sequestration.

If the resistance at both wheels is equal, the planet gear revolves without spinning about its own axis, and both wheels turn at the same rate.

If such is the case, the particles within a distance of about Af of the Earth will have, relative to the Earth, a kinetic energy less than their potential energy and they will be captured into orbits about the Earth.

If a rotating frame is chosen so that just the angular position of an object is held fixed, more complicated motion, such as elliptical and open orbits, appears because the centripetal and centrifugal forces will not balance.

If they formed in their current locations, their orbits must originally have been circular ; otherwise accretion ( the coalescence of smaller bodies into larger ones ) would not have been possible because the large relative velocities between planetesimals would have been too disruptive.

If the initial firing is above the surface of the Earth as shown, there will also be elliptical orbits at slower velocities ; these will come closest to the Earth at the point half an orbit beyond, and directly opposite, the firing point.

If a secondary body orbits a primary body, the forces that could tear the second body apart if its strength and internal gravity are not enough, are the tidal force and the " centrifugal force " associated with any rotation of the secondary body about its axis.

* If is a polynomial, then is the boundary of the filled Julia set ; that is, those points whose orbits under iterations of remain bounded.

Note that non-elliptic orbits also exist ; If the eccentricity is greater than one, the orbit is a hyperbola.

If a spacecraft gets close to the Schwarzschild radius of a black hole ( the ultimate gravity well ), space becomes so curved that slingshot orbits require more energy to escape than the energy that could be added by the black hole's motion.

If 0 < e < 1, then the denominator of the equation of free orbits varies with the true anomaly θ, but remains positive, never becoming zero.

If the action is a locally free action or free action, then the orbits of define a foliation of.

If a conjugate of HS in Co < sub > 0 </ sub > fixes a particular point of type 3, this point is found in 276 triangles of type 2-2-3, which this copy of HS permutes in orbits of 176 and 100.

If this refers to the moon's angular width, we can infer that the moon orbits Alofmethbin at a distance of approximately 300, 000 km.

If the mass of the smaller body ( e. g. Earth ) is m, and it orbits a heavier body ( e. g. Sun ) of mass M with a semi-major axis a and an eccentricity of e, then the radius r of the Hill sphere for the smaller body ( e. g. Earth ) is, approximately

If the plane of reference is the equator, these orbits are called equatorial ; if the plane of reference is the ecliptic, they are called ecliptic.

If planets with masses of around an Earth mass or greater form while the gas is still present, the planets are thought to transfer angular momentum to the surrounding gas in the protoplanetary disk so that their orbits spiral gradually inwards towards the primary.

If the planet orbits in the same plane as the circumstellar disk, the inclination would be about 46 °, implying a planetary mass of 1. 5 times Jupiter.

If this happens, one says that " invariants do not separate the orbits ", and the algebra A reflects the topological quotient space X / G rather imperfectly.

If a unipotent group acts on an affine variety, all its orbits are closed, and if it acts linearly on a finite dimensional vector space then it has a non-zero fixed vector.

The theorem is then: If a flow preserves volume and has only bounded orbits, then for each open set there exist orbits that intersect the set infinitely often.

If a child watched its progress he whispered, `` Hay, hay, load of hay -- make a wish and turn away '', and then stared rigidly in the opposite direction until the sound of the horses' feet returned no more.

If `` Jack the Courtier '' is really to be taken as Swift, the following remark is obviously Steele's comment on Swift's change of parties and its effect on their friendship: `` I assure you, dear Jack, when I first found out such an Allay in you, as makes you of so malleable a Constitution, that you may be worked into any Form an Artificer pleases, I foresaw I should not enjoy your Favour much longer ''.

If art is to release us from these postulated things ( things we must think symbolically about ) and bring us back to the ineffable beauty and richness of the aesthetic component of reality in its immediacy, it must sever its connection with these common sense entities ''.

If, as Reid says, `` nearly all his poetry was produced when he was not taking opium '', there may be some reason to doubt that he was under its influence in the period from 1896 to 1900 when he was writing the poems to Katie King and making plans for another book of verse.

If there were no West Berlin problem, imperialist quarters would have invented an excuse for stepping up the armaments race to try to solve the internal and external problems besetting the United States and its NATO partners.

If you do use a cold frame be sure that its ventilation is adequate.

If the temperature is controlled properly, the avocado will delay its ripening until needed.

If the target can change its position significantly during the 30 minutes the missile is in the air on its way, the probability of the missile destroying the target is drastically reduced.

If you can't see your way clear to have summer cooling included when building, by all means make provision for its easy adding later.

If a nation wished to get a head start in physical fitness over all other nations, it would start its kindergarten students on a program of gymnastics the day they entered and thus eliminate a large number of the problems that plague American schools.

If you have a higher-quality product, how can you make it stand out -- justify its premium price -- without the spoken word??

If this seems arbitrary, its effect was to treat citizens of the District of Columbia equally with citizens of the states -- at the expense of expanding a troublesome jurisdiction.

If the transferor has substantial assets other than the claim, it seems reasonable to assume no corporation would be willing to acquire all of its properties in the dim hope of collecting a claim for refund of taxes.

If this threefold division of costs were to have its counterpart in the actual rates of charge for service, as it actually does have in some rates, there would result a three-part rate for any one class of service.

If, however, the figure to be discerned were complicated, composed of several interlocking subfigures, and so on, even the tracing process failed him, and he could not focus even relatively simple shapes among its parts.

If it failed on occasion to elect its candidates for general state offices by majorities, the failure was due to a lingering remnant of the Know-Nothing party, which called itself the American Republican party.

If T is the total `` length '' of the process, its feed state may be denoted by a vector p(T) and the product state by p(Q).

If anti-Semitism was on trial in Jerusalem, why was it not identified, and with enough emphasis to capture the notice of the world press, in its connection with the activities of Eichmann's Department of Jewish Affairs, as exemplified by the betrayal and murder of Jews by non-police and non-party anti-Semites in Germany, as well as in Poland, Czechoslovakia, Hungary??

If, as a home movie maker, you shoot the inevitable footage of your child taking its first steps, you have merely recorded an historical event.

If death receives more than its share of attention from the theologian and if sin receives less than its share, the gift of the life eternal through Christ begins to look like the divinely appointed means of rescue from temporal, i.e., created, existence.

The next traditional step then was to accept it as the authoritative textbook of the Christian faith just as one would accept a treatise on any earthly `` science '', and I submitted to its conditions according to Christ's invitation and promise that, `` If any man will do his will, he shall know of the doctrine, whether it be of God, or whether I speak of myself '' ( John 7: 17 ).

If a man totally ignorant of America were to judge our land and its civilization based on Hollywood alone, what conclusions do you think he might come to??