If enough electricity is provided by solar panels, wind turbines, or other means, then electric heaters and stoves become a practical autonomous design.

If a main-sequence star is not too massive ( less than approximately 8 solar masses ), it will eventually shed enough mass to form a white dwarf having mass below the Chandrasekhar limit, which will consist of the former core of the star.

If the solar year is defined as a tropical year, then a lunisolar calendar will give an indication of the season ; if it is taken as a sidereal year, then the calendar will predict the constellation near which the full moon may occur.

If a powerful solar magnetic storm is born, they can warn Earth in advance.

If the core of the star is not too massive ( less than approximately 1. 4 solar mass, taking into account mass loss that has occurred by this time ), it may then form a white dwarf ( possibly surrounded by a planetary nebula ) as described above for less massive stars, with the difference that the white dwarf is composed chiefly of oxygen, neon, and magnesium.

If the mass of the progenitor is above 8 solar masses but below 10. 5 solar masses, the core temperature suffices to fuse carbon but not neon, in which case an oxygen-neon – magnesium white dwarf may be formed.

( If its begin and end are defined using mean solar time ( the legal time scale ) then its duration was 31622401. 141 seconds of Terrestrial Time ( or Ephemeris Time ), which is slightly shorter than 1908 ).

" If a magnetic sail orients at an angle relative to the solar wind, charged particles are deflected preferentially to one side and the magnetic sail is pushed laterally.

If the example were set in the solar system, the drag force, d / dt ( mv < sub > 1 </ sub >), would be about ( 0. 001 kg / s ) ( 500, 000 m / s ), or 500 newton.

If instead of mean solar day we use the sidereal year as our time unit, the value of ks is very close to 2π ( k = 6. 28315 ).

If there is enough solar energy in the atmosphere, however ( on a hot summer's day, for example ), the moisture from one storm cell can evaporate rapidly — resulting in a new cell forming just a few miles from the former one.

If a planet's magnetic field is strong enough, its interaction with the solar wind forms a magnetosphere.

If the islanders were not able to pay for solar lanterns with cash, reasoned the project developers, they can pay with crops

If a solar eclipse occurs at one new moon, which must be close to a node, then at the next full moon the Moon is already more than a day past its opposite node, and may or may not miss the Earth's shadow.

: If this were a new religion, invented to satisfy our modern scientific conceptions, we could not find a flaw in the correctness of this view of the energy of the solar system.

* If the foreign audience is more than 1, 000 kilometers away from the broadcaster, shortwave radio is reliable, but subject to interruption by adverse solar / geomagnetic conditions.

If the solar wind has energetic bursts, contracting and expanding the magnetosphere, or if the solar wind takes a southward polarization, geomagnetic storms can be expected.

If solar power is used as a heat source, regular solar mirrors and solar dishes may be utilsed.

In 1899, Flinders Petrie wrote: If this were a new religion, invented to satisfy our modern scientific conceptions, we could not find a flaw in the correctness of this view of the energy of the solar system.

Dr Edleston, in his preface to Newton's correspondence with Cotes, justly remarks: " If Flamsteed the Astronomer-Royal had cordially co-operated with him in the humble capacity of an observer in the way that Newton pointed out and requested Of him ... the lunar theory would, if its creator did not overrate his own powers, have been completely investigated, so far as he could do it, in the first few months of 1695, and a second edition of the Principia would probably have followed the execution of the task at no long interval.

If the Earth had no Moon, the ocean tides resulting solely from the Sun's gravity would be only half that of the lunar tides.

If the ecclesiastical lunar calendar is accurate, the ecclesiastical new moon can be any day from the day of the astronomical new moon or dark moon to two days later ( see table ).

If the Serpent Mound were designed to sight both solar and lunar arrays, it would be significant as the consolidation of astronomical knowledge into a single symbol.

# If 1, 978 is multiplied by 365. 2422 days ( the number of days in a solar year, not to be confused with the lunar year ), the result is 722, 449.

If the positions of the observing locations are measured, the timings can be analyzed afterwards to obtain a very accurate fix of the position of the Moon relative to the star and to determine the details of the lunar mountains and valleys seen in profile along the moon's edge.

:" If you get acquainted with the religion of the Karaites, we can see that their Bible was considered the Pentateuch, that they recognized Jesus Christ a prophet, but a prophet considered equally and Mohammed, they believe in reincarnation, that their holidays are on the lunar calendar, the status of women and before and after marriage, based on the teachings of Muhammad that kenasy built as a mosque, " fountain ", and was a special room for washing by type Mohammedan, when logging in kenasy remove your shoes, like the Mohammedans.

If it is taken as 940 lunations less one day then the Callippic mean year will be shortened by 1 / 76 day ( 18 minutes 57 seconds ), making it grossly too short, and it will also grossly drift ahead with respect to the mean lunar cycle at the rate of 1 / 940 of a day ( 1 minute 31 seconds ) per lunar month.

If the cycle length is truncated to 27, 758 days then the mean year is 365 days 5 hours 41 minutes 3 seconds, or almost 8 minutes too short per year, and it will drift ahead of the mean lunar cycle by about ( 3 / 4 )/ 940 day ( 1 minute 9 seconds ) per lunar month.

If the signal is red ( or double red ), with or without a lunar white, the trip arm rises enough for its crossbar to strike a " trip valve " or " tripcock " lever on the bottom of a train's first car as it passes ; and by doing so triggers the emergency brakes of the train.

" If I Forget Thee, Oh Earth " is the story of Marvin, a child who lives in a lunar colony.

If within one year you can make a success out of the American, you can practically name your own salary thereafter.

If the railroads, for example, regularly slaughtered 25,000 passengers each year, the high priests of the cult would have cause to tremble for their personal safety, for such a holocaust would excite demands for the hanging of every railroad president in the United States.

If, in the trustee's judgment, `` reasonable market conditions '' did not prevail during any given year, he was to be allowed to petition the court for an extension of time within the ten-year period.

If you use a fiscal year, a year ending on the last day of any month other than December, your return is due on or before the 15th day of the 4th month after the close of your tax year.

If you were required to file a declaration of estimated tax for the calendar year 1961, it is not necessary to pay the fourth installment otherwise due on January 15, 1962, if you file your income tax return Form 1040, and pay your tax in full for the calendar year 1961 by January 31, 1962.

If you are a nonresident alien and a resident of Puerto Rico, your return is also due June 15, 1962, or the 15th day of the 6th month after the close of your fiscal year.

If A taxpayer dies, the executor, administrator, or legal representative must file the final return for the decedent on or before the 15th day of the 4th month following the close of the deceased taxpayer's normal tax year.

If your principal place of abode for the tax year is outside the United States ( including Alaska and Hawaii ), Puerto Rico, or the Virgin Islands and you have no legal residence or principal place of business in any Internal Revenue district in the United States, you should file your return with the Office of International Operations, Internal Revenue Service, Washington 25, D.C..

If the plants are cared for and protected over the winter, the second year is more prolific than the first.

If a child with an I.Q. of 120 scored 5.5 in achievement, his discrepancy score would be, representing of one year of over-achievement.

If such a child scored 3.0, his discrepancy score would be -.5, representing of one year of under-achievement.

If you are not well acquainted with the area in which you wish to locate, or if you are not sure that you and your family will like and make a success of farming, usually you would do better to rent a place for a year or two before you buy.

If a red Bordeaux of a good name and year is bitter or acid, or cloying and muddy-tasting, leave it alone for a while.

If William wished to continue operations for a year, why not simply leave the Negroes undisturbed and pay them `` as high wages to remain there as are ever paid the labor of persons of their sex & age.

If Barnett doesn't call a special session in 1961, it will be the first year in the last decade that the Legislature has not met in regular or special session.

Primo Levi, who described his year in Auschwitz in If This Is a Man, wrote:

If the author wished, he could apply for a second 14 ‑ year monopoly grant, but after that the work entered the public domain, so it could be used and built upon by others.

If a 2, 000 ( lb / ac )/ year sequestration rate was achieved on all of cropland in the United States, nearly 1. 6 billion tons of carbon dioxide would be sequestered per year, mitigating close to one quarter of the country's total fossil fuel emissions.

If the Cimbri did in fact come from Jutland, evidence that the they practised ritualistic sacrifice may be found in the Haraldskær Woman discovered in Jutland in the year 1835.

In response to Lord Chalfont's claim in that the Soviet Union was giving the European peace movement £ 100 million a year, Bruce Kent said, " If they were, it was certainly not getting to our grotty little office in Finsbury Park.

If the chronicles deal with events year by year, they are often called annals.