2497:
747:
553:
1254:
1070:
In astronomy, stars are routinely treated as point sources even though they are much larger than the Earth. This is a good approximation because the distance from even a nearby star to the Earth is much larger than the star's diameter. For instance, the irradiance of
409:
319:
742:{\displaystyle E_{\mathrm {e} }={\frac {n}{2\mu _{0}\mathrm {c} }}E_{\mathrm {m} }^{2}\cos \alpha ={\frac {n\varepsilon _{0}\mathrm {c} }{2}}E_{\mathrm {m} }^{2}\cos \alpha \,or{\frac {n}{2Z_{0}}}E_{\mathrm {m} }^{2}\cos \alpha ,}
195:
500:
864:
1134:
1031:
2161:
per unit frequency or wavelength. The latter is commonly measured in W⋅m⋅nm. "Spectral emittance" is an old term for this quantity. This is sometimes also confusingly called "spectral intensity".
106:(W⋅m⋅Hz), while spectral irradiance of a wavelength spectrum is measured in watts per square metre per metre (W⋅m), or more commonly watts per square metre per nanometre (W⋅m⋅nm).
1067:
For quick approximations, this equation indicates that doubling the distance reduces irradiation to one quarter; or similarly, to double irradiation, reduce the distance to 71%.
908:
2119:
per unit area. This is the emitted component of radiosity. "Radiant emittance" is an old term for this quantity. This is sometimes also confusingly called "intensity".
344:
254:
136:
1274:
Average solar irradiance at the top of the Earth's atmosphere is roughly 1361 W/m, but at surface irradiance is approximately 1000 W/m on a clear day.
1121:, which is the component that is reflected from the ground. The average ground reflection is about 20% of the global irradiance. Hence, the irradiance
440:
547:, the Poynting vector always points to the direction of propagation while oscillating in magnitude. The irradiance of a surface is then given by
1895:
per unit frequency or wavelength. This is sometimes also confusingly called "spectral intensity". Non-SI units of spectral flux density include
2629:
58:
2042:
per unit frequency or wavelength. The latter is commonly measured in W⋅m⋅nm. This is sometimes also confusingly called "spectral intensity".
1306:
2712:
Liu, B. Y. H.; Jordan, R. C. (1960). "The interrelationship and characteristic distribution of direct, diffuse and total solar radiation".
966:
of light produces spherical wavefronts. The irradiance in this case varies inversely with the square of the distance from the source.
1466:
Radiant energy emitted, reflected, transmitted or received, per unit time. This is sometimes also called "radiant power", and called
1249:{\displaystyle E_{\mathrm {e} }=E_{\mathrm {e} ,\mathrm {dir} }+E_{\mathrm {e} ,\mathrm {diff} }+E_{\mathrm {e} ,\mathrm {refl} }.}
817:
2280:
per unit frequency or wavelength. The latter is commonly measured in J⋅m⋅nm. This is sometimes also called "spectral fluence".
972:
2592:
2667:
2621:
1299:
17:
95:
50:
2753:
1292:
1639:
Radiant intensity per unit frequency or wavelength. The latter is commonly measured in W⋅sr⋅nm. This is a
2690:
2562:
921:
911:
870:
404:{\displaystyle E_{\mathrm {e} ,\lambda }={\frac {\partial E_{\mathrm {e} }}{\partial \lambda }},}
102:
and units: spectral irradiance of a frequency spectrum is measured in watts per square metre per
2352:
2005:
1962:
1390:
2557:
1858:
947:
2721:
2359:
should be denoted with suffix "e" (for "energetic") to avoid confusion with photometric or
99:
1764:
per unit frequency or wavelength. The latter is commonly measured in W⋅sr⋅m⋅nm. This is a
1593:
Radiant flux emitted, reflected, transmitted or received, per unit solid angle. This is a
950:
of the propagation medium. This assumption is typically valid in transparent media in the
8:
2758:
2542:
2333:
1100:
The global irradiance on a horizontal surface on Earth consists of the direct irradiance
809:
796:
540:
314:{\displaystyle E_{\mathrm {e} ,\nu }={\frac {\partial E_{\mathrm {e} }}{\partial \nu }},}
127:
69:
2725:
1516:
Radiant flux per unit frequency or wavelength. The latter is commonly measured in W⋅nm.
2652:
2622:"Thermal insulation — Heat transfer by radiation — Physical quantities and definitions"
205:
2238:
integrated over time of irradiation. This is sometimes also called "radiant fluence".
2733:
2686:
2663:
2598:
2588:
2356:
1725:
1602:
1553:
525:
190:{\displaystyle E_{\mathrm {e} }={\frac {\partial \Phi _{\mathrm {e} }}{\partial A}},}
73:
2729:
2547:
2243:
2200:
2124:
2081:
1264:
1095:
1076:
1072:
951:
769:
230:
98:
is taken as a function of frequency or of wavelength. The two forms have different
72:, but this term is avoided in radiometry where such usage leads to confusion with
2531:
1908:
431:
1347:
779:
2496:
2747:
2659:
2602:
495:{\displaystyle E_{\mathrm {e} }=\langle |\mathbf {S} |\rangle \cos \alpha ,}
2441:, not to be confused with a letter "v", indicating a photometric quantity.)
1811:
1475:
1429:
1050:
963:
427:
39:
1768:
quantity. This is sometimes also confusingly called "spectral intensity".
2521:
2438:
2552:
2526:
2464:
2328:
1467:
1268:
1083:
544:
91:
31:
2000:
per unit area. This is sometimes also confusingly called "intensity".
1849:
per unit area. This is sometimes also confusingly called "intensity".
2428:
2377:
2375:
2373:
2371:
2369:
1575:
1569:
87:
65:
2536:
1682:
1260:
2366:
2658:(3. ed., reprint. with corr. ed.). Upper Saddle River, NJ :
2516:
1720:
quantity. This is sometimes also confusingly called "intensity".
426:
Irradiance of a surface is also, according to the definition of
2511:
2360:
1896:
783:
1712:
Radiant flux emitted, reflected, transmitted or received by a
1498:
1492:
1367:
1362:
103:
64:
per square centimetre per second (erg⋅cm⋅s) is often used in
1114:. On a tilted plane, there is another irradiance component,
859:{\textstyle c={\frac {1}{\sqrt {\varepsilon _{0}\mu _{0}}}}}
1447:
1442:
54:
2486:
2469:
2433:
1716:, per unit solid angle per unit projected area. This is a
1026:{\displaystyle E={\frac {P}{A}}={\frac {P}{4\pi r^{2}}},}
61:
331:
Spectral irradiance in wavelength of a surface, denoted
2691:"Technology fundamentals—The sun as an energy resource"
2323:
241:
Spectral irradiance in frequency of a surface, denoted
873:
820:
1137:
975:
556:
443:
347:
257:
139:
2500:
Comparison of photometric and radiometric quantities
2481:
2479:
2459:
2457:
2455:
2453:
2451:
2449:
2447:
430:, equal to the time-average of the component of the
2651:
1263:of solar irradiance over a time period is called "
1248:
1025:
902:
858:
741:
494:
403:
313:
189:
2476:
2444:
2745:
2485:Directional quantities are denoted with suffix "
2423:
2421:
2419:
2417:
2415:
2413:
2411:
1128:on a tilted plane consists of three components:
2616:
2614:
2612:
2234:per unit area, or equivalently irradiance of a
1786:watt per steradian per square metre, per metre
1745:watt per steradian per square metre per hertz
762:is the amplitude of the wave's electric field;
126:("e" for "energetic", to avoid confusion with
2408:
1300:
2681:
2679:
2609:
2346:
477:
459:
109:
27:Measure of radiant energy over surface area
2685:
1996:(emitted, reflected and transmitted by) a
1307:
1293:
1059:is the surface area of a sphere of radius
2711:
2676:
2649:
681:
2643:
2495:
86:is the irradiance of a surface per unit
76:. In astrophysics, irradiance is called
2582:
14:
2746:
2585:An introduction to modern astrophysics
1277:
236:
2242:
2123:
2004:
1853:
1724:
1601:
1474:
1385:Energy of electromagnetic radiation.
1327:
1324:
1321:
1318:
2381:Alternative symbols sometimes seen:
1697:watt per steradian per square metre
2463:Spectral quantities given per unit
2427:Spectral quantities given per unit
1089:
524:is the angle between a unit vector
24:
2583:Carroll, Bradley W. (2017-09-07).
2298:joule per square metre, per metre
1237:
1234:
1231:
1228:
1220:
1205:
1202:
1199:
1196:
1188:
1173:
1170:
1167:
1159:
1144:
1086:) is about 2.7 × 10 W/m on Earth.
716:
661:
645:
605:
592:
563:
450:
389:
381:
372:
354:
299:
291:
282:
264:
175:
167:
162:
158:
146:
25:
2770:
2539:(photosynthesis-irradiance curve)
2261:joule per square metre per hertz
2179:watt per square metre, per metre
2060:watt per square metre, per metre
1941:watt per square metre, per metre
119:Irradiance of a surface, denoted
2142:watt per square metre per hertz
2023:watt per square metre per hertz
1876:watt per square metre per hertz
1424:Radiant energy per unit volume.
468:
2654:Introduction to electrodynamics
957:
2705:
2576:
920:This formula assumes that the
473:
463:
434:perpendicular to the surface:
13:
1:
2569:
2230:Radiant energy received by a
1661:watt per steradian per metre
1620:watt per steradian per hertz
772:of the medium of propagation;
215:is the radiant flux received;
114:
68:. Irradiance is often called
2734:10.1016/0038-092X(60)90062-1
2650:Griffiths, David J. (1999).
903:{\textstyle Z_{0}=\mu _{0}c}
57:per square metre (W⋅m). The
7:
2504:
2355:recommend that radiometric
421:
130:quantities), is defined as
94:, depending on whether the
10:
2775:
1093:
2467:are denoted with suffix "
2431:are denoted with suffix "
2318:
2275:
2199:
2156:
2080:
2037:
1961:
1890:
1806:
1759:
1681:
1638:
1552:
1515:
1428:
1389:
1346:
1341:
1338:
1335:
1332:
924:is negligible; i.e. that
110:Mathematical definitions
2353:Standards organizations
2215:joule per square metre
1107:and diffuse irradiance
952:optical frequency range
922:magnetic susceptibility
912:impedance of free space
518:is the Poynting vector;
229:by a surface is called
2695:Renewable Energy World
2501:
2276:Radiant exposure of a
2157:Radiant exitance of a
2096:watt per square metre
1977:watt per square metre
1826:watt per square metre
1405:joule per cubic metre
1391:Radiant energy density
1250:
1027:
904:
860:
743:
496:
405:
315:
191:
2558:Spectral flux density
2499:
2405:for radiant exitance.
1859:Spectral flux density
1251:
1028:
948:magnetic permeability
905:
861:
744:
497:
406:
316:
192:
53:of irradiance is the
2563:Stefan–Boltzmann law
2389:for radiant energy,
1135:
973:
871:
818:
554:
512:is the time-average;
441:
345:
255:
137:
49:per unit area. The
2754:Physical quantities
2726:1960SoEn....4....1L
2543:Solar azimuth angle
1855:Spectral irradiance
1729:Specific intensity
1315:
1287:SI radiometry units
1278:SI radiometry units
1075:(radiant flux: 1.5
810:vacuum permittivity
797:vacuum permeability
726:
671:
615:
528:to the surface and
418:is the wavelength.
237:Spectral irradiance
84:Spectral irradiance
2687:Quaschning, Volker
2502:
2397:for radiant flux,
2006:Spectral radiosity
1603:Spectral intensity
1284:
1246:
1023:
900:
856:
739:
710:
655:
599:
541:linearly polarized
536:For a propagating
492:
401:
328:is the frequency.
311:
206:partial derivative
187:
2594:978-1-108-42216-1
2342:
2341:
2244:Spectral exposure
2125:Spectral exitance
1726:Spectral radiance
1554:Radiant intensity
1082:, distance: 4.34
1018:
990:
854:
853:
708:
653:
597:
396:
306:
225:The radiant flux
182:
74:radiant intensity
16:(Redirected from
2766:
2738:
2737:
2709:
2703:
2702:
2683:
2674:
2673:
2657:
2647:
2641:
2640:
2638:
2637:
2618:
2607:
2606:
2580:
2548:Solar irradiance
2490:
2483:
2474:
2461:
2442:
2437:" (Greek letter
2425:
2406:
2404:
2401:for irradiance,
2400:
2396:
2392:
2388:
2384:
2379:
2364:
2350:
2295:
2258:
2212:
2201:Radiant exposure
2176:
2139:
2093:
2082:Radiant exitance
2057:
2020:
1974:
1938:
1922:
1918:
1914:
1906:
1902:
1891:Irradiance of a
1873:
1823:
1783:
1742:
1694:
1658:
1617:
1565:
1529:
1488:
1439:
1402:
1359:
1316:
1309:
1302:
1295:
1288:
1283:
1255:
1253:
1252:
1247:
1242:
1241:
1240:
1223:
1210:
1209:
1208:
1191:
1178:
1177:
1176:
1162:
1149:
1148:
1147:
1096:Solar irradiance
1090:Solar irradiance
1073:Alpha Centauri A
1062:
1058:
1048:
1043:is the distance;
1042:
1032:
1030:
1029:
1024:
1019:
1017:
1016:
1015:
996:
991:
983:
946:is the relative
909:
907:
906:
901:
896:
895:
883:
882:
865:
863:
862:
857:
855:
852:
851:
842:
841:
832:
828:
770:refractive index
748:
746:
745:
740:
725:
720:
719:
709:
707:
706:
705:
689:
670:
665:
664:
654:
649:
648:
643:
642:
629:
614:
609:
608:
598:
596:
595:
590:
589:
573:
568:
567:
566:
543:electromagnetic
511:
501:
499:
498:
493:
476:
471:
466:
455:
454:
453:
410:
408:
407:
402:
397:
395:
387:
386:
385:
384:
370:
365:
364:
357:
338:, is defined as
320:
318:
317:
312:
307:
305:
297:
296:
295:
294:
280:
275:
274:
267:
248:, is defined as
231:radiant exitance
196:
194:
193:
188:
183:
181:
173:
172:
171:
170:
156:
151:
150:
149:
21:
2774:
2773:
2769:
2768:
2767:
2765:
2764:
2763:
2744:
2743:
2742:
2741:
2710:
2706:
2684:
2677:
2670:
2648:
2644:
2635:
2633:
2632:catalogue. 1989
2620:
2619:
2610:
2595:
2581:
2577:
2572:
2567:
2532:Light diffusion
2507:
2494:
2493:
2484:
2477:
2462:
2445:
2426:
2409:
2402:
2398:
2394:
2390:
2386:
2382:
2380:
2367:
2351:
2347:
2338:
2294:
2285:
2257:
2248:
2211:
2205:
2175:
2166:
2138:
2129:
2092:
2086:
2056:
2047:
2038:Radiosity of a
2019:
2010:
1973:
1967:
1937:
1928:
1920:
1916:
1912:
1909:solar flux unit
1904:
1900:
1872:
1863:
1857:
1822:
1816:
1810:
1782:
1773:
1741:
1732:
1728:
1693:
1687:
1657:
1648:
1616:
1607:
1564:
1558:
1532:watt per metre
1528:
1521:
1487:
1480:
1438:
1434:
1401:
1395:
1358:
1352:
1314:
1313:
1286:
1280:
1227:
1219:
1218:
1214:
1195:
1187:
1186:
1182:
1166:
1158:
1157:
1153:
1143:
1142:
1138:
1136:
1133:
1132:
1127:
1120:
1113:
1106:
1098:
1092:
1080:
1060:
1056:
1046:
1040:
1011:
1007:
1000:
995:
982:
974:
971:
970:
960:
945:
938:
930:
891:
887:
878:
874:
872:
869:
868:
847:
843:
837:
833:
827:
819:
816:
815:
807:
794:
761:
721:
715:
714:
701:
697:
693:
688:
666:
660:
659:
644:
638:
634:
630:
628:
610:
604:
603:
591:
585:
581:
577:
572:
562:
561:
557:
555:
552:
551:
509:
472:
467:
462:
449:
448:
444:
442:
439:
438:
432:Poynting vector
424:
388:
380:
379:
375:
371:
369:
353:
352:
348:
346:
343:
342:
337:
298:
290:
289:
285:
281:
279:
263:
262:
258:
256:
253:
252:
247:
239:
214:
174:
166:
165:
161:
157:
155:
145:
144:
140:
138:
135:
134:
125:
117:
112:
28:
23:
22:
15:
12:
11:
5:
2772:
2762:
2761:
2756:
2740:
2739:
2704:
2675:
2668:
2642:
2608:
2593:
2587:. p. 60.
2574:
2573:
2571:
2568:
2566:
2565:
2560:
2555:
2550:
2545:
2540:
2534:
2529:
2524:
2519:
2514:
2508:
2506:
2503:
2492:
2491:
2475:
2443:
2407:
2365:
2344:
2343:
2340:
2339:
2337:
2336:
2331:
2326:
2320:
2316:
2315:
2302:
2299:
2296:
2289:
2282:
2281:
2274:
2265:
2262:
2259:
2252:
2246:
2240:
2239:
2228:
2219:
2216:
2213:
2209:
2203:
2197:
2196:
2183:
2180:
2177:
2170:
2163:
2162:
2155:
2146:
2143:
2140:
2133:
2127:
2121:
2120:
2109:
2100:
2097:
2094:
2090:
2084:
2078:
2077:
2064:
2061:
2058:
2051:
2044:
2043:
2036:
2027:
2024:
2021:
2014:
2008:
2002:
2001:
1990:
1981:
1978:
1975:
1971:
1965:
1959:
1958:
1945:
1942:
1939:
1932:
1925:
1924:
1917:10 W⋅m⋅Hz
1905:10 W⋅m⋅Hz
1889:
1880:
1877:
1874:
1867:
1861:
1851:
1850:
1839:
1830:
1827:
1824:
1820:
1814:
1804:
1803:
1790:
1787:
1784:
1777:
1770:
1769:
1760:Radiance of a
1758:
1749:
1746:
1743:
1736:
1730:
1722:
1721:
1710:
1701:
1698:
1695:
1691:
1685:
1679:
1678:
1665:
1662:
1659:
1652:
1645:
1644:
1637:
1624:
1621:
1618:
1611:
1605:
1599:
1598:
1591:
1578:
1572:
1566:
1562:
1556:
1550:
1549:
1536:
1533:
1530:
1523:
1518:
1517:
1514:
1501:
1495:
1489:
1482:
1478:
1472:
1471:
1470:in Astronomy.
1464:
1451:
1445:
1440:
1436:
1432:
1426:
1425:
1422:
1409:
1406:
1403:
1399:
1393:
1387:
1386:
1383:
1370:
1365:
1360:
1356:
1350:
1348:Radiant energy
1344:
1343:
1340:
1337:
1334:
1330:
1329:
1326:
1323:
1320:
1312:
1311:
1304:
1297:
1289:
1285:
1279:
1276:
1265:solar exposure
1257:
1256:
1245:
1239:
1236:
1233:
1230:
1226:
1222:
1217:
1213:
1207:
1204:
1201:
1198:
1194:
1190:
1185:
1181:
1175:
1172:
1169:
1165:
1161:
1156:
1152:
1146:
1141:
1125:
1118:
1111:
1104:
1094:Main article:
1091:
1088:
1078:
1065:
1064:
1054:
1044:
1034:
1033:
1022:
1014:
1010:
1006:
1003:
999:
994:
989:
986:
981:
978:
959:
956:
943:
936:
928:
918:
917:
916:
915:
899:
894:
890:
886:
881:
877:
866:
850:
846:
840:
836:
831:
826:
823:
805:
801:
800:
792:
788:
787:
780:speed of light
773:
763:
759:
750:
749:
738:
735:
732:
729:
724:
718:
713:
704:
700:
696:
692:
687:
684:
680:
677:
674:
669:
663:
658:
652:
647:
641:
637:
633:
627:
624:
621:
618:
613:
607:
602:
594:
588:
584:
580:
576:
571:
565:
560:
534:
533:
519:
513:
503:
502:
491:
488:
485:
482:
479:
475:
470:
465:
461:
458:
452:
447:
423:
420:
412:
411:
400:
394:
391:
383:
378:
374:
368:
363:
360:
356:
351:
335:
322:
321:
310:
304:
301:
293:
288:
284:
278:
273:
270:
266:
261:
245:
238:
235:
223:
222:
216:
212:
209:
198:
197:
186:
180:
177:
169:
164:
160:
154:
148:
143:
123:
116:
113:
111:
108:
26:
18:Radiation flux
9:
6:
4:
3:
2:
2771:
2760:
2757:
2755:
2752:
2751:
2749:
2735:
2731:
2727:
2723:
2719:
2715:
2708:
2700:
2696:
2692:
2688:
2682:
2680:
2671:
2669:0-13-805326-X
2665:
2661:
2660:Prentice-Hall
2656:
2655:
2646:
2631:
2627:
2626:ISO 9288:1989
2623:
2617:
2615:
2613:
2604:
2600:
2596:
2590:
2586:
2579:
2575:
2564:
2561:
2559:
2556:
2554:
2551:
2549:
2546:
2544:
2541:
2538:
2535:
2533:
2530:
2528:
2525:
2523:
2520:
2518:
2515:
2513:
2510:
2509:
2498:
2488:
2482:
2480:
2472:
2471:
2466:
2460:
2458:
2456:
2454:
2452:
2450:
2448:
2440:
2436:
2435:
2430:
2424:
2422:
2420:
2418:
2416:
2414:
2412:
2378:
2376:
2374:
2372:
2370:
2362:
2358:
2354:
2349:
2345:
2335:
2332:
2330:
2327:
2325:
2322:
2321:
2317:
2314:
2310:
2306:
2303:
2300:
2297:
2293:
2288:
2284:
2283:
2279:
2273:
2269:
2266:
2263:
2260:
2256:
2251:
2247:
2245:
2241:
2237:
2233:
2229:
2227:
2223:
2220:
2217:
2214:
2208:
2204:
2202:
2198:
2195:
2191:
2187:
2184:
2181:
2178:
2174:
2169:
2165:
2164:
2160:
2154:
2150:
2147:
2144:
2141:
2137:
2132:
2128:
2126:
2122:
2118:
2114:
2111:Radiant flux
2110:
2108:
2104:
2101:
2098:
2095:
2089:
2085:
2083:
2079:
2076:
2072:
2068:
2065:
2062:
2059:
2055:
2050:
2046:
2045:
2041:
2035:
2031:
2028:
2025:
2022:
2018:
2013:
2009:
2007:
2003:
1999:
1995:
1992:Radiant flux
1991:
1989:
1985:
1982:
1979:
1976:
1970:
1966:
1964:
1960:
1957:
1953:
1949:
1946:
1943:
1940:
1936:
1931:
1927:
1926:
1910:
1898:
1894:
1888:
1884:
1881:
1878:
1875:
1871:
1866:
1862:
1860:
1856:
1852:
1848:
1844:
1841:Radiant flux
1840:
1838:
1834:
1831:
1828:
1825:
1819:
1815:
1813:
1809:
1805:
1802:
1798:
1794:
1791:
1788:
1785:
1781:
1776:
1772:
1771:
1767:
1763:
1757:
1753:
1750:
1747:
1744:
1740:
1735:
1731:
1727:
1723:
1719:
1715:
1711:
1709:
1705:
1702:
1699:
1696:
1690:
1686:
1684:
1680:
1677:
1673:
1669:
1666:
1663:
1660:
1656:
1651:
1647:
1646:
1642:
1636:
1632:
1628:
1625:
1622:
1619:
1615:
1610:
1606:
1604:
1600:
1596:
1592:
1590:
1586:
1582:
1579:
1577:
1573:
1571:
1567:
1561:
1557:
1555:
1551:
1548:
1544:
1540:
1537:
1534:
1531:
1527:
1520:
1519:
1513:
1509:
1505:
1502:
1500:
1496:
1494:
1490:
1486:
1479:
1477:
1476:Spectral flux
1473:
1469:
1465:
1463:
1459:
1455:
1452:
1449:
1446:
1444:
1441:
1433:
1431:
1427:
1423:
1421:
1417:
1413:
1410:
1407:
1404:
1398:
1394:
1392:
1388:
1384:
1382:
1378:
1374:
1371:
1369:
1366:
1364:
1361:
1355:
1351:
1349:
1345:
1331:
1317:
1310:
1305:
1303:
1298:
1296:
1291:
1290:
1282:
1275:
1272:
1270:
1266:
1262:
1243:
1224:
1215:
1211:
1192:
1183:
1179:
1163:
1154:
1150:
1139:
1131:
1130:
1129:
1124:
1117:
1110:
1103:
1097:
1087:
1085:
1081:
1074:
1068:
1055:
1052:
1045:
1039:
1038:
1037:
1020:
1012:
1008:
1004:
1001:
997:
992:
987:
984:
979:
976:
969:
968:
967:
965:
955:
953:
949:
942:
934:
927:
923:
913:
897:
892:
888:
884:
879:
875:
867:
848:
844:
838:
834:
829:
824:
821:
814:
813:
811:
803:
802:
798:
790:
789:
785:
781:
777:
774:
771:
767:
764:
758:
755:
754:
753:
736:
733:
730:
727:
722:
711:
702:
698:
694:
690:
685:
682:
678:
675:
672:
667:
656:
650:
639:
635:
631:
625:
622:
619:
616:
611:
600:
586:
582:
578:
574:
569:
558:
550:
549:
548:
546:
542:
539:
531:
527:
523:
520:
517:
514:
508:
507:
506:
489:
486:
483:
480:
456:
445:
437:
436:
435:
433:
429:
419:
417:
398:
392:
376:
366:
361:
358:
349:
341:
340:
339:
334:
329:
327:
308:
302:
286:
276:
271:
268:
259:
251:
250:
249:
244:
234:
232:
228:
220:
217:
210:
207:
203:
202:
201:
184:
178:
152:
141:
133:
132:
131:
129:
122:
107:
105:
101:
97:
93:
89:
85:
81:
79:
75:
71:
67:
63:
60:
56:
52:
48:
44:
41:
37:
33:
19:
2717:
2714:Solar Energy
2713:
2707:
2698:
2694:
2653:
2645:
2634:. Retrieved
2625:
2584:
2578:
2468:
2432:
2348:
2312:
2308:
2304:
2291:
2286:
2277:
2271:
2267:
2254:
2249:
2235:
2231:
2225:
2221:
2206:
2193:
2189:
2185:
2172:
2167:
2158:
2152:
2148:
2135:
2130:
2116:
2112:
2106:
2102:
2087:
2074:
2070:
2066:
2053:
2048:
2039:
2033:
2029:
2016:
2011:
1997:
1993:
1987:
1983:
1968:
1955:
1951:
1947:
1934:
1929:
1892:
1886:
1882:
1869:
1864:
1854:
1846:
1842:
1836:
1832:
1817:
1812:Flux density
1807:
1800:
1796:
1792:
1779:
1774:
1765:
1761:
1755:
1751:
1738:
1733:
1717:
1713:
1707:
1703:
1688:
1675:
1671:
1667:
1654:
1649:
1640:
1634:
1630:
1626:
1613:
1608:
1594:
1588:
1584:
1580:
1559:
1546:
1542:
1538:
1525:
1511:
1507:
1503:
1484:
1461:
1457:
1453:
1430:Radiant flux
1419:
1415:
1411:
1396:
1380:
1376:
1372:
1353:
1281:
1273:
1258:
1122:
1115:
1108:
1101:
1099:
1069:
1066:
1051:radiant flux
1035:
964:point source
961:
958:Point source
940:
932:
925:
919:
775:
765:
756:
751:
537:
535:
529:
521:
515:
504:
428:radiant flux
425:
415:
413:
332:
330:
325:
323:
242:
240:
226:
224:
221:is the area.
218:
199:
120:
118:
83:
82:
78:radiant flux
77:
46:
42:
40:radiant flux
35:
29:
2701:(5): 90–93.
2522:Illuminance
2363:quantities.
1766:directional
1718:directional
1641:directional
1595:directional
128:photometric
2759:Radiometry
2748:Categories
2636:2015-03-15
2570:References
2553:Solar noon
2527:Insolation
2465:wavelength
2357:quantities
2334:Photometry
2329:Radiometry
2319:See also:
1921:10 Jy
1913:1 sfu
1808:Irradiance
1748:W⋅sr⋅m⋅Hz
1643:quantity.
1597:quantity.
1468:luminosity
1325:Dimension
1269:insolation
545:plane wave
538:sinusoidal
115:Irradiance
100:dimensions
92:wavelength
36:irradiance
32:radiometry
2603:991641816
2429:frequency
1963:Radiosity
1901:1 Jy
1570:steradian
1568:watt per
1491:watt per
1319:Quantity
1005:π
889:μ
845:μ
835:ε
734:α
731:
679:α
676:
636:ε
623:α
620:
583:μ
487:α
484:
478:⟩
460:⟨
393:λ
390:∂
373:∂
362:λ
303:ν
300:∂
283:∂
272:ν
204:∂ is the
176:∂
163:Φ
159:∂
88:frequency
70:intensity
66:astronomy
2720:(3): 1.
2689:(2003).
2537:PI curve
2505:See also
1843:received
1683:Radiance
1623:W⋅sr⋅Hz
1261:integral
939:) where
422:Property
96:spectrum
59:CGS unit
43:received
2722:Bibcode
2517:Fluence
2278:surface
2264:J⋅m⋅Hz
2236:surface
2232:surface
2159:surface
2145:W⋅m⋅Hz
2117:surface
2113:emitted
2040:surface
2026:W⋅m⋅Hz
1998:surface
1994:leaving
1893:surface
1879:W⋅m⋅Hz
1847:surface
1789:W⋅sr⋅m
1762:surface
1714:surface
1700:W⋅sr⋅m
1664:W⋅sr⋅m
1342:Symbol
1336:Symbol
1049:is the
910:is the
808:is the
795:is the
778:is the
768:is the
227:emitted
208:symbol;
51:SI unit
47:surface
38:is the
2666:
2601:
2591:
2512:Albedo
2361:photon
1907:) and
1897:jansky
1450:= J/s
1328:Notes
1267:" or "
1119:e,refl
1112:e,diff
1036:where
784:vacuum
752:where
526:normal
505:where
414:where
324:where
200:where
2115:by a
1845:by a
1493:hertz
1363:joule
1339:Name
1333:Name
1322:Unit
1105:e,dir
931:≈ 1 (
510:⟨ • ⟩
104:hertz
45:by a
2664:ISBN
2599:OCLC
2589:ISBN
2301:J/m
2218:J/m
2182:W/m
2099:W/m
2063:W/m
1980:W/m
1944:W/m
1829:W/m
1778:e,Ω,
1737:e,Ω,
1653:e,Ω,
1612:e,Ω,
1535:W/m
1443:watt
1408:J/m
1259:The
55:watt
2730:doi
2630:ISO
2393:or
2385:or
1923:).
1692:e,Ω
1563:e,Ω
1271:".
935:≈ μ
782:in
728:cos
673:cos
617:cos
481:cos
336:e,λ
246:e,ν
90:or
62:erg
30:In
2750::
2728:.
2716:.
2697:.
2693:.
2678:^
2662:.
2628:.
2624:.
2611:^
2597:.
2489:".
2478:^
2473:".
2446:^
2439:nu
2410:^
2368:^
2324:SI
2290:e,
2253:e,
2171:e,
2134:e,
2052:e,
2015:e,
1933:e,
1919:=
1915:=
1903:=
1868:e,
1576:sr
1574:W/
1524:e,
1499:Hz
1497:W/
1483:e,
1084:ly
962:A
954:.
812:;
233:.
80:.
34:,
2736:.
2732::
2724::
2718:4
2699:6
2672:.
2639:.
2605:.
2487:Ω
2470:λ
2434:ν
2403:W
2399:I
2395:F
2391:P
2387:E
2383:W
2313:T
2311:⋅
2309:L
2307:⋅
2305:M
2292:λ
2287:H
2272:T
2270:⋅
2268:M
2255:ν
2250:H
2226:T
2224:⋅
2222:M
2210:e
2207:H
2194:T
2192:⋅
2190:L
2188:⋅
2186:M
2173:λ
2168:M
2153:T
2151:⋅
2149:M
2136:ν
2131:M
2107:T
2105:⋅
2103:M
2091:e
2088:M
2075:T
2073:⋅
2071:L
2069:⋅
2067:M
2054:λ
2049:J
2034:T
2032:⋅
2030:M
2017:ν
2012:J
1988:T
1986:⋅
1984:M
1972:e
1969:J
1956:T
1954:⋅
1952:L
1950:⋅
1948:M
1935:λ
1930:E
1911:(
1899:(
1887:T
1885:⋅
1883:M
1870:ν
1865:E
1837:T
1835:⋅
1833:M
1821:e
1818:E
1801:T
1799:⋅
1797:L
1795:⋅
1793:M
1780:λ
1775:L
1756:T
1754:⋅
1752:M
1739:ν
1734:L
1708:T
1706:⋅
1704:M
1689:L
1676:T
1674:⋅
1672:L
1670:⋅
1668:M
1655:λ
1650:I
1635:T
1633:⋅
1631:L
1629:⋅
1627:M
1614:ν
1609:I
1589:T
1587:⋅
1585:L
1583:⋅
1581:M
1560:I
1547:T
1545:⋅
1543:L
1541:⋅
1539:M
1526:λ
1522:Φ
1512:T
1510:⋅
1508:L
1506:⋅
1504:M
1485:ν
1481:Φ
1462:T
1460:⋅
1458:L
1456:⋅
1454:M
1448:W
1437:e
1435:Φ
1420:T
1418:⋅
1416:L
1414:⋅
1412:M
1400:e
1397:w
1381:T
1379:⋅
1377:L
1375:⋅
1373:M
1368:J
1357:e
1354:Q
1308:e
1301:t
1294:v
1244:.
1238:l
1235:f
1232:e
1229:r
1225:,
1221:e
1216:E
1212:+
1206:f
1203:f
1200:i
1197:d
1193:,
1189:e
1184:E
1180:+
1174:r
1171:i
1168:d
1164:,
1160:e
1155:E
1151:=
1145:e
1140:E
1126:e
1123:E
1116:E
1109:E
1102:E
1079:☉
1077:L
1063:.
1061:r
1057:A
1053:;
1047:P
1041:r
1021:,
1013:2
1009:r
1002:4
998:P
993:=
988:A
985:P
980:=
977:E
944:r
941:μ
937:0
933:μ
929:r
926:μ
914:.
898:c
893:0
885:=
880:0
876:Z
849:0
839:0
830:1
825:=
822:c
806:0
804:ε
799:;
793:0
791:μ
786:;
776:c
766:n
760:m
757:E
737:,
723:2
717:m
712:E
703:0
699:Z
695:2
691:n
686:r
683:o
668:2
662:m
657:E
651:2
646:c
640:0
632:n
626:=
612:2
606:m
601:E
593:c
587:0
579:2
575:n
570:=
564:e
559:E
532:.
530:S
522:α
516:S
490:,
474:|
469:S
464:|
457:=
451:e
446:E
416:λ
399:,
382:e
377:E
367:=
359:,
355:e
350:E
333:E
326:ν
309:,
292:e
287:E
277:=
269:,
265:e
260:E
243:E
219:A
213:e
211:Φ
185:,
179:A
168:e
153:=
147:e
142:E
124:e
121:E
20:)
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