Meta tags:

Headings (most frequently used words):

background, of, cmb, dirbe, infrared, cosmic, explorer, contents, mission, history, spacecraft, scientific, findings, popular, culture, see, also, references, sources, further, reading, external, links, instruments, black, body, curve, intrinsic, anisotropy, detecting, early, galaxies, cosmological, implications, differential, microwave, radiometers, dmr, diffuse, experiment, far, absolute, spectrophotometer, firas,

Text of the page (most frequently used words):
the (348), and (115), from (71), since (71), kosmos (68), cobe (64), space (59), background (51), nasa (44), cosmic (38), this (31), was (29), #microwave (29), #infrared (28), universe (28), explorer (27), spacecraft (27), for (27), that (26), with (24), mission (24), cmb (23), edit (23), radiation (22), earth (21), telescope (20), solar (19), dirbe (18), were (18), satellite (17), launch (17), 2013 (17), 2021 (16), 1989 (16), 2015 (16), data (16), experiment (16), firas (16), program (15), are (15), usa (15), 2006 (15), missions (15), astro (15), instruments (15), retrieved (14), history (14), anisotropy (14), astronomical (14), diffuse (14), two (14), november (13), american (13), 1993 (13), 1992 (13), formation (13), has (13), galaxies (13), original (13), archived (13), other (12), october (12), 2024 (12), apollo (12), observatory (12), center (12), also (12), instrument (12), 2023 (11), 1996 (11), new (11), oso (11), cosmological (11), imp (11), article (11), issn (11), doi (11), bibcode (11), dust (11), which (11), dmr (11), would (11), axis (11), 2022 (10), 2017 (10), 2001 (10), 1995 (10), timeline (10), wmap (10), sky (10), published (10), 0004 (10), society (10), far (10), august (9), 2019 (9), 2018 (9), april (9), 2010 (9), 2009 (9), lunar (9), hubble (9), planck (9), iras (9), mather (9), big (9), bang (9), 637x (9), 1086 (9), astrophysical (9), journal (9), differential (9), made (9), sun (9), between (9), black (9), spin (9), wikipedia (8), text (8), source (8), july (8), 2008 (8), 2004 (8), 1998 (8), 1990 (8), system (8), shuttle (8), flight (8), ray (8), star (8), probe (8), john (8), goddard (8), structure (8), smoot (8), spectrum (8), orbit (8), results (8), body (8), used (8), view (7), january (7), control (7), 2025 (7), june (7), 2020 (7), 2003 (7), 1999 (7), 1987 (7), astronomy (7), mars (7), orbiter (7), ariel (7), observations (7), dark (7), university (7), map (7), galactic (7), public (7), domain (7), incorporates (7), wilkinson (7), absolute (7), spectrophotometer (7), 100 (7), temperature (7), each (7), measurements (7), their (7), may (6), page (6), 2026 (6), scientific (6), delta (6), explorers (6), sts (6), 2027 (6), 2005 (6), march (6), 2002 (6), 2000 (6), 1997 (6), 1994 (6), 1991 (6), facility (6), network (6), future (6), rover (6), science (6), list (6), 1979 (6), 1981 (6), cosmology (6), large (6), scale (6), galaxy (6), model (6), energy (6), class (6), physics (6), its (6), disk (6), angular (6), following (6), there (6), rate (6), helium (6), able (6), well (6), these (6), dewar (6), three (6), radiometer (6), search (5), use (5), sidebar (5), launched (5), telescopes (5), international (5), december (5), resurs (5), 2016 (5), 2012 (5), 2011 (5), astronaut (5), day (5), moon (5), small (5), deep (5), year (5), near (5), swift (5), discovery (5), exploration (5), 1973 (5), 1983 (5), sas (5), 1974 (5), scientists (5), main (5), shape (5), very (5), cold (5), george (5), detected (5), density (5), early (5), hauser (5), kelsall (5), moseley (5), silverberg (5), implications (5), radiometers (5), design (5), out (5), create (5), not (5), over (5), curve (5), uses (5), need (5), toggle (4), contents (4), about (4), policy (4), commons (4), last (4), category (4), orbiting (4), national (4), progress (4), molniya (4), galileo (4), pion (4), orbital (4), astronauts (4), one (4), related (4), voyager (4), pioneer (4), nancy (4), roman (4), james (4), sdo (4), observed (4), mercury (4), past (4), current (4), project (4), vehicle (4), deputy (4), group (4), time (4), hete (4), oao (4), spektr (4), 1972 (4), soho (4), david (4), director (4), portal (4), boomerang (4), expansion (4), nucleosynthesis (4), theory (4), epe (4), dipole (4), external (4), links (4), york (4), isbn (4), light (4), further (4), sources (4), survey (4), see (4), bands (4), bennett (4), nobel (4), prize (4), into (4), provide (4), than (4), regions (4), 140 (4), can (4), mass (4), ipd (4), findings (4), cooled (4), field (4), have (4), ghz (4), scan (4), anisotropies (4), flux (4), required (4), 300 (4), micrometres (4), altitude (4), hide (4), move (4), using (3), wikimedia (3), september (3), wikidata (3), all (3), articles (3), english (3), 2014 (3), short (3), description (3), different (3), california (3), satellites (3), experiments (3), separated (3), same (3), gorizont (3), 2035 (3), 2033 (3), 2032 (3), 2028 (3), 2007 (3), february (3), 1988 (3), fame (3), reading (3), picture (3), gemini (3), blue (3), operations (3), grace (3), webb (3), tess (3), reconnaissance (3), insight (3), opportunity (3), kepler (3), galex (3), robotic (3), commercial (3), services (3), surveyor (3), programs (3), orion (3), constellation (3), johnson (3), 1986 (3), 1958 (3), documentary (3), 1976 (3), 1985 (3), 1975 (3), 1980 (3), rxte (3), relikt (3), heao (3), 1982 (3), einstein (3), gamma (3), imager (3), astrosat (3), planned (3), stereo (3), radio (3), robert (3), special (3), balloon (3), gsfc (3), 2df (3), lambda (3), matter (3), components (3), redshift (3), friedmann (3), theories (3), indicates (3), proposals (3), fast (3), solrad (3), array (3), william (3), first (3), back (3), s2cid (3), 500 (3), arxiv (3), andrew (3), thomas (3), young (3), sheldon (3), dwek (3), wright (3), shafer (3), weiland (3), color (3), boggess (3), 420 (3), measurement (3), melchiorri (3), fluctuations (3), years (3), 089a (3), led (3), principal (3), been (3), significant (3), important (3), help (3), ebl (3), stars (3), extremely (3), integrated (3), during (3), only (3), cloud (3), seen (3), but (3), due (3), second (3), particles (3), wavelengths (3), keep (3), full (3), measuring (3), against (3), period (3), they (3), perfect (3), fit (3), berkeley (3), distribution (3), finding (3), measure (3), proposal (3), points (3), wavelength (3), along (3), horn (3), entire (3), systematic (3), weighs (3), watts (3), bit (3), sensitivity (3), high (3), shield (3), based (3), interference (3), provided (3), thermal (3), months (3), 560 (3), 900 (3), synchronous (3), momentum (3), iii (3), committee (3), tools (3), languages (2), table (2), mobile (2), conduct (2), contact (2), privacy (2), under (2), terms (2), site (2), attribution (2), utc (2), categories (2), link (2), pages (2), probes (2), rockets (2), united (2), states (2), launches (2), payloads (2), names (2), flights (2), gran (2), granat (2), kvant (2), intelsat (2), meteor (2), soyuz (2), 2037 (2), 2036 (2), hipparcos (2), sat (2), 2031 (2), 2030 (2), magellan (2), tdrs (2), sample (2), images (2), plaques (2), fields (2), world (2), family (2), portrait (2), creation (2), aircraft (2), navigation (2), apex (2), laboratory (2), themis (2), chandra (2), station (2), horizons (2), operating (2), rhessi (2), dawn (2), spitzer (2), artemis (2), human (2), great (2), observatories (2), observing (2), mariner (2), hitchhiker (2), spaceflight (2), building (2), complex (2), research (2), chief (2), administrator (2), general (2), augustine (2), initiative (2), proposed (2), jasmine (2), gems (2), finesse (2), cancelled (2), hitomi (2), wire (2), cxbn (2), corsa (2), 1970 (2), lost (2), trace (2), wise (2), uhuru (2), swas (2), suzaku (2), sampex (2), 1971 (2), copernicus (2), minxss (2), lisa (2), 1978 (2), iue (2), integral (2), ilo (2), fuse (2), euve (2), compton (2), cgro (2), chipsat (2), hut (2), 1964 (2), 1962 (2), worlds (2), euso (2), maxi (2), excede (2), arcus (2), litebird (2), prima (2), uvex (2), cosi (2), ibex (2), dampe (2), calet (2), ace (2), newton (2), xrism (2), nustar (2), nicer (2), ixpe (2), proba (2), iris (2), hinode (2), ultraviolet (2), optical (2), spherex (2), queqiao (2), notable (2), engineers (2), technology (2), test (2), institute (2), studies (2), sdss (2), reionization (2), quasar (2), filament (2), cdm (2), ultimate (2), fate (2), expanding (2), law (2), equations (2), flrw (2), metric (2), inflation (2), gravitational (2), wave (2), neutrino (2), principle (2), chronology (2), age (2), yet (2), titles (2), 103 (2), 105 (2), 106 (2), medium (2), cce (2), dade (2), rae (2), injun (2), geos (2), lspe (2), ground (2), spider (2), sunyaev (2), zeldovich (2), effect (2), website (2), oclc (2), lccn (2), true (2), story (2), 1998apj (2), 231 (2), press (2), fixsen (2), odegard (2), 508 (2), freudenreich (2), 485 (2), 468 (2), michael (2), 442 (2), interplanetary (2), 1994apj (2), 428 (2), characteristics (2), gov (2), cheng (2), meyer (2), weiss (2), measured (2), matsumoto (2), toshio (2), hiroshi (2), lange (2), richards (2), 941 (2), francesco (2), intermediate (2), 397 (2), after (2), times (2), how (2), primordial (2), seeds (2), product (2), references (2), mapping (2), called (2), save (2), popular (2), culture (2), follow (2), investigator (2), constraints (2), various (2), excess (2), must (2), detect (2), intensity (2), consistent (2), released (2), total (2), throughout (2), more (2), analysis (2), detailed (2), direct (2), emissions (2), had (2), found (2), previously (2), million (2), zodiacal (2), edge (2), our (2), position (2), according (2), then (2), lengths (2), kpc (2), top (2), origin (2), collected (2), smooth (2), region (2), information (2), vcd (2), when (2), taken (2), associated (2), gas (2), low (2), detecting (2), four (2), operation (2), frequencies (2), faint (2), part (2), contrast (2), today (2), clusters (2), intrinsic (2), spectral (2), difference (2), patch (2), internal (2), interferometer (2), long (2), slow (2), month (2), developments (2), showed (2), nagoya (2), announcement (2), brightness (2), rocket (2), teams (2), announced (2), detection (2), florence (2), level (2), later (2), unable (2), error (2), coverage (2), formed (2), cryogenically (2), spectrometer (2), measures (2), precision (2), range (2), collector (2), precise (2), input (2), reference (2), errors (2), ability (2), blackbody (2), investigate (2), off (2), detectors (2), micrometre (2), channels (2), 120 (2), cryostat (2), pair (2), antennas (2), achieved (2), duration (2), gal (2), possible (2), stray (2), maintain (2), stability (2), inclination (2), chosen (2), either (2), order (2), wheels (2), emission (2), until (2), evidence (2), cosmos (2), vandenberg (2), costs (2), work (2), received (2), 5920 (2), operated (2), type (2), appearance (2), upload (2), file (2), changes (2), read (2), subsection (2), log (2), account (2), donate (2), menu (2), add, topic, cookie, statement, statistics, developers, code, legal, safety, contacts, disclaimers, available, additional, apply, you, agree, registered, trademark, non, profit, organization, foundation, inc, creative, sharealike, license, rendered, parsoid, edited, hidden, child, parameter, dmy, dates, written, https, org, index, php, title, cosmic_background_explorer, oldid, 1373398148, yale, lux, israel, viaf, authority, databases, dots, commas, multiple, slashes, underlined, failures, marked, sign, deployed, enclosed, parentheses, crewed, 2054, 2053, 36l, 2052, 2051, 2050, 2049, 2048, 2047, 31l, magion, interkosmos, 2046, 2045, 2044, 2043, 2042, 2041, 2040, 2039, 2038, himawari, thor, 2034, olympus, 27l, 2029, nadezhda, 403, globus, okean, dfs, kopernikus, superbird, foton, 33l, tele, meteosat, jcsat, akebono, 29l, nikon, apps, challenge, exoplanet, archive, primates, tree, mice, stamps, hall, stolen, missing, rocks, displays, monument, mirror, memorial, module, postal, covers, incident, genesis, step, choose, anniversary, patches, medallions, insignia, goodwill, messages, golden, record, fallen, earthset, hello, smiled, mystic, mountain, pillars, pale, dot, marble, earthrise, artwork, cameras, cancellations, uncrewed, crews, name, lists, atomic, clock, canberra, madrid, goldstone, communications, veritas, davinci, nisar, europa, clipper, pace, perseverance, osiris, mms, juno, curiosity, odyssey, currently, helicopter, ingenuity, maven, cassini, aquarius, messenger, ladee, spirit, sojourner, grail, atlas, individual, featured, simplex, payload, terrestrial, frontiers, precursor, living, prometheus, viking, ranger, planetary, observer, millennium, mesur, mark, crew, transportation, roscosmos, mir, soviet, skylab, suborbital, directorate, checkout, 39b, 39a, assembly, kennedy, manned, social, spinoff, technologies, budget, ranks, positions, corps, scientist, race, aldridge, vision, caib, cfusai, ride, rogers, paine, task, aeronautics, act, 1915, naca, unknown, machine, planetariums, heliophysics, xipe, xeus, tpf, tauvex, sport, spica, snap, sim, simlite, sentinel, nano, lord, loft, jdem, ixo, hop, eddington, echo, destiny, darwin, aoso, aelita, tsubame, abrixas, 1965, 1966, failed, yokoh, 1959, vanguard, tenma, taiyo, srats, eii, solwind, rosat, hessi, 1984, picsat, pamela, odin, 1968, mikhailo, lomonosov, msx, most, max, valier, pathfinder, legri, kristall, ixae, iso, irts, obs, hisaki, sprint, hinotori, herschel, 1977, halca, muses, hakucho, ginga, gap, gaia, exosat, 1961, epoxi, epoch, dxs, cos, corot, bepposax, ans, astron, bbxrt, asca, atm, asteria, 1967, 1969, alouette, alexis, akari, agile, retired, theseus, theia, phoenix, origins, orbis, nro, donation, neomir, nautilus, lynx, life, luvoir, luci, jem, iwf, hypertelescope, habitable, habex, focal, fresnel, athena, taiji, quvik, plato, neo, cubespec, xuntian, mini, iss, cream, ams, particle, unclassified, xmm, xposat, leia, svom, gecam, fermi, hxmt, axaf, petrel, carruthers, geocorona, aso, aditya, neossat, hirise, hayabusa2, euclid, dscovr, cheops, chase, brite, aoi, wind, ncle, lissette, martinez, marc, kuchner, hansen, orlando, figueroa, gene, carl, feldman, fred, espenak, bindschadler, louis, band, rubilotta, associate, christyl, investments, anne, kinney, dennis, andrucyk, leadership, people, jwst, dynamics, lro, rossi, timing, heliospheric, hst, tracking, relay, getaway, landsat, fabrication, katherine, independent, verification, validation, magnetic, columbia, csbf, giss, facilities, observational, illustris, 6df, quintessence, fluid, accelerating, present, religious, interpretations, copernican, cosmogony, distance, ladder, observable, symbol, failure, route, before, intended, returned, indicate, italics, grey, active, green, ohmic, escape, astre, case, sunrise, ezie, awe, gusto, gold, twins, cindi, terriers, snoe, 107, tracers, 101, punch, aim, helioswarm, muse, 102, icon, image, sme, magsat, sage, ice, hcmm, isee, hawkeye, mts, sss, dme, 55c, 66a, 55b, 55a, 45a, 56a, 46a, tenerife, sza, south, pole, simons, saskatoon, quijote, quiet, qubic, quad, polarbear, ovro, strip, keck, groundbird, dasi, cosmosomas, capmap, bima, bicep, atca, amiba, arcminute, microkelvin, atacama, acbar, abs, tophat, qmap, maxima, ebex, swipe, arcade, archeops, thomson, scattering, sachs, wolfe, recombination, diffusion, damping, spot, variance, effects, scholarpedia, showing, 600, motion, relative, apod, profile, informational, video, prior, media, davidson, keay, 1400708m, 28215032, 93008500, 688, 12330, morrow, wrinkles, boslough, basicbooks, 465, 01575, inside, journey, odenwald, sten, newmark, jeffrey, 568, 18799050, 305737, 554o, 9610238, 554, study, liddle, lyth, perturbation, 119084975, 1016, 0370, 1573, 90114, 1993phr, 9303019, elsevier, reports, arny, 3rd, dubuque, iowa, mcgraw, hill, 978, 241593, explorations, introduction, youtube, saves, crash, release, esa, hfi, completes, christopher, magazine, arendt, leisawitz, pei, 122, 14706133, 306382, 106d, 9806129, 920, 304478, 1997apj, 920f, erratum, 678, 177724, 1996apj, 663f, 663, spiesman, lisse, carey, harvey, reach, stemwedel, sally, janet, 662, 175470, 1995apj, 662s, sodroski, franz, 646, 174274, 638s, 638, interstellar, dick, steven, voyages, beginning, cottingham, eplee, isaacman, noerdlinger, 449, 173575, 445f, 445, hayakawa, satio, matsuo, murakami, sato, shinji, 948, 6264, 1093, pasj, 1987pasj, 941h, publications, japan, implication, submillimeter, bianca, olivo, ceccarelli, cecilia, pietranera, luca, 183662, 1981apj, 250l, 250, scales, gulkis, janssen, murdock, 429, 171797, 1992apj, 420b, performance, wilford, noble, 0362, 4331, report, profound, began, schewe, phillip, stein, ben, vol, aip, bulletin, news, picks, leverington, 7750568m, 44174182, 00041456, 521, 65833, cambridge, display, royal, swedish, academy, sciences, trajectory, crouse, megan, development, week, s150, named, minor, planet, 9997, appeared, twice, season, episode, where, daydreams, helping, crashing, lee, cooper, gluons, guacamole, purple, clarified, expanded, upon, accomplishments, european, agency, continued, increase, resolution, mapped, charles, calculate, histories, observation, require, redshifts, larger, inferred, factor, stellar, mainly, generated, massive, undetected, enshrouded, dusty, forming, exact, cannot, unambiguously, resolved, looking, 5000, constitutes, metals, attributed, nuclear, implies, baryonic, implied, processed, heavier, elements, addition, section, numerous, questions, left, unanswered, metal, production, conversion, starlight, extragalactic, subtracted, centered, thought, place, few, kilometers, away, gravitation, influence, jupiter, saturn, contribution, above, midplane, radial, vertical, 333, respectively, warped, way, layer, indication, thick, contributions, determine, asteroid, cometary, conclude, grains, populate, asteroidal, emitting, surveyed, nine, candidates, weak, 240, derived, joined, luminosity, arises, cirrus, clouds, molecular, less, warm, extended, spiral, spend, detectable, dependent, supply, maps, subtracting, 000, compared, average, remnant, imprint, ripples, believed, produced, vast, devoid, obtained, subtraction, covered, speeds, modes, ten, serving, backdrop, eagerly, awaited, startling, theoretical, japanese, team, paul, 028, sounding, astronomers, simultaneously, borne, particular, claimed, agreement, however, number, attempted, duplicate, microkelvins, quadrupole, princeton, comparison, predicted, bars, smaller, width, red, crosses, merely, locate, fulfill, objectives, making, outside, initial, scope, conducted, overlapped, providing, consistency, check, overlap, assistance, discriminating, signals, polarizing, device, 1000, peak, flared, trumpet, having, sidelobe, levels, calibrator, covering, beam, regulation, calibration, compare, feature, provides, immunity, contributes, significantly, deviations, 1200, 130, 067, fourier, transform, michelson, consists, multiband, pointed, filters, longest, channel, baffled, gregorian, imaging, approximately, 1700, bolometers, photoconductors, investigation, distributed, around, outer, surface, employs, viewing, frequency, dual, polarization, improved, reliability, receiver, whose, switched, rapidly, obtaining, diameter, located, apart, stabilization, integrate, 114, 260, engineering, concluded, transferred, wff, wallops, parts, pertaining, superfluid, designed, vent, communication, arrays, conical, protected, transmitting, antenna, multilayer, insulating, blankets, isolation, 170, 650, combined, continually, below, plane, allowing, every, six, prove, determined, specifics, overriding, considerations, eliminate, circular, satisfied, requirements, within, capabilities, auxiliary, propulsion, good, compromise, charged, higher, altitudes, ascending, node, allow, boundary, sunlight, darkness, belts, meet, twin, demands, rotation, attitude, sophisticated, yaw, employed, oriented, carry, opposite, zero, net, elongation, angles, subsequent, modeling, rotate, tilted, velocity, vector, precaution, deposits, residual, atmospheric, optics, glow, result, neutral, hitting, surfaces, speed, rpm, rigorous, operate, minimum, constrain, amount, radiative, gain, cleanliness, reduce, entry, particulates, borrowed, heavily, some, unique, diagram, subject, cosmologists, wilson, tolman, suntzeff, schmidt, rubin, penzias, penrose, lemaître, huygens, hawking, guth, gamow, ellis, ehlers, dicke, sitter, alpher, alfvén, aaronson, sloan, digital, hole, bhi, baryons, photons, cnb, gwb, backgrounds, baryogenesis, physical, series, jointly, awarded, form, cmbe, template, ran, front, explaining, revealing, initially, evolved, panorama, gigantic, washington, aps, meeting, originally, delayed, plan, shuttles, grounded, prevented, going, companies, eventually, redesigned, placed, aboard, challenger, explosion, air, force, base, accepted, kept, excluding, launcher, cost, overruns, constructing, did, begin

Text of the page (random words):
december 1993 orbital parameters reference system geocentric orbit 3 regime sun synchronous orbit perigee altitude 900 km 560 mi apogee altitude 900 km 560 mi inclination 99 00 period 103 00 minutes instruments differential microwave radiometer dmr diffuse infrared background experiment dirbe far infrared absolute spectrophotometer firas cosmic background explorer mission patch explorer program ampte cce explorer 65 extreme ultraviolet explorer explorer 67 the cosmic background explorer cobe ˈ k oʊ b i koh bee also referred to as explorer 66 was a nasa satellite dedicated to cosmology which operated from 1989 to 1993 its goals were to investigate the cosmic microwave background radiation cmb or cmbr of the universe and provide measurements that would help shape the understanding of the cosmos cobe s measurements provided two key pieces of evidence that supported the big bang theory of the universe that the cmb has a near perfect black body spectrum and that it has very faint anisotropies two of cobe s principal investigators george f smoot iii and john c mather received the nobel prize in physics in 2006 for their work on the project according to the nobel prize committee the cobe project can also be regarded as the starting point for cosmology as a precision science 4 cobe was the second cosmic microwave background satellite following relikt 1 and was followed by two more advanced spacecraft the wilkinson microwave anisotropy probe wmap operated from 2001 to 2010 and the planck spacecraft from 2009 to 2013 mission edit the purpose of the cosmic background explorer cobe mission was to take precise measurements of the diffuse radiation between 1 micrometre and 1 cm 0 39 in over the whole celestial sphere the following quantities were measured 1 the spectrum of the 3 k radiation over the range 100 micrometres to 1 cm 0 39 in 2 the anisotropy of this radiation from 3 to 10 mm 0 39 in and 3 the spectrum and angular distribution of diffuse infrared background radiation at wavelengths from 1 to 300 micrometres 5 history edit in 1974 nasa issued an announcement of opportunity for astronomical missions that would use a small or medium sized explorer spacecraft out of the 121 proposals received three dealt with studying the cosmological background radiation though these proposals lost out to the infrared astronomical satellite iras their strength made nasa further explore the idea in 1976 nasa formed a committee of members from each of 1974 s three proposal teams to put together their ideas for such a satellite a year later this committee suggested a polar orbiting satellite called cobe to be launched by either a delta 5920 8 launch vehicle or the space shuttle it would contain the following instruments 6 instruments instrument acronym description principal investigator differential microwave radiometer dmr microwave instrument that would map variations or anisotropies in the cosmic microwave background cmb radiation george f smoot iii diffuse infrared background experiment dirbe multiwavelength infrared detector used to map dust emission michael g hauser far infrared absolute spectrophotometer firas spectrophotometer used to measure the spectrum of the cmb john c mather launch of the cobe spacecraft on 18 november 1989 nasa accepted the proposal provided that the costs be kept under us 30 million excluding launcher and data analysis due to cost overruns in the explorer program due to iras work on constructing the satellite at goddard space flight center gsfc did not begin until 1981 to save costs the infrared detectors and liquid helium dewar on cobe would be similar to those used on the infrared astronomical satellite iras cobe was originally planned to be launched on a space shuttle mission sts 82 b in 1988 from vandenberg air force base but the challenger explosion delayed this plan when the shuttles were grounded nasa prevented cobe s engineers from going to other space companies to launch cobe and eventually a redesigned cobe was placed into sun synchronous orbit on 18 november 1989 aboard a delta launch vehicle on 23 april 1992 cobe scientists announced at the aps april meeting in washington d c the finding of the primordial seeds cmbe anisotropy in data from the dmr instrument until then the other instruments were unable to see the template 7 the following day the new york times ran the story on the front page explaining the finding as the first evidence revealing how an initially smooth cosmos evolved into today s panorama of stars galaxies and gigantic clusters of galaxies 8 the nobel prize in physics for 2006 was jointly awarded to john c mather nasa goddard space flight center and george f smoot iii university of california berkeley for their discovery of the blackbody form and anisotropy of the cosmic microwave background radiation 4 spacecraft edit part of a series on physical cosmology big bang universe age of the universe chronology of the universe early universe inflation baryogenesis nucleosynthesis backgrounds gravitational wave gwb microwave cmb neutrino cnb expansion and future hubble s law redshift expansion of the universe flrw metric friedmann equations lambda cdm model future of an expanding universe ultimate fate of the universe components and structure components dark energy dark matter photons baryons structure shape of the universe galaxy filament galaxy formation large quasar group large scale structure reionization structure formation experiments black hole initiative bhi boomerang cosmic background explorer cobe dark energy survey planck space observatory sloan digital sky survey sdss 2df galaxy redshift survey 2df wilkinson microwave anisotropy probe wmap scientists aaronson alfvén alpher copernicus de sitter dicke ehlers einstein ellis friedmann galileo gamow guth hawking hubble huygens kepler lemaître mather newton penrose penzias rubin schmidt smoot suntzeff sunyaev tolman wilson zeldovich list of cosmologists subject history discovery of cosmic microwave background radiation history of the big bang theory timeline of cosmological theories category astronomy portal v t e diagram of cobe spacecraft cobe was an explorer class satellite with technology borrowed heavily from iras but with some unique characteristics the need to control and measure all the sources of systematic errors required a rigorous and integrated design cobe would have to operate for a minimum of 6 months and constrain the amount of radio interference from the ground cobe and other satellites as well as radiative interference from the earth sun and moon 9 the instruments required temperature stability and to maintain gain and a high level of cleanliness to reduce entry of stray light and thermal emission from particulates the need to control systematic error in the measurement of the cmb anisotropy and measuring the zodiacal cloud at different elongation angles for subsequent modeling required that the satellite rotate at a 0 8 rpm spin rate 9 the spin axis is also tilted back from the orbital velocity vector as a precaution against possible deposits of residual atmospheric gas on the optics as well as against the infrared glow that would result from fast neutral particles hitting its surfaces at extremely high speed in order to meet the twin demands of slow rotation and three axis attitude control a sophisticated pair of yaw angular momentum wheels were employed with their axis oriented along the spin axis 9 these wheels were used to carry an angular momentum opposite that of the entire spacecraft in order to create a zero net angular momentum system the orbit would prove to be determined based on the specifics of the spacecraft s mission the overriding considerations were the need for full sky coverage the need to eliminate stray radiation from the instruments and the need to maintain thermal stability of the dewar and the instruments 9 a circular sun synchronous orbit satisfied all these requirements a 900 km 560 mi altitude orbit with a 99 inclination was chosen as it fit within the capabilities of either a space shuttle with an auxiliary propulsion on cobe or a delta launch vehicle this altitude was a good compromise between earth s radiation and the charged particles in earth s radiation belts at higher altitudes an ascending node at 18 00 was chosen to allow cobe to follow the boundary between sunlight and darkness on earth throughout the year the orbit combined with the spin axis made it possible to keep the earth and the sun continually below the plane of the shield allowing a full sky scan every six months the last two important parts pertaining to the cobe mission were the dewar and sun earth shield the dewar was a 650 l 140 imp gal 170 us gal superfluid helium cryostat designed to keep the firas and dirbe instruments cooled during the duration of the mission it was based on the same design as one used on iras and was able to vent helium along the spin axis near the communication arrays the conical sun earth shield protected the instruments from direct solar and earth based radiation as well as radio interference from earth and the cobe s transmitting antenna its multilayer insulating blankets provided thermal isolation for the dewar 9 in january 1994 engineering operations concluded and the operation of the spacecraft was transferred to wallops flight facility wff for use as a test satellite 5 instruments edit differential microwave radiometers dmr edit the differential microwave radiometer dmr investigation uses three differential radiometers to map the sky at 31 4 53 and 90 ghz the radiometers are distributed around the outer surface of the cryostat each radiometer employs a pair of horn antennas viewing at 30 from the spin axis of the spacecraft measuring the differential temperature between points in the sky separated by 60 at each frequency there are two channels for dual polarization measurements for improved sensitivity and for reliability each radiometer is a microwave receiver whose input is switched rapidly between the two horn antennas obtaining the difference in brightness of two fields of view 7 in diameter located 60 apart and 30 from the axis of the spacecraft high sensitivity is achieved by temperature stabilization at 300 k for 31 4 ghz and at 140 k for 53 and 90 ghz by spacecraft spin and by the ability to integrate over the entire year sensitivity to large scale anisotropies is about 3e 5 k the instrument weighs 120 kg 260 lb uses 114 watts and has a data rate of 500 bit s 10 diffuse infrared background experiment dirbe edit the diffuse infrared background experiment dirbe consists of a cryogenically cooled to 2 k multiband radiometer used to investigate diffuse infrared radiation from 1 to 300 micrometres the instrument measures the absolute flux in 10 wavelength bands with a 1 field of view pointed 30 off the spin axis detectors photoconductors and filters for the 8 to 100 micrometre channels are the same as for the iras mission bolometers are used for the longest wavelength channel 120 to 300 micrometres the telescope is a well baffled off axis gregorian flux collector with re imaging the instrument weighs approximately 34 kg 75 lb uses 100 w and has a data rate of 1700 bit s 11 far infrared absolute spectrophotometer firas edit the far infrared absolute spectrophotometer firas is a cryogenically cooled polarizing michelson interferometer used as a fourier transform spectrometer the instrument points along the spin axis and has a 7 field of view this device measures the spectrum to a precision of 1 1000 of the peak flux at 1 7 mm 0 067 in for each 7 field of view on the sky over the range 0 1 to 10 mm 0 39 in the firas uses a special flared trumpet horn flux collector having very low sidelobe levels and an external calibrator covering the entire beam precise temperature regulation and calibration are required the instrument has a differential input to compare the sky with an internal reference at 3 k this feature provides immunity from systematic errors in the spectrometer and contributes significantly to the ability to detect small deviations from a blackbody spectrum the instrument weighs 60 kg 130 lb uses 84 watts and has a data rate of 1200 bit s 12 scientific findings edit the map of the cmb anisotropy formed from data taken by the cobe spacecraft the science mission was conducted by the three instruments detailed previously dirbe firas and dmr the instruments overlapped in wavelength coverage providing consistency check on measurements in the regions of spectral overlap and assistance in discriminating signals from our galaxy solar system and cmb 9 cobe s instruments would fulfill each of their objectives as well as making observations that would have implications outside cobe s initial scope black body curve of cmb edit data from cobe showed a perfect fit between the black body curve predicted by big bang theory and that observed in the microwave background the error bars are smaller than the width of the blue curve the red crosses merely locate the data points comparison of cmb results from cobe wmap and planck 21 march 2013 during the 15 year long period between the proposal and launch of cobe there were two significant astronomical developments first in 1981 two teams of astronomers one led by david wilkinson of princeton university and the other by francesco melchiorri of the university of florence simultaneously announced that they detected a quadrupole distribution of cmb using balloon borne instruments this finding would have been the detection of the black body distribution of cmb that firas on cobe was to measure in particular the florence group claimed a detection of intermediate angular scale anisotropies at the level 100 microkelvins 13 in agreement with later measurements made by the boomerang experiment however a number of other experiments attempted to duplicate their results and were unable to do so 6 second in 1987 a japanese american team led by andrew e lange and paul richards of university of california berkeley and toshio matsumoto of nagoya university made an announcement that cmb was not that of a true black body 14 in a sounding rocket experiment they detected an excess brightness at 0 5 and 0 7 mm 0 028 in wavelengths with these developments serving as a backdrop to cobe s mission scientists eagerly awaited results from firas the results of firas were startling in that they showed a perfect fit of the cmb and the theoretical curve for a black body at a temperature of 2 7 k in contrast to the berkeley nagoya results firas measurements were made by measuring the spectral difference between a 7 patch of the sky against an internal black body the interferometer in firas covered between 2 and 95 cm 1 in two bands separated at 20 cm 1 there are two scan lengths short and long and two scan speeds fast and slow for a total of four different scan modes the data were collected over a ten month period 15 intrinsic anisotropy of cmb edit data obtained at each of t...