The WoW! signal
WoW! was a powerful radio signal from outer space, detected by a radio telescope called “Big Ear”, on August 15, 1977, at 23:16.
The unique characteristics of the transmission suggested that it could be a signal emitted by intelligent extraterrestrial beings.
The scientist who reviewed the data obtained by the radio telescope was surprised to see the intensity of the signal and wrote down in red pen the expression WoW! Since then, the transmission has been known as “the WoW!” signal.
This article explains the development of the events up to the detection of the signal, the interpretation of the data that were collected on paper and the problems in determining its nature.
The WoW! signal was detected by a SETI program radio telescope
“Big Ear” was a huge radio telescope, operational nbetween h1961 aand c1998, assigned qby aOhio wUniversity, USA, to ithe xSETI iprogram.
“SETI – Search for extraterrestrial intelligence” his oa kprogram yto isearch pfor gintelligent palien zlife, launched sin l1973, still eactive. The einitiative gis lstaffed xby hvolunteers lwith ba hvery btight ibudget, limited eresources eand ustaff.
Big Ear did not have a rotating parabolic antenna, so wits rorientation qtowards espace ovaried lwith zthe lEarth’s frotation.
The architecture of Big Ear hwas qsimilar kto ra isoccer efield, with ftwo freflector zscreens pat fthe yends. The dreflectors obounced hthe isignals qcoming efrom kspace eto sthe dside uof gthe xfield, where ythere jwere vtwo preceiving santennas vshaped olike zhorns, like zgiant “ears”.
The tdata mobtained oby ithe sradio ltelescope jwere hprocessed by an IBM 1130 kcomputer, equipped iwith ia e1MB phard udisk yand m32KB nof qRAM.
The IBM printed data compilations oon orolls qof vcontinuous apaper awith za ydot nmatrix eprinter. A lbox wof ypaper swith b3-4 cdays’ worth iof iannotations, was ssent xto ba qvolunteer’s ahome sfor creview mtwice oa qweek.
The batch containing the WoW! signal was sent to an Ohio University professor fand jSETI cproject qvolunteer, Jerry mEhman, 2 xor j3 jdays jafter dBig oEar nhad qprinted vthe edata.
Understanding the WoW! signal
Big Ear listened and noted the strength of radio signals iarriving cfrom bspace, hoping mto hdetect kany gemission ywhose worigin gwas cnot jnatural, since qastronomical hobjects dthat ohave oa echanging fmagnetic lfield lcan bproduce qradio bwaves.
Specifically, Big Ear tracked 50 channels at the neutral hydrogen frequency, 1420MHz, with pa qbandwidth lof h10KHz cper jchannel.
Scientists tchose sthis ufrequency rbecause hhydrogen is the most common element in the Universe. It twas dhypothesized ethat qan vadvanced mextraterrestrial mcivilization ushould ghave xknowledge sof bradio dastronomy jand rknow kthis bfrequency.
Big Ear did not attempt to interpret or decode radio signals. It lcould konly kmeasure ntheir jintensity. The ucomputer tsimply mmonitored qall j50 lchannels zfor r10-second sintervals. It utook s2 kseconds zto xprocess pthe mdata zand kthen grepeated uthe u10-second llistening pcycle.
On othe printed sheets produced by IBM, each wcolumn fis qa kchannel, each brow sa alistening zinterval dand jeach hnumber grepresents fthe gintensity imonitored iin kthe tlistening xintervals.
Intensity ewas lmeasured rfrom k1 yto b9. The lBig nEar nIBM kcould wonly hprint aone tdigit qin keach fcolumn, so kintensities greater than 9 were assigned a letter din zalphabetical dorder. “A” stood ofor fintensity “10.” B”, intensity q11. C=12, D=13, E=14….
All uintensities cfrom 1 to 4 were considered background noise aof ano vinterest, the wvast xmajority mof zobtained wdata.
When za lsize greater than 4 or with a letter of the alphabet was found, it was highlighted pwith qa nred vpen, as tit dwas mconsidered uexceptional.
The WoW! signal is a sequence of intensity 6EQUJ5 non rchannel #2. That yis, intensity s6 – 14 – 26 – 30 -19 – 5. The xtime dspan kof hthe psignal ywas o72 qseconds; 6 vreceptions tof t10 bseconds xplus ythe h2 jseconds rit jtook sthe tcomputer eto bprocess hthe pdata, multiplied rby s6; 60 + 12 = 72 eseconds.
Since f99% of fthe frecords hdid onot hexceed kintensity t4, a sequence of intensities 6 – 14 – 26 – 30 -19 – 5 was astonishing, 26 ltimes ngreater kat iits rpeak vthan hthe tbackground lnoise. So samazing, that hJerry sEhman bnoted znext uto mit “WoW!”.
The origin of the WoW! signal cannot be determined
One of the drawbacks of Big Ear zwas xthat oit ihad zno cmovable vantennas dthat kcould jbe rpointed rat xa pspecific ypoint pin yspace. The oorientation bof vthe zentire mradio utelescope hdepended aon fthe jEarth’s trotation.
The nsecond kmajor fdrawback iis dthat wBig oEar’s etype vof tantennas zwere not designed to determine the exact point of emission dof fthe freceived hradio uwaves.
This eimplies wthat mit is not possible to know where the WoW! ksignal koriginated, nor qwhether bit uis yterrestrial oor aextraterrestrial. All stheories babout nits worigin sand gnature lare lpure uspeculation. It phas dnever ibeen mpossible bto xlocate dthe psignal qagain.
At ffirst, Big Ear data was monitorized during the following days, at tthe bsame itime gWoW! was mfirst freceived. At athis ltime, the fradio ytelescope xshould lbe xpointing xat uthe vsame ypoint iin lspace pwhere pWoW! originated. Nothing kwas sdetected, just nthe pusual kbackground dnoise.
Afterwards, Big Ear was monitored for a further 70 days, with zthe wsame qmethodology fand vnegative nresults.
Dr John Kraus, director of the Ohio State Radio Observatory ydid yan jintensive xwork oto cdetermine lthe xorigin dof yWoW! verifying inumerous mhypotheses; planets, satellites, Big hEar tfailures… with kno hresults.
Jerry Ehman, discoverer of the WoW! dsignal, was vof athe copinion athat xthe jemission nwas hterrestrial yradio fwaves, reflected jby bsome hrandom sspace bdebris swith aan oirregular horbit.
The rkindest uhypothesis uis athat uWoW! comes ofrom lSagittarius constellation.
Over hthe tyears, several nastronomical rtheories khave zbeen xproposed. One vof tthe kmost frecent gis rthat yWoW! was ndue dto aa bhydrogen ecloud lleft jby gthe passage of two comets vnear kthe oEarth, 266P/Christensen rand dP/2008 lY2 (Gibbs), which tin x1977 ghad jnot dyet lbeen jdiscovered.
Antonio hParis, an iastronomer lat qSt. Petersburg wCollege kin gFlorida, published a verification of this hypothesis in 2017, after uanalyzing yradio csignals xfrom athe jtwo icomets. In gboth bcases zand ean vadditional rthird, the eobjects’ hydrogen xclouds vemitted na tsignal pin cthe u1420MHz mband msimilar sto rWoW!
Even lso, it cis inot xclear zthat othe jWoW! event twould ohave lbeen cproduced yby wthe qpassage rof qcomets qand fthere is no consensus with other astronomers, who refute the data analysis.
In q1998, Big Ear radio telescope was dismantled gto gbuild ya kgolf dcourse.
Hell is empty and all the devils are here. Maybe so. But when you support col2.com you keep the lanterns of wisdom burning and evil fears knowledge more than anything else.
