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ASTR1001 Zog: The Third Data Release. Smoot and Hawkins. These reseaarchers built a satellite to measure the microwave background radiation. Using ground-based microwave telescopes, it was quickly established that a microwave background does indeed exist.
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Smoot and Hawkins • These reseaarchers built a satellite to measure the microwave background radiation. • Using ground-based microwave telescopes, it was quickly established that a microwave background does indeed exist. • Their Cosmic Background Explorer satellite was launched to measure this background precisely. • The microwave background was rapidly discovered to vary in brightness across the sky. It is about 10% brighter in the direction of both blue spots than it is at Declination zero.
Here is an all-sky map of the microwave background. Declination zero is along the middle. Declination +90 is at the top and -90 is at the bottom. The intensity at declination +90 or -90 is 10% greater than that at Declination 0.
When this simple correlation with declination is removed from the data, some residual lumps are seen. These residual brightness patterns have an amplitude of about 0.001% (ie. the brightest bits are 0.001% brighter than the faintest bits). • Remarkably, the pattern of bright and dark regions looking towards Declination +90 and -90 are the same! The same structures are seen! • The structures do not seem to correlate with fuzzballs or the milkstains. 0 RA 0 RA 90 RA 90 RA +90 Dec: North -90 Dec: South
Fidelis and Semper • This group requested BST spectra of the objects found in the Bubble Deep Field, in particular the blue galaxy-like objects, the small red objects, and the objects that look like fuzzy balls. • The time allocation committee rejected this proposal: given that it took 120 orbits to even get an image of these things, obtaining spectra would require about 10,000 orbits - four years of exclusive BST time. The committee were not convinced that useful science would come out of this colossal investment of time. • The group did, however, persuade some collaborators with access to the Keck Telescope, Zog’s biggest ground-based telescope, to get spectra of a few of the brightest sources in the Bubble Deep Field. The small red objects were far too faint to obtain spectra, but a few ratty spectra were obtained of the brightest blue elongated things and the grey fuzzy balls.
The Bubble Deep Field: 120 orbits exposure with the Wide Field Planetary Camera 2.
The blue, elongated things had featureless, blue spectra. No emission or absorption-lines were seen, but the signal-to-noise ratio of the spectra was so poor that this wasn’t really a surprise (these are very difficult things to get spectra of). Relative Flux 300nm 700nm Observed Wavelength (nm)
The faint fuzzy things had rather different spectra, though still pretty ratty. Here is a typical one. Relative Flux 600 900 300 Observed Wavelength (nm)
Walrus et al. • Walrus et al are experimental physicists. Hearing all the talk about strange geometries, they requested money to build an instrument to measure p. • Two instruments were built: one to measure it in the lab, and one to measure it on much larger scales in space (by bouncing lasers between spacecraft). • The ground-based experiment reported that p had its normal, expected value with a precision of 15 decimal places. • The space-based experiment measured p on a scale of 1012m, and once again found that it has its normal expected value, to an accuracy this time of 10 decimal places.
Gabriel, Nunn and Weekes (ANU) • Gabriel et al. requested an X-ray measurement of the famous radio source M12. • The observations were made, and a very strong emission was detected: 149 X-rays per second.
The European Zpace Agency (EZA) • EZA have long been concerned that not enough is known about nearby stars. The fundamental problem has always been measuring the distances to stars: unless you know the distance, everything else is very hard to determine. They recently launched the Hipparchoz satellite, designed to measure parallax with unprecedented precision to all stars within about 30 pc. • When its two year mission was completed, it took the team scientists another two years to process the vast amounts of data.
Parallax Measurements • Despite the enormous increase in precision, no parallax was measured for either blue spot. Likewise, no fuzzball showed parallax, and none of the stars in the GMS showed measurable parallax. • Over 7,000 nearby stars did, however, show parallax. Of particular interest were 4 pulsing stars with two hour periods. These stars were chosen because their spectra were very similar to the two-hour pulsing stars seen in the GMS and in other fuzzballs. • Parallaxes are measured in arcseconds (and arcsecond is 1/60 arcminutes. An arc-minute is 1/60 degrees). They represent the change in apparent position over half a Zog year (ie. The coordinates of the star change by this angle between two observations six months apart).
Radar Measurements • Radar pulses sent to Zog’s sun take 18 minutes 53.33 seconds to make the round trip to the sun and back. • The speed of light, as measured in Zoggian laboratories, is the same as it is on Earth.
