Now, there is a big number. Care to guess what it represents? Time’s up. This would be “The WISE Source Catalog,” which “contains the attributes for 563,921,584 point-like and resolved objects detected on the Atlas Intensity images. Catalog sources are required to have a measured SNR>5 in at least one band, and to meet other criteria to ensure a high degree of reliability.” There were 284,000,000 other objects that were identified but failed to meet the above criterion. So, now you know what you can do to keep your mind active in retirement. Pick one, or 100, or 100,000 of these and try to help the astronomers figure out what it all means. This is one of many sky surveys, currently a focus of astronomy missions.
This one, WISE, stands for Wide-field Infrared Survey Explorer. “WISE imaged the entire sky with multiple, independent exposures during its full cryogenic survey. All four bands were imaged simultaneously during each exposure, and the exposure times were 7.7 sec in W1 and W2 and 8.8 sec in W3 and W4. As illustrated in Figure 1, the survey scanning strategy resulted in 12 to 13 exposures of each point on the ecliptic plane. Coverage increases to over 3000 exposures at the ecliptic poles. WISE completed its first complete sky coverage on 17 July 2010 and surveyed approximately 20% of the sky a second time before the end of the full cryogenic mission phase.”
ORA’s (now Synopsys’) own Mark Kahan was a significant contributor to the review panel that monitored the design through deployment of the WISE system. I’ll keep this short so you push the button. DO GO to the link and check it out a bit. Although there are more survey telescopes to come, including the ground-based Large Synoptic Survey Telescope (LSST), which will be described in an upcoming blog, one could argue that the astronomical analysts have enough on their collective plate for awhile.
Below is my favorite from a short visit to the site (click on past images at the bottom of the page; this one is from July 8, 2009). This is a collection of the 258 nearest galaxies. Why 258, you ask? This is the number of galaxies included in the so-called Local Volume Legacy Survey, built from GALEX and Spitzer Images, and intended to include all galaxies within 3.5 Mpc and a complete sample within 11 Mpc (see https://iopscience.iop.org/0004-637X/703/1/517/pdf/0004-637X_703_1_517.pdf). WISE's data will likely undergo similar processing in the future.
Galaxies in the Local Volume Legacy survey (LVL), a study of 258 of the nearest galaxies. In these three-color images, 3.6 um emission is blue, 8 um emission is green, and 24 um emission is red. Credit: Shawn Staudaher (U. Wyoming) and the LVL team.