No Mistaking Astronomical Objects

On Starts With a Bang, Ethan Siegel makes headway on his tour of “110 spectacular deep-sky objects” first cataloged by Charles Messier in 1758.  Before powerful telescopes were developed, the heavens consisted of the sun, moon, stars, a few bright planets, and the rare passing comet.  Comets were actively sought by men like Messier, who one night saw a bright smudge—too ill-defined to be a star—that “neither brightened nor changed position nor altered in appearance over the subsequent nights.”  He had spotted the beautiful Crab Nebula, an expanding lacework of stardust blown out by a supernova within our own galaxy.  Unknown to Messier, some of his nebulae were entirely different galaxies, millions of light years distant, a structure scarcely conceived of in the 18th century (and not proven, on the basis of redshift, until 1912).  Other Messier objects turn out to be spectacular star clusters, such as M13, which contains about 300,000 stars “from Sun-like ones down to red dwarfs and white dwarfs, a few blue stragglers (common to globulars), and a few red giant stars” within a diameter of 145 light years.  But all these wonders of the universe looked about the same to Messier: things not to confuse with comets, ice orbiting the sun.

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Too Much; Not Enough

On Starts With a Bang, Ethan Siegel investigates the hamstringing of the James Webb Space Telescope. Originally scheduled to launch in 2013 at a cost of $5.1 billion, the JWST was pushed to 2015 and $6.5 billion by a government review panel that faulted NASA mismanagement. But the revised numbers counted on timely infusions of cash, and because “a miserly US Congress” withheld them, the cost of the project ballooned to $8.7 billion, with a new launch date of 2018. Although its unprecedented mirrors are nearly finished—along with its electrical instruments and their housing—the JWST still waits on its massive sunshield, which means the project will stay grounded even as its price tag gets more astronomical. [UPDATE: funding for the JWST has been restored!] Meanwhile, on Uncertain Principles, Chad Orzel imagines an ark defined by qubits instead of cubits. God decrees, “thou shalt take into thine ark all of the numbers,” to which Noah astutely replies, “if the ark is to be 300 by 50 by 30 qubits, then the maximum number to be stored within it must be no greater than 2450000.” The supreme being asks if this is not close enough to infinity—and threatens to start smiting things when Noah suggests including more than just positive integers.