Missing Mass

and not the Cosmic Kind

I lost my cellphone a couple of days ago and spent much angsty time tearing things apart in my office, our house, etc. trying to find it. At one point I decided that it had gone where all the missing socks go when they disappear from the dryer, or wherever it is a cat goes when you want to put him in the carrier to go to the vet. It’s a strange no space where things disappear to and may or may not return.  Also at one point, when I had despaired of ever finding my trusty phone, I decided that maybe that’s what the missing mass in the universe is — socks, cellphones, keys, term papers, unpaid traffic tickets, charge slips, etc.

Fortunately, my delusion only lasted a short time. I found the cellphone and it was NOT in some cosmic or metaphysical no-space — thankfully. So, astronomers and cosmologists will have to look elsewhere for their missing mass — Petersen’s Law of Lost Cellphones is NOT the explanation. It’s still most likely dark matter.

Planet Hunting Will Commence

First Light for Kepler

Star Cluster NGC 6791 from Kepler First Light Image
NGC 6791 -- Kepler's first-light image. (Click to embiggen.)

Kepler, the planet-hunting satellite, has sent back its first light image —  a 100-square-degree patch of sky that contains a star cluster called NGC 6791. This is only a part of Kepler’s full field of view, but even from this image, it’s clear that Kepler has pretty good eyesight.

The Kepler spacecraft is equipped with a telescope and photometer, and is out there looking for planets like Earth and will be on the  hunt for the next 3.5 years.  It is focused on 100,000 pre-selected stars — and will continuously study their light output to watch for periods when these stars look a bit dimmer.  Such dips in brightness will be a very good indication that planets are crossing in front of the star, blocking out some of the light from their parent stars.

Kepler needs a very precise view to do this — and to be able to spot planets as small as Earth, the images are intentionally blurred slightly. This minimizes the number of saturated stars. Saturation, or “blooming,” occurs when the brightest stars overload individual pixels, causing the signal to spill out into nearby pixels.

The mission scientists and technicians for Kepler are now in a period of calibration and engineering testing, which will help astronomers tweak the focus and adjust its onboard instruments.  When that work is done, the serious work of planet-hunting will get started. It’s going to be a very exciting time for planet-hunters, who are already jazzed by the numbers of planets already found. But, Kepler gives them the chance to seek out Earth-type worlds — and who knows what they’ll find.  Stay tuned!