Friday, November 29, 2013

Goodbye Comet ISON

Comet ISON appears to have broken up and evaporated as it approached the Sun, so we won't be seeing a spectacular show in our December skies as hoped. It seems unlikely that any remnants that do make it back out towards Earth's orbit will be much to look at.

The embedded YouTUBE video of pretty low quality, but NASA's website has high quality video versions of Comet ISON fizzling available for viewing and downloading here.

Thursday, November 28, 2013


I'm hoping that Comet ISON makes for a naked-eye spectacular in December so that the boys get to see a great comet. I still remember seeing Halley when I was a kid.

In the mean time the NASA Comet ISON Observing Campaign is the page I'm keeping an eye on. With ISON so close to the Sun it's up to serious instrumentation to keep an eye on it (don't try it yourself). Two in particular are the ones to watch:

[SOHO LASCO image of the sun on November 27th, 2013, showing Comet ISON on the bottom right. Note that the Sun itself is blocked in this image so as to reveal faint coronal material, in this case a Coronal Mass Ejection towards the bottom of the image.]

Friday, April 19, 2013

Exoplanet info-graphic from the NYT

I've been busy, but as I have a free moment I thought I should link to this info-graphic created by the NYT showing all the exoplanet systems discovered user Kepler so far.

When sorted by size our Solar System (just the inner three planets) is at the bottom of the page, which goes to show you how strongly weighted Kepler's method is toward detecting exoplanets with small orbital radii.

This bias toward smaller orbital radii true of the majority of current exoplanet discovery methods, but not to the same degree. has a nice interactive plotting tool, which I used to plot all discovered exoplanets (not just Kepler) as a function of orbital radius (x-axis),  planet mass with respect to Jupiter (the Earth is 0.00315 times the mass of Jupiter) and host star mass (the size of the symbol).

Exoplanet mass versus oribital radius
Exoplanet mass versus orbital radius