Comments for Psychogeeks

Comment on When Stars Blink Out by Chris

Chris — Sat, 17 May 2008 22:00:44 +0000

Hi Christine,

Thanks for the question. Unfortunately, probably not.

It is possible that you chanced upon an occultation (like in the article) but these are typically a single disappearance event lasting a few seconds. They’re also fairly rare events on naked-eye visible stars.

Most of the variations you see in a star’s brightness are the result of turbulence in our atmosphere. The path of light from the star to your eye is bent by the air, which as it moves, moves some of the star’s light in and out of your vision. This is the twinkling star of nursery rhyme fame, and also why astronomer’s want to put telescopes (like Hubble) above the air.

Another effect comes about when one stares directly at a point-like light light. Every so often, as your eye naturally twitches about, the star’s light will fall onto the end of your optic nerve… a blind spot in your vision. The star “disappears” but quickly reappears.

If you had seen a star that, over minutes, got massively bright (say as bright as the Moon) before fading gradually then you might have seen a supernova. That would be a truly magnificent event that should be reported to your local observatory with a location in the sky.

I hope this helps,
Chris W

Comment on When Stars Blink Out by christine

christine — Sat, 17 May 2008 04:18:04 +0000

hi just a question last night me and a friend were looking at a star and it was dimming to nothing and then would reappear it was doing this erratically more then once is it a dying star? it may be still in the sky tonight we didn’t see it fall i wish i could give more information on which star my friend said it may be the morning star because it was brighter and lower then the others

Comment on Computational Astrophysics (HET617) by John Ferreirinho

John Ferreirinho — Fri, 04 Apr 2008 03:00:50 +0000

Very interesting, thanks. I’m still having trouble visualzing what’s going in those horsehoe orbits, but I expect looking at some detailed animations would clarify this.

Comment on Science Projects in a Small World by Cheeky

Cheeky — Thu, 20 Sep 2007 01:42:30 +0000

Makes ya wanna sing…”It’s a small world after all….”

Sorry, couldn’t help myself

Comment on Fountains on Io by Chris W

Chris W — Mon, 18 Jun 2007 22:06:45 +0000

I know it was certainly a surprise to the folks running the Voyager probes back in 1979. Nobody expected a body as small as Io to be volcanically active, and it took some time to come up with a plausible explanation. Even more surprising was the discovery of geyser-like eruptions of nitrogen gas and dust on Neptune’s moon Triton. Still trying to get to grips with that one.

Comment on Fountains on Io by Wes

Wes — Mon, 18 Jun 2007 12:59:24 +0000

These are quite spectacular images. Although you’ve already discussed it, who would have thought that this activity would be going on in those far reaches of our system?

Comment on When Stars Blink Out by Eris Puts On Weight

Eris Puts On Weight — Sat, 16 Jun 2007 07:33:44 +0000

[...] body and some assumptions. Later Hubble Space Telescope observations of Eris as it occulted a star (More on occultations) allowed the size estimate to be refined to 2400±100 km [3]… very similar to Pluto. [...]

Comment on Volcanic Plumes on Io by Fountains on Io

Fountains on Io — Mon, 11 Jun 2007 02:00:11 +0000

[...] few weeks ago I wrote about my reasons for choosing an image of the volcanic plumes on Io as one of my banner images. The NASA New Horizons mission to Pluto and the Kuiper belt has captured [...]

Comment on In Saturn’s Shadow by Wes

Wes — Fri, 01 Jun 2007 15:04:09 +0000

Wasn’t it Zaphod Beeblebrox in the Total Perspective Vortex who saw himself as the centre of his own Universe? It is things like this which make me feel that we are a mere blip in the cosmos. Thanks for sharing!

Comment on Tee Shirt Astronomy by Chris

Chris — Wed, 23 May 2007 01:48:14 +0000

Indeed it does bear a resemblance… inspiration perhaps?