Jump to content

Astronomy Stuff


Recommended Posts

18 hours ago, Bobbie Bobster said:

Some negative comment around this in the industry. If FH goes bang close to historic pad 39A it could severely compromise the schedule for testing crewed Dragon flights to ISS. The car stunt wouldn't look that good then.

They almost certainly expect it to blow up (and by christ yessir, it's going to be an almighty explosion!). They will of course try their hardest to make it work, but as they've demonstrated with their numerous failures before getting it right with the drone barge landings, they're not afraid of failing, and well, blowing itself to smithereens demonstrates that they're they are breaking new ground

Link to comment
Share on other sites

  • 1 month later...
11 hours ago, manxy said:

And moving on down the list of information which may or may not prove enlightening

Does the moon reflect the sun or not? 

Manxy, I don't think the flat earth thread is a good vehicle for you to post your random queries about science which have absolutely nothing to do with the sociological issue that many thousands of people are so ignorant of evidence and so poor at collecting and understanding it that they think the earth is flat.

You question is basically astronomical, so I'll answer it here in the forum's astronomy thread.

Moonlight is a big problem for astronomers.  They like dark skies where the light they collect arrives directly from the stars etc they are observing.  Astronomers usually take a spectrum of the light they are observing - basically splitting the light up via a prism into a rainbow and measuring how bright it is through the different colours (frequency).

Moonlight messes this up as it scatters in the atmosphere by bouncing off the atoms and hence rather than collecting a pristine spectrum of a star many light years away (or whatever) they get one contaminated by moonlight.

So what do they do?

They collect a moonlight spectrum and subtract this from their results - ie they basically point their telescope at an empty portion of sky for the same amount of time they were pointing it at the star and then take away that result from the star's spectrum.

We know quite a lot about the moon's spectrum.

Here are a couple of nice approaches: -

One which explains how a model was developed to account for moonlight scatter from different phases and positions of the moon in the sky.

and one which uses the difference in spectrum from the bright, light part of the moon compared to the dark part in the crescent moon to produce an earth glow spectrum caused by the dark side been lit up by the earth, to model how the earth would look from space.

The moon spectrum is the sun spectrum altered by the effect of reflection and scattering from the moon's surface.  That is science.

  • Thanks 1
Link to comment
Share on other sites

  • 2 weeks later...


Space X Falcon Heavy has been on launch pad 39A at Kennedy Space Centre for several days, and is reported to have been fuelled up for a full engine test, possibly today.  Still no published launch date for the demo flight.

Edited by guzzi
Link to comment
Share on other sites

  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Create New...