Scanning pattern in Planck's maps

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In summary, the Planck picture shows a scanning pattern in the sky that is not caused by contamination, and it is intended to eliminate foreground contamination. This scanning pattern is bad news for the Big Bang theory as it suggests that CMB fluctuations diminish as you average over scans.
  • #1
zonde
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There is a year old Planck picture:
The sky seen through Planck's nine frequency channels
There is no other data just this picture. But it is very intriguing just the same.

In 70GHz 100GHz frequency maps there is clear scanning pattern visible. And 143GHz frequency map shows stripes that are related to scanning pattern.

So it looks like CMB fluctuations diminish as you average over scans that are taken at different positions of satellite.

If that indeed is so it would be very bad news for Big Bang as source of CMB fluctuations (or CMB itself) would seem to be something related to this observation:
http://www.physorg.com/news/2011-06-big-edge-solar.html

I am wondering if that is the reason why there is nothing on that topic. Because if you intend to say something against mainstream viewpoint you want to be really sure about your data. So you will double check and triple check everything.
 
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  • #2
This map is intended to eliminate foreground contamination due the milky way. I don't see the correlation.
 
  • #3
zonde said:
There is a year old Planck picture:
The sky seen through Planck's nine frequency channels
There is no other data just this picture. But it is very intriguing just the same.

In 70GHz 100GHz frequency maps there is clear scanning pattern visible. And 143GHz frequency map shows stripes that are related to scanning pattern.

So it looks like CMB fluctuations diminish as you average over scans that are taken at different positions of satellite.

If that indeed is so it would be very bad news for Big Bang as source of CMB fluctuations (or CMB itself) would seem to be something related to this observation:
http://www.physorg.com/news/2011-06-big-edge-solar.html

I am wondering if that is the reason why there is nothing on that topic. Because if you intend to say something against mainstream viewpoint you want to be really sure about your data. So you will double check and triple check everything.
Actually, most of the visual effect there is not due to any contamination of the data (except possibly at 143GHz and 217GHz), but rather due to the fact that different parts of the sky have been covered a different number of times. At any rate, there has been a lot of work since then in cleaning up those maps, and there remains quite a lot of work left to go. We also have more than two full years of data now, so the coverage is much better.

The current plan is to do the first CMB data release in a little less than a year, and so the work over this next year is going to be geared towards making sure all of our data products are in as solid a shape as possible.
 
  • #4
zonde said:
So it looks like CMB fluctuations diminish as you average over scans that are taken at different positions of satellite.
...

Those pictures say nothing at all about the CMB. It says clearly that they are images of the FOREGROUND with all the CMB data subtracted out.

So those maps that you link to, they show precisely what would NOT be included in the CMB sky maps that Planck makes.

If you want to say anything you should probably get the actual CMB maps from Planck. Or from the preceding mission WMAP, if you cannot get ones from Planck.
 
  • #5
Ah, stupid me not noticing word "foreground".
Thanks, Marcus!
 

1. What is a scanning pattern in Planck's maps?

A scanning pattern in Planck's maps refers to the way in which the Planck spacecraft scans the sky to create its maps of the cosmic microwave background radiation. The spacecraft follows a specific pattern of rotations and movements to ensure that all areas of the sky are observed evenly.

2. Why is the scanning pattern important in Planck's maps?

The scanning pattern is important because it allows for a more accurate and complete map of the cosmic microwave background radiation. By scanning the sky in a specific pattern, Planck is able to reduce any potential biases and ensure that all areas are observed with equal sensitivity.

3. How does the scanning pattern affect the resolution of Planck's maps?

The scanning pattern does not directly affect the resolution of Planck's maps. However, by covering the entire sky multiple times, the spacecraft is able to create maps with a higher resolution and sensitivity, as any potential errors or noise can be reduced through averaging.

4. Can the scanning pattern be changed or adjusted by scientists?

No, the scanning pattern is pre-programmed into the Planck spacecraft and cannot be changed or adjusted by scientists on Earth. However, the spacecraft is able to make small corrections in its movements to ensure accurate observations.

5. How long does it take for Planck to complete one scanning pattern?

The scanning pattern for Planck takes approximately six months to complete, as the spacecraft rotates and scans the entire sky multiple times. However, the spacecraft continues to collect data and make observations during this time, so the final maps are a combination of all the data collected over the six-month period.

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