Gaia 'billion star surveyor' lifts off

[escher]

Gaia 'billion star surveyor' lifts off

Successful liftoff.

Hope rest of her journey and mission be good as well.

To her final position
[video=youtube;9XcJ1wFRCk8]http://www.youtube.com/watch?v=9XcJ1wFRCk8#t[/video]

 

[escher]

And what she will be doing there

[video=youtube;BnFyzZGWuYs]http://www.youtube.com/watch?v=BnFyzZGWuYs[/video]

 

[escher]

Gaia launch replay highlights

[video=youtube;xDmQvJVJg8Y]http://www.youtube.com/watch?v=xDmQvJVJg8Y[/video]

 

[escher]

[video=youtube;oGri4YNggoc]http://www.youtube.com/watch?v=oGri4YNggoc[/video]

 

[Leongsam]

I dedicate this mission to my beloved Lee Kuan Yew. Long live Mr Lee.

 

[escher]

I dedicate this mission to my beloved Lee Kuan Yew. Long live Mr Lee.

I feel so shamed. I must not be remissed in my dedication to LKY.

In turn, I dedicate below to that smear of shit on sole of shoe Lee Kuan Yew.
May he be buried below there

The only place fit for that smear of shit on sole of shoe LKY to be buried under

Bury that bastard LKY under a public toilet or in sewerage treatment plant.
Sinkies shit on him or flowing around him will purify that bastard LKY
The stink of our shit will smell a lot better than that smear of shit on sole of shoe LKY.

 

[escher]

A billion pixel camera for a billion stars.
How that billion pixel camera works.

[video=youtube;bbfb8VhH7L0]http://www.youtube.com/watch?v=bbfb8VhH7L0[/video]

 

[escher]

ESA's billion-star surveyor Gaia is now in its operational orbit around a gravitationally stable virtual point in space called 'L2', 1.5 million km from Earth.


Gaia enters its operational orbit

 

[escher]

The flight dynamics expertise behind Gaia’s critical manoeuvre
http://blogs.esa.int/gaia/2014/01/07/the-flight-dynamics-expertise-behind-gaias-critical-manoeuvre/

 

[Leongsam]

The flight dynamics expertise behind Gaia’s critical manoeuvre
http://blogs.esa.int/gaia/2014/01/07/the-flight-dynamics-expertise-behind-gaias-critical-manoeuvre/

Those who are wondering what all this about first have to get their heads around the concept of Lagrangian points. Otherwise, it is impossible to visualise how an object can orbit around nothing more than a point in space.

You can see from the gravitational contour map that L1 and L2 are very unstable points and constant intervention is needed to prevent any object at that point from falling off. L4 and L5 are a lot more stable. You can see a dynamic simulation of this at http://www.princeton.edu/~rvdb/JAVA/astro/galaxy/Galaxy.html

L4 and L5 is where you will find the earth's trojan asteroids that are orbiting outside of the earth's orbit but at the same frequency of 365.25 days.

 

[Leongsam]

Found a video which explains everything very clearly.

 

[escher]

It is said a picture is worth a thousand words

And more on the EL Two

Gaia goes to L2 – what’s an “ell-two”?

 

[escher]

Watch Gaia Go From Lab to Launch in Two Minutes

 

[escher]

With a final, modest, thruster burn yesterday afternoon, ESA’s billion-star surveyor finalised its entry into orbit around ‘L2’

 

[escher]

GAIA COMES INTO FOCUS

 

[escher]

ONE MONTH AT L2

 

[escher]

As part of the tests to try and diagnose the stray light issue noticed in the first month of instrument commissioning, the Gaia operations team is making a series of spacecraft orientation changes.

The spacecraft was first tilted from 45 to 42 degrees and then to 0 degrees, that is, facing its sunshield directly at the Sun. Then the spacecraft was returned to 45 degrees.

 

[escher]

The work done to bring online all components of the Gaia service module, which houses equipment needed for the basic control and operation of the satellite, has gone very smoothly. The chemical and micro propulsion systems function well, with the latter providing tiny (micro-Newton) thrusts to maintain Gaia’s spin rate, compensating for torques due to solar radiation pressure. The phased array antenna is operating very well, ensuring that we can maintain the high data rates that are needed to downlink all the science data. And the essential rubidium atomic clock is also working to specification.

 

[escher]

GAIA TAKES SCIENCE MEASUREMENTS
As part of the on-going commissioning tests, we are happy to be able to report on the first spectroscopy observations made by Gaia.
You will have seen the ‘first light’ images from the early phases of commissioning already, but as part of these activities we have also started taking test spectroscopic measurements of known stars.
While astrometric measurements will determine the positions and motions of stars, Gaia will use spectroscopy to measure key physical properties, such as brightness, temperature, mass, age, and chemical composition.

 

[escher]

PRELIMINARY ANALYSIS OF STRAY LIGHT IMPACT AND STRATEGIES
Update from the Gaia Project Team

A series of exhaustive tests have been conducted over the past few months to characterise some anomalies that have been revealed during the commissioning of Gaia following its successful launch in December 2013, as have been discussed in previous blog posts.

Key among these are an increased background seen in Gaia’s focal plane assembly due to stray light entering the satellite and reduced transmission of the telescope optics. In an effort to understand both problems, much of the diagnostic work has been focussed on contamination due to small amounts of water trapped in the spacecraft before launch that has been “outgassing” now that Gaia is in a vacuum.