Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Outer space mission LISA Pathfinder: Fraunhofer IZFP puts two gold/platinum cubes to the acid test

02.03.2016

Until a few days ago – when the long-awaited epochal breakthrough of direct proof of gravitational waves was proclaimed at a press conference – in spite of intensive research scientists and researchers failed to verify the existence of gravitational waves as predicted by Albert Einstein's theory of general relativity.

Just on this account, the European Space Agency has sent a satellite into space which is to perform the preparatory work for the direct detection of gravitational waves predicted by Einstein. The central experiment of the mission involves two virtually identical high-precision cubes made of a gold-platinum alloy. These cubes were tested by engineers at Fraunhofer IZFP for their suitability and accuracy, both prerequisites for their smooth operation in space.


LISA Pathfinder in outer space

ESA–C. Carreau

LISA Pathfinder is a pre-project of a possible LISA-like mission, which is to track down both, gravitational waves and, in particular, their sources in deep space: Since December 2015, the LISA Pathfinder satellite (Laser Interferometer Space Antenna) was traveling in the outer space to its final orbit. Mid-February, approximately one and a half million kilometers from Earth, LISA Pathfinder carried out the last function tests of the scientific payload.

In early March, the actual, six-month mission is to begin. LISA Pathfinder has been approved by the "Science Programme Committee" of the ESA in November 2000 and launched on December 3, 2015.

Amongst others, two gold-platinum cubes serving as test masses are on board, each being held in a separate vacuum vessel. After reaching the final position in space they are released and then, positioned in zero gravity, floating freely.

Their respective positions – the cubes float in 38 cm distance from each other – have to be stable with considerable precision and must be monitored accordingly. The measurement of the relative accuracy of the positioning in the picometer range is crucial for the success of future gravitational wave experiments.

Another serious criterion for measuring the gravitational waves is given by the shape accuracy of the cubes’ surface structure: Both cubes must have one extremely precisely shaped surface whose deviation from the ideal shape is subject to extremely narrow limits. Only within these limits the provided measures can succeed.

With regard to the fulfillment of these extreme requirements both two kilogram cubes were put to the acid test by Fraunhofer IZFP’s engineers and scientists: In the test laboratories of this Saarland Institute high-frequency ultrasound examinations of the gold cubes’ near-surface regions were carried out, which are able to detect hidden cavities and inclusions down to a scale of 50 micrometers.

These investigations resulted in insights concerning the question of whether the cubes’ gravitational homogeneity is sufficient. Likewise, they substantially affected the decision of which side of each cube is to be processed further to "specular surfaces".

Background information concerning LISA Pathfinder and gravitational waves:
Beside ESA research institutes and industrial enterprises from Italy, Germany, UK, Spain, Switzerland, France and Netherlands participate in LISA Pathfinder (information by Deutsches Raumfahrtzentrum DLR).
As a space systems company Airbus Defence and Space GmbH (Friedrichshafen) is responsible for system integration and verification of the “LISA Technology Package” (LTP) instrument. The subsystems and modules of LTP are provided via the national space agencies and the European Space Agency by a consortium of European companies and research institutes such as the Max Planck Institute for Gravitational Physics or the Albert Einstein Institute in Hannover (AEI).

Weitere Informationen:

http://www.izfp.fraunhofer.de/en.html

Sabine Poitevin-Burbes | Fraunhofer-Institut für Zerstörungsfreie Prüfverfahren IZFP

More articles from Earth Sciences:

nachricht Predicting unpredictability: Information theory offers new way to read ice cores
07.12.2016 | Santa Fe Institute

nachricht Sea ice hit record lows in November
07.12.2016 | University of Colorado at Boulder

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>