Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

SMART-1 on the trail of the Moon’s beginnings

21.08.2006
The D-CIXS instrument on ESA's Moon mission SMART-1 has produced the first detection from orbit of calcium on the lunar surface. By doing this, the instrument has taken a step towards answering the old question: did the Moon form from part of the Earth?

Scientists responsible for the D-CIXS instrument on SMART-1 are also announcing that they have detected aluminium, magnesium and silicon. "We have good maps of iron across the lunar surface. Now we can look forward to making maps of the other elements," says Manuel Grande of the University of Wales, Aberystwyth UK, and D-CIXS' Principal Investigator.

Knowing how to translate the D-CIXS orbital data into ‘ground truth’ has been helped by a cosmic coincidence. On 9 August 1976, the Russian spacecraft Luna 24 was launched. On 18 August it touched down in a region of the Moon known as Mare Crisium and returned a sample of the lunar soil to Earth.

In January 2005, SMART-1 was high above Mare Crisium when a giant explosion took place on the Sun. Scientists often dread these storms because they can damage spacecraft but, for the scientists responsible for D-CIXS, it was just what they needed.

The D-CIXS instrument depends on X-ray emission from the Sun to excite elements on the lunar surface, which then emit X-rays at characteristic wavelengths. D-CIXS collects these X-ray fingerprints and translates them into the abundance of each chemical element found on the surface of the Moon. Grande and his colleagues could relate the D-CIXS Mare Crisium results to the laboratory analysis of the Russian lunar samples.

They found that the calcium detected from orbit was in agreement with that found by Luna 24 on the surface of Mare Crisium. As SMART-1 flew on, it swept D-CIXS over the nearby highland regions. Calcium showed up here too, which was a surprise until the scientists looked at the data from another Russian moon mission, Luna 20. That lander had also found calcium back in the 1970s. This boosted the scientists’ confidence in the D-CIXS results.

Ever since American astronauts brought back samples of moonrock during the Apollo Moon landings of the late 1960s/early 1970s, planetary scientists have been struck by the broad similarity of the moonrocks and the rocks found deep in the Earth, in a region known as the mantle. This boosted the theory that the Moon formed from debris left over after the Earth was struck a glancing blow by a Mars-sized planet.

However, the more scientists looked at the details of the moonrock, the more discrepancies they found between them and the earthrocks. Most importantly, the isotopes found in the moonrocks did not agree with those found on Earth.

"The get-out clause is that the rocks returned by the Apollo missions represent only highly specific areas on the lunar surface and so may not be representative of the lunar surface in its entirety," says Grande; hence the need for D-CIXS and its data.

By measuring the abundance of several elements across the lunar surface, scientists can better constrain the contribution of material from the young Earth and its possible impactor to condense and form the Moon. Current models suggest that more came from the impactor than from Earth. Models of the Moon’s evolution and interior structure are necessary to translate the surface measurements into the Moon’s bulk composition.

D-CIXS was a small experimental device, only about the size of a toaster. ESA is now collaborating with India to fly an upgraded version on the Indian lunar probe Chandrayaan, due for launch in 2007–2008. It will map the chemistry of the lunar surface, including the other landing sites from where samples have been brought back to Earth. In this way it will show whether the Apollo and Russian landing sites were typical or special.

"From SMART-1 observations of previous landing sites we can compare orbital observations to the ground truth and expand from the local to global views of the Moon," says Bernard Foing, Project Scientist for SMART-1.

Then, perhaps planetary scientists can decide whether the Moon was indeed once part of the Earth.

Bernard Foing | alfa
Further information:
http://www.esa.int/SPECIALS/SMART-1/SEM1RHBUQPE_0.html

More articles from Physics and Astronomy:

nachricht Molecule flash mob
19.01.2017 | Technische Universität Wien

nachricht Magnetic moment of a single antiproton determined with greatest precision ever
19.01.2017 | Johannes Gutenberg-Universität Mainz

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>