Does the Moon have a molten core?

Monday 1st August 2011
Submitted by mstaple
JOHN MORRIS, BY EMAIL

This was one of the questions the Apollo missions were tasked with resolving over 40 years ago, but only now is the answer becoming clear. The astronauts placed seismometers on the lunar surface to detect ‘moonquakes’, in the hope that analysis of how the shockwaves travelled through the Moon would reveal what lay at its core. The seismometers were finally switched off in 1977, and scientists have been trying to make sense of the data ever since.

One major problem has been finding the signals of deep moonquakes among the ‘noise’ of other events, including meteor impacts. Using computers to clean up the data, a team led by Dr Renee Weber of NASA’s Marshall Space Flight Center in Huntsville, Alabama, has now found evidence that the Moon has a core very similar to that of the Earth, with a solid innermost region, and a molten outer core.

GOT A QUESTION?

Scratching your head over a burning scientific conundrum? Submit your question and we'll get our esteemed panel of experts to answer it for you.

 

Does a queen bee ever sting?
previous qanda Article
What causes cramp?
next qanda Article
Q&A Tabs

Lobsters and other shellfish have harmful bacteria naturally present in their flesh. Once the lobster is dead, these bacteria can rapidly multiply and release toxins that may not be destroyed by...

It depends on the temperature of the water. In cold water, the bacterial action that causes a body to bloat with gas may be so slowed that the body stays on the seabed. The skin will absorb water...

Phlegm is the mucous secretion of the respiratory passages. The cilia cells that line these passages are continually driving the phlegm upward to the throat, where it triggers the swallow reflex...

 When a nuclear bomb explodes on Earth, the huge release of radiation triggers the rapid expansion of air around it, causing the intense blast wave that wreaks so much destruction. In the...

Ordinary glass absorbs 97 per cent of the UVB rays that cause sunburn and some skin cancers, and 37 per cent of the less harmful UVA radiation. This translates to a protection of about SPF30, so...

All female mammals have a clitoris, the sole purpose of which is to react to sexual stimulation, and presumably this stimulation has evolved to be pleasurable for most species. But establishing...

To create a sound, we have to set matter - whether it's a gas like air, a liquid or even a solid material - in regular motion, creating a wave of specific frequencies, which we hear as a sound of...

Mirrors don’t reverse left and right either – that’s just our interpretation of what happens. Your reflection in the mirror is actually reversed front to back – if you have...

Discovered by an American student named Gary Flandro in the mid-1960s, the slingshot manoeuvre usually involves spacecraft briefly 'coat-tailing' a planet orbiting the Sun, extracting some of the...

The ice disappears because the wind blows away water molecules that have evaporated or 'sublimed' from the ice, so the ice slowly shrinks in size. The molecules that escape are those with the...