Helium-3 is a very special gas that costs about $2,000 per liter. Lancaster University has many bottles because the lab saved it when it was cheap. 'Our very wise predecessorspredecessors/ˈprɛdɪˌsɛsərz/L2前任；前辈People who held a position or did a job before the current person. stocked up,' says Dima Zmeev, a senior lecturer. This gas is used for quantumquantumL1与量子力学相关的Relating to quantum mechanics. computers and nuclear fusion. However, the main source today is from nuclear weapons, and there is not enough for future demand.
Because helium-3 is so rare, some companies want to get it from the moon. Moon dust may have higher concentrations of this gas. One company, Interlune, and another called Astrotech are planning to extractextract/ɪkˈstrækt/L2提取；提炼To take something out, especially using a process or effort. it. 'We've spent the last four years developing and testing technologies,' says Rob Meyerson, the CEO. They will need to process huge amounts of moon dust to get just one kilogram, which is a mountain-moving prospectprospect/ˈprɒspɛkt/L2前景；可能性The possibility or chance that something good will happen in the future..
There are also other possible sourcessources/ˈsɔːrsɪz/L2来源；出处Places, things, or people that provide something that is needed. of helium-3. Some scientists are looking for it in the Earth's crust, but the amount there is very low. For example, a company called Pulsar Helium is investigatinginvestigating/ɪnˈvɛstɪˌɡeɪtɪŋ/L2调查；研究Examining something carefully to find out the truth or learn more about it. a site in Minnesota. 'Minnesota is a lot easier to get to than the moon,' says a geochemist. If companies succeed, we will have more helium-3 for important science.
