The findings could help us understand the history of other bodies in our solar system
此些研究可能有助於人解,咱太系中,其他天的演程。
The history of our planet has been written, among other things, in the periodic reversal of its magnetic poles. Scientists at the Weizmann Institute of Science propose a new means of reading this historic record: in ice.
其他事一,咱行星的演程,一直被印於其磁的期性反中。以色列魏茨曼科研究所的科家提出了一,於冰中,取此演程之的新方法。
Their findings, which were recently reported in Earth and Planetary Science Letters, could lead to a refined probing ice cores and, in the future, might be applied to understanding the magnetic history of other bodies in our solar system, including Mars and Jupiter’s moon Europa.
他最近(2020年6月)表於《地球暨行星科事》期刊的研究,可能引出精探冰芯的方法,且在未可能被用解,我太系中,其他天的磁演程,包括火星及木星的星—巴星。
The idea for investigating a possible connection between ice and Earth’s magnetic history arose far from the source of the planet’s ice – on the sunny isle of Corsica, where Prof. Oded Aharonson of the Institute’s Earth and Planetary Sciences Department, was attending a conference on magnetism.
查研究冰地球的磁演程,一可能性的概念,非起自行星冰的源。魏茨曼科研究所地球暨行星科系教授,Oded Aharonson出席了,位於地中海、光普照之科西嘉上,行一有磁的。
More specifically, the researchers there were discussing the field known as paleo-magnetism, which is mostly studied through flakes magnetic minerals that have been trapped either in rocks or cores drilled through ocean sediments.
更具地,在那研究人了,主要是透一直被陷於岩石或穿海洋沉物之芯中,薄片磁性物行研究,被通古磁性的域。
Such particles get aligned with the Earth’s magnetic field at the time they are trapped in place, and even millions of years later, researchers can test their magnetic north-south alignment and understand the position of the Earth’s magnetic poles at that distant time.
粒子被陷於原地,它地球磁成一直,即使百年之後,研究人能它的南-北磁解地球磁,在那久期的位置。
The latter is what gave Aharonson the idea: If small amounts of magnetic materials could be sensed in ocean sediments, maybe they could also be found trapped in ice and measured. Some of the ice frozen in the glaciers in places like Greenland or Alaska is many millennia old and is layered like tree rings. Ice cores drilled through these are investigated for signs of such things as planetary warming or ice ages. Why not reversals in the magnetic field as well?
予Aharonson上述概念的是後者:在海洋沉物中,倘若能到少量磁性物,或也能量,被陷於冰中的它。一些於似格陵或阿拉斯加等地之冰川中的冰,有千年且如的年般,是分的。研究人查研究了,穿上述冰川之冰芯,行星暖或冰河期的此事象。何在此磁中,有反?
The first question that Aharonson and his student Yuval Grossman who led the project had to ask was whether it was possible that the process in which ice forms in regions near the poles could contain a detectable record of magnetic pole reversals.
的Aharonson及其生Yuval Grossman,必需疑的第一是,在靠近地之地,於冰形成的程中,是否可能具有磁反的可。
These randomly-spaced reversals have occurred throughout our planet’s history, fueled by the chaotic motion of the liquid iron dynamo deep in the planet’s core.
此些隔的反,在咱行星整演程中,曾生。是由行星核心深之液的紊所激起。
In banded rock formations and layered sediments, researchers measure the magnetic moment &nash; the magnetic north-south orientations – of the magnetic materials in these to reveal the magnetic moment of the Earth’s magnetic field at that time. The scientists thought such magnetic particles could be found in the dust that gets trapped, along with water ice, in glaciers and ice sheets.
在成岩及分的沉物中,研究人量了,於此些中磁性物的磁矩(磁的南-北方向),揭露在那期,地球磁的磁矩。此些科家,在同水冰,被陷於冰川及冰原中的埃中,能磁粒子。
The research team built an experimental setup to simulate ice formation such as that in polar glaciers, where dust particles in the atmosphere may even provide the nuclei around which snowflakes form.
研究建了一置,模如地冰川中,埃粒子於大中,甚至可能提供核心,供雪花形成的冰形成。
The researchers created artificial snowfall by finely grinding ice made from purified water, adding a bit of magnetic dust, and letting it fall though a very cold column that was exposed to a magnetic field, the latter having an orientation controlled by the scientists.
藉由精研磨,水成的冰,添加一磁性埃,然後使其通曝露於具有,由此些科家控制之磁、非常冷的柱子落下,此些研究人造了人工降雪。
By maintaining very cold temperatures – around 30 degrees Celsius below zero, they found they could generate miniature “ice cores” in which the snow and dust froze solidly into hard ice.
藉由持大零下30℃的冷度,他能形成,雪埃成硬冰的小型“冰芯”。
“If the dust is not affected by an external magnetic field, it will settle in random directions which will cancel each other out,” says Aharonson. “But if a portion of it gets oriented in a particular direction right before the particles freeze in place, the net magnetic moment will be detectible.”
Aharonson宣:「倘若埃不受外部磁影,在相互抵消的方向上,定下。不,倘若在此些粒子到位之前,一部分就朝向特定方向,磁矩是可的。」
To measure the magnetism of the “ice cores” they had created in the lab, the Weizmann scientists took them to Hebrew University in Jerusalem, to the lab of Prof. Ron Shaar, where a sensitive magnetometer installed there is able to measure the very slightest of magnetic moments. The team found a small, but definitely detectible magnetic moment that matched the magnetic fields applied to their ice samples.
了量他已,在室中,造之“冰芯”的磁性。魏茨曼科研究所的科家,此些冰芯到希伯大(位於耶路撒冷),Ron Shaar教授的室。安在那的敏磁力能量,最微小的磁矩。了,施加到其冰本之磁匹配的明可小磁矩。
“The Earth’s paleo-agnetic history has been studied from the rocky record; reading it in ice cores could reveal additional dimensions, or help assign accurate dates to the other findings in those cores,” says Aharonson. “And we know that the surfaces of Mars and large icy moons like Europa have been exposed to magnetic fields. It would be exciting to look for magnetic field reversals in ice sampled from other bodies in our solar system.”
Aharonson宣:「地球古磁性的演程,一直岩石的被研究。取在冰芯中的,可能揭露外的部分,或助精年代於,在那些芯中的其他研究。不他知,火星及如巴星之大冰冷星的表面,一直被暴露於磁中。在咱太其他天之冰中,找磁反是令人振的。」
“We’ve proved it is possible,” he adds. Aharonson has even proposed a research project for a future space mission involving ice core sampling on Mars, and he hopes that this demonstration of the feasibility of measuring such a core will advance the appeal of this proposal.
他附言:「我已是可能的。」Aharonson甚至已未涉及,於火星上集冰芯本的太空任,提出了一研究。他期盼,量此冰芯之可行性的,增此提的吸引力。
原文址:https://wis-wander.weizmann.ac.il/earth-sciences/magnetic-history-ice
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