Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Meteorites record past solar activity

27.09.2006
Ilya Usoskin (Sodankylä; Geophysical Observatory, University of Oulu, Finland) and his colleagues have investigated the solar activity over the past centuries. Their study is to be published this week in Astronomy & Astrophysics Letters.

They compare the amount of Titanium 44 in nineteen meteorites that have fallen to the Earth over the past 240 years. Their work confirms that the solar activity has increased strongly during the 20th century. They also find that the Sun has been particularly active in the past few decades.


A sunspot the size of the Earth. Sunspots result from the solar magnetic activity. Credit: Max Planck Institute for Solar System Research, Dr. Vasily Zakharov. Image taken with the Swedish Solar Telescope on the island of La Palma.

I. Usoksin and his colleagues have used meteorites to reconstruct past solar activity. Studying the earlier activity of our Sun is one of the oldest astrophysical projects, as astronomers began recording the number of sunspots to trace the Sun's magnetic activity four hundred years ago.

The international team examined a set of nineteen meteorites whose dates of fall are precisely known, and measured the amount of radioactive isotope Titanium 44 in these meteorites. Titanium 44 is produced by the cosmic rays in the meteorites while they are outside the Earth’s atmosphere. After the meteorite has fallen, it stops producing this isotope. By measuring the Titanium 44 in these meteorites, they are able to determine the level of solar activity at the time the meteorite fell.

Past solar activity is reconstructed with this technique in an independent way, that is, one not affected by terrestrial effects. How high the solar activity was at a given epoch was previously known from measuring the concentration of cosmogenic isotopes produced at that time. But most of the isotopes found on the Earth – in Greenland and Antarctic ice sheets or in tree rings, for instance – are also affected by terrestrial processes, in these examples related to the Earth’s magnetic field and climate. Until now, reconstructing past solar activity was thus very uncertain. This is shown by how various reconstructions that were previously published differ from one other. In the new study to be published this week in Astronomy & Astrophysics Letters, the team shows that the Sun is currently particularly active compared to earlier centuries.

[1] The team includes N. Bhandary (Basic Sciences Research Institute, Ahmedabad, India), G.A. Kovaltsov (Ioffe Physical-technical Institute, St. Petersburg, Russia), S.K. Solanki (Max-Planck Institute for Solar System Research, Katlenburg-Lindau, Germany), C. Taricco (Istituto Nazionale di Fisica Nucleare, Torino, Italy) and I.G. Usoskin (University of Oulu, Finland).

Jennifer Martin | alfa
Further information:
http://www.obspm.fr
http://www.aanda.org/index.php?option=com_content&task=view&id=181&Itemid=42&lang=en

More articles from Physics and Astronomy:

nachricht APEX takes a glimpse into the heart of darkness
25.05.2018 | Max-Planck-Institut für Radioastronomie

nachricht First chip-scale broadband optical system that can sense molecules in the mid-IR
24.05.2018 | Columbia University School of Engineering and Applied Science

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: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>