Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Meteorites record past solar activity

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:

More articles from Physics and Astronomy:

nachricht Sharpening the X-ray view of the nanocosm
23.03.2018 | Changchun Institute of Optics, Fine Mechanics and Physics

nachricht Drug or duplicate?
23.03.2018 | Fraunhofer-Institut für Angewandte Festkörperphysik IAF

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: Space observation with radar to secure Germany's space infrastructure

Satellites in near-Earth orbit are at risk due to the steady increase in space debris. But their mission in the areas of telecommunications, navigation or weather forecasts is essential for society. Fraunhofer FHR therefore develops radar-based systems which allow the detection, tracking and cataloging of even the smallest particles of debris. Satellite operators who have access to our data are in a better position to plan evasive maneuvers and prevent destructive collisions. From April, 25-29 2018, Fraunhofer FHR and its partners will exhibit the complementary radar systems TIRA and GESTRA as well as the latest radar techniques for space observation across three stands at the ILA Berlin.

The "traffic situation" in space is very tense: the Earth is currently being orbited not only by countless satellites but also by a large volume of space...

Im Focus: Researchers Discover New Anti-Cancer Protein

An international team of researchers has discovered a new anti-cancer protein. The protein, called LHPP, prevents the uncontrolled proliferation of cancer cells in the liver. The researchers led by Prof. Michael N. Hall from the Biozentrum, University of Basel, report in “Nature” that LHPP can also serve as a biomarker for the diagnosis and prognosis of liver cancer.

The incidence of liver cancer, also known as hepatocellular carcinoma, is steadily increasing. In the last twenty years, the number of cases has almost doubled...

Im Focus: Researchers at Fraunhofer monitor re-entry of Chinese space station Tiangong-1

In just a few weeks from now, the Chinese space station Tiangong-1 will re-enter the Earth's atmosphere where it will to a large extent burn up. It is possible that some debris will reach the Earth's surface. Tiangong-1 is orbiting the Earth uncontrolled at a speed of approx. 29,000 km/h.Currently the prognosis relating to the time of impact currently lies within a window of several days. The scientists at Fraunhofer FHR have already been monitoring Tiangong-1 for a number of weeks with their TIRA system, one of the most powerful space observation radars in the world, with a view to supporting the German Space Situational Awareness Center and the ESA with their re-entry forecasts.

Following the loss of radio contact with Tiangong-1 in 2016 and due to the low orbital height, it is now inevitable that the Chinese space station will...

Im Focus: Alliance „OLED Licht Forum“ – Key partner for OLED lighting solutions

Fraunhofer Institute for Organic Electronics, Electron Beam and Plasma Technology FEP, provider of research and development services for OLED lighting solutions, announces the founding of the “OLED Licht Forum” and presents latest OLED design and lighting solutions during light+building, from March 18th – 23rd, 2018 in Frankfurt a.M./Germany, at booth no. F91 in Hall 4.0.

They are united in their passion for OLED (organic light emitting diodes) lighting with all of its unique facets and application possibilities. Thus experts in...

Im Focus: Mars' oceans formed early, possibly aided by massive volcanic eruptions

Oceans formed before Tharsis and evolved together, shaping climate history of Mars

A new scenario seeking to explain how Mars' putative oceans came and went over the last 4 billion years implies that the oceans formed several hundred million...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

New solar solutions for sustainable buildings and cities

23.03.2018 | Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

Latest News

For graphite pellets, just add elbow grease

23.03.2018 | Materials Sciences

Unique communication strategy discovered in stem cell pathway controlling plant growth

23.03.2018 | Agricultural and Forestry Science

Sharpening the X-ray view of the nanocosm

23.03.2018 | Physics and Astronomy

Science & Research
Overview of more VideoLinks >>>