Solar-Terrestrial Sciences

A close-up journey to the Sun: The Parker Solar Probe Mission

Athanasios Papaioannou October 24, 2018

Artist’s concept of the Parker Solar Probe spacecraft approaching the sun. Credit: NASA/Johns Hopkins APL/Steve Gribben

Almost two months ago, in August 12, 2018 Parker Solar Probe (PSP) launched by NASA on a Delta IV Heavy rocket from Cape Canaveral, Florida. This is a long-awaited mission from the Heliospheric community. The first to explore the Sun within distances of ~0.167 AU (or 25 million kilometers) at its perihelia. Its ancestors were the successful Helios -A and -B spacecraft, a pair of probes launched in ...[Read More]

Cosmogenic Radionuclides – The quest of studying the solar activity of thousands of years

Athanasios Papaioannou September 18, 2018

Figure 1: Sketch of the processes involved in order to model the atmospheric production of the cosmogenic radionuclides. Courtesy K. Herbst

Thanks to the invention of the Neutron Monitor in 1948 and multiple spacecraft which monitor the cosmic ray environment since 1970’s we now have a constant record of the solar activity over almost 70 years. Information prior to this space era, however, are rare and take us back in time only to the late 1930s, when ionization chambers have been introduced. This of course allows us only a narr ...[Read More]

SunPy: a Python solar data analysis environment

Kamalam August 16, 2018

Introduction For many years now we know that our star the Sun influences the Earth in many different ways, via the total solar irradiance, solar energetic particles and coronal mass ejections. Understanding the influence of the Sun on the Earth requires many different types of measurements. For example, NASA’s Solar Dynamics Observatory (SDO) spacecraft, produces over 1 terabyte of data per day (P ...[Read More]

Jaime de la Cruz Rodriguez – ERC success in the field of solar physics

Kamalam July 17, 2018

Coronal Heating Problem is one of the Sun’s unsolved mysteries where the corona is heated to over a million degrees and scientists have not figured out where the energy is coming from. Dr Jaime de la Cruz Rodriguez is tackling this 70 year old puzzle by first understanding the layer of the Sun below the corona – the chromosphere. He is awarded the prestigious starting grant by the Euro ...[Read More]

The average magnetic field and polar current system (AMPS) model

Jone Peter Reistad June 15, 2018

Example of field aligned (red/blue) currents from both polar regions from the AMPS model. Grey pins represent the full horizontal current vector. The plot was made with the following input to the model: Solar Wind velocity: 350 km/s, IMF Bz: -8 nT, IMF By: -8 nT, dipole tilt angle: 20 degrees, F10.7: 80 sfu.

In this month’s post, Karl Magnus Laundal explains a newly developed empirical model for the full high latitude current system of the Earth’s ionosphere, AMPS (Average Magnetic field and Polar Current System). The model is available and documented in python code, published under the acronym pyAMPS. The community is invited to download and explore the electric currents and magentic fiel ...[Read More]

Prof. Ilya Usoskin – A discussion with an inquiry mind

Athanasios Papaioannou May 16, 2018

In Ancient Greece, the Sun was believed to be a god named Helios, who drove his shining carriage pulled by a quadriga along a dangerous and unpaved path through the sky. This was probably the first model of the Sun. Nowadays, we not only have a somewhat better theory but also know that, even during the Ancient Greek era, the Sun was not exactly like in this picture (from http://www.theoi.com/Titan/Helios.html)

In the May issue of the Life of a Scientist we have the pleasure to talk to Prof. Ilya Usoskin from the Univeristy of Oulu, Finland. Among numerous things, he is the head of the Oulu Cosmic Ray station and receipent of this year’s Julius Bartels EGU Medal; a decision that was based: “on his contributions to the understanding of the heliosphere, long-term changes in the solar activity ...[Read More]

Report from the 2018 EGU General Assembly

Jone Peter Reistad April 20, 2018

EGU venue. Credit: EGU/Stephanie McClellan

Last week the 2018 General Assembly were held in Vienna. Gathering 15 075 scientists from 106 countries, this is the most important EGU event throughout the year. Summarizing what happened during the week is an impossible task, as a meeting like this is way more than the 666 individual sessions convened and the 11 128 posters presented during the week. However, in this post I will point to some of ...[Read More]

Cosmic rays – messengers from space

Athanasios Papaioannou March 19, 2018

Artistic representation of cosmic rays entering the Earth's atmosphere (Credit: Asimmetrie/INFN).

Cosmic rays (CRs), are not actually rays, but highly energetic charged particles of extraterrestrial origin. The life cycle of a cosmic ray particle starts with its birth at some point in the Universe, its travel at nearly the speed of light and finally with its death ( e.g. at a detector). These highly energetic particles strike our planet from all directions and thus provide a constant backgroun ...[Read More]

Social media response to geomagnetic activity

Jone Peter Reistad February 15, 2018

Daily averaged geomagnetic activity level and daily count of posts related to Aurora from Twitter during March 2017

Social media platforms offer every person with internet access the possibility to share content of various kind. The recent increase in social media use globally give birth to new tools and insights, from a different perspective. The size of, and the global nature of the user driven social media, makes one expect it to include information also about geomagnetic activity related to posts of visual ...[Read More]

How do we study the magnetosphere?

Jone Peter Reistad January 15, 2018

The Sun-Earh system. Credit: NASA

Our closest star, the Sun, is constantly emitting hot gas in all directions as its upper atmosphere, the corona, expands. This is known as the Solar Wind, also carrying with it an embedded magnetic field, the Interplanetary Magnetic Field (IMF). The IMF originates at the Sun and forms an enormous spiral throughout the solar system as the solar wind escapes radially, while the magnetic field-line ...[Read More]