Facts About Our Sun!

The Sun is the star at the centre of the Solar System
It is by far the most important source of energy for life on Earth.
Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth.
Its mass is about 330,000 times that of Earth;
Its age is about 4.6billion years
Its temperature at Centre is 〖1.57*10〗^7 K and at Photosphere is about 5,772 K
it accounts for about 99.86% of the total mass of the Solar System.
Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon and iron
The structure of the Sun contains the following layers:
Core – the innermost 20–25% of the Sun's radius, where temperature and pressure are sufficient for nuclear fusion to occur. Hydrogen fuses into helium (which cannot itself be fused at this point in the Sun's life). The fusion process releases energy, and the core gradually becomes enriched in helium.
Radiative zone – Convection cannot occur until much nearer the surface of the Sun. Therefore, between about 20–25% of the radius, and 70% of the radius, there is a "radiative zone" in which energy transfer occurs by means of radiation (photons) rather than by convection.
Tachocline – the boundary region between the radiative and convective zones.
Convective zone – Between about 70% of the Sun's radius and a point close to the visible surface, the Sun is cool and diffuse enough for convection to occur, and this becomes the primary means of outward heat transfer, similar to weather cells which form in the earth's atmosphere.
Because the Sun is a gaseous object, it does not have a clearly defined surface; its visible parts are usually divided into a "photosphere" and "atmosphere":
Photosphere – the deepest part of the Sun which we can directly observe with visible light.
Atmosphere – a gaseous "halo" surrounding the Sun, comprising the chromosphere, solar transition region, corona and heliosphere. These can be seen when the main part of the Sun is hidden, for example, during a solar eclipse.

Missions to sun
Genesis
Genesis was a NASA sample-return probe that collected a sample of solar wind particles and returned them to Earth for analysis.
Genesis was launched on August 8, 2001,
The mission's primary science objectives were:[8]
To obtain precise solar isotopic abundances of ions in the solar wind, as essentially no data having a precision sufficient for solving planetary science problems are available;
To obtain greatly improved solar elemental abundances by factor of 3–10 in accuracy over what is in the literature;
To provide a reservoir of solar matter for 21st century science to be archived similarly as the lunar samples.
Genesis was a Discovery-class mission of the NASA Jet Propulsion Laboratory (JPL) at the California Institute of Technology. The spacecraft was designed and built by Lockheed Martin Space Systems at a total mission cost of US$264 million.
Most of the Genesis collectors continuously sampled all of the solar wind which the spacecraft encountered (the "bulk solar wind"). However, the spacecraft also carried three arrays of collectors which were deployed when specific "regimes" (fast, slow, coronal mass ejections) of solar wind were encountered, as determined by the electron and ion monitors on board. These deployable collector arrays were designed to provide data to test the hypothesis that the rock-forming elements keep their relative proportions throughout the processes which form the solar wind.
Genesis cruised to the Earth-Sun L1 then performed a Lissajous orbit insertion maneuver, entering an elliptical orbit about L1 on November 16, 2001. Genesis exposed its collector arrays on December 3, and began collecting solar wind particles. The collection process ended after 850 days, on April 1, 2004, with the spacecraft completing five halo loops around L1.[16] Genesis began its return to Earth on April 22, 2004
Following completion of the collection phase, the collector arrays were stowed in a sample return capsule, and the spacecraft returned to Earth. As the capsule was approaching Earth and at the first stages of re-entry, all appeared well.
The sample return capsule crash-landed in Utah on September 8, 2004, after a design flaw prevented the deployment of its drogue parachute. The crash contaminated many of the sample collectors. Although most were damaged, some of the collectors were successfully recovered


Credits: https://en.wikipedia.org/wiki/Genesis_(spacecraft)
Solar and Heliospheric Observatory
The Solar and Heliospheric Observatory (SOHO) is a spacecraft built by a European industrial consortium led by Matra Marconi Space (now Airbus Defence and Space) that was launched on a Lockheed Martin Atlas II AS launch vehicle on December 2, 1995, to study the Sun. It has also discovered over 4,000 comets.[2][3] It began normal operations in May 1996.
The three main scientific objectives of SOHO are:
Investigation of the outer layer of the Sun, which consists of the chromosphere, transition region, and the corona. The instruments CDS, EIT, LASCO, SUMER, SWAN, and UVCS are used for this solar atmosphere remote sensing.
Making observations of solar wind and associated phenomena in the vicinity of L1. CELIAS and COSTEP are used for "in situ" solar wind observations.
Probing the interior structure of the Sun. GOLF, MDI, and VIRGO are used for helioseismology.
In normal operation, the spacecraft transmits a continuous 200 kbit/s data stream of photographs and other measurements via the NASA Deep Space Network of ground stations. SOHO's data about solar activity are used to predict coronal mass ejection (CME) arrival times at earth, so electrical grids and satellites can be protected from their damaging effects. CMEs directed toward the earth may produce geomagnetic storms, which in turn produce geomagnetically induced currents, in the most extreme cases creating black-outs, etc.
In 2003, ESA reported the failure of the antenna Y-axis stepper motor, necessary for pointing the high-gain antenna and allowing the downlink of high-rate data. At the time, it was thought that the antenna anomaly might cause two- to three-week data-blackouts every three months.
The SOHO Payload Module (PLM) consists of twelve instruments, each capable of independent or coordinated observation of the Sun or parts of the Sun, and some spacecraft components. The instruments are:[10][11]
Coronal Diagnostic Spectrometer (CDS), which measures density, temperature and flows in the corona.
Charge Element and Isotope Analysis System (CELIAS), which studies the ion composition of the solar wind.
Comprehensive SupraThermal and Energetic Particle analyser collaboration (COSTEP), which studies the ion and electron composition of the solar wind. COSTEP and ERNE are sometimes referred to together as the COSTEP-ERNE Particle Analyzer Collaboration (CEPAC).
Extreme ultraviolet Imaging Telescope (EIT), which studies the low coronal structure and activity.
Energetic and Relativistic Nuclei and Electron experiment (ERNE), which studies the ion and electron composition of the solar wind. (See note above in COSTEP entry.)
Global Oscillations at Low Frequencies (GOLF), which measures velocity variations of the whole solar disk to explore the core of the Sun.
Large Angle and Spectrometric Coronagraph (LASCO), which studies the structure and evolution of the corona by creating an artificial solar eclipse.
Michelson Doppler Imager (MDI), which measures velocity and magnetic fields in the photosphere to learn about the convection zone which forms the outer layer of the interior of the Sun and about the magnetic fields which control the structure of the corona. Solar Ultraviolet Measurement of Emitted Radiation (SUMER), which measures plasma flows, temperature, and density in the corona.
Solar Wind Anisotropies (SWAN), which uses telescopes sensitive to a characteristic wavelength of hydrogen to measure the solar wind mass flux, map the density of the heliosphere, and observe the large-scale structure of the solar wind streams.
UltraViolet Coronagraph Spectrometer (UVCS), which measures density and temperature in the corona.
Variability of solar IRradiance and Gravity Oscillations (VIRGO)