Help Shape the Future of Space Exploration

Join The Planetary Society Now  arrow.png

Join our eNewsletter for updates & action alerts

    Please leave this field empty

Our Sun

All the planets, moons, and smaller things in the solar system are just dust, compared to the star that they orbit; the Sun contains 99.9% of the mass of the solar system. We think of it as our source of light, but it doesn't just emit photons. The solar wind blasts fast-moving electrons, protons, and highly ionized atoms in all directions, a constant stream punctuated by ferocious coronal mass ejections. The solar wind carries with it a magnetic field wound into a tight spiral by the Sun's rotation.

The solar wind pushes outward against the interstellar medium, penning the solar system inside a bubble called the "heliosphere" that's at least 200 AU across. The twin Voyager spacecraft are now probing the heliosphere's edges. Closer to home, a fleet of spacecraft monitors the space weather generated by the Sun, warning us of its effects on Earth, from the benevolent (aurorae) to the potentially disastrous (irradiation of astronauts and damage to communications satellites and power grids).  Currently operating solar space observatories include ACE, GGS, WIND, Hinode, PICARD, RHESSI, SOHO, SDO, Solar Monitoring Observatory, and STEREO.

Latest Blog Entries about the Sun, Heliosphere, and Space Weather

Missions to a Star

Posted by Bill Dunford on 2014/02/17 02:45 CST | 2 comments

Upcoming deep space missions will venture right to the heart of the Solar System.

Read More »

Mega Hemorrhaging Total Lunar Eclipse Sept 27-28, 2015

Posted by Bruce Betts on 2015/09/24 08:25 CDT | 1 comment

There will be a spectacular total lunar eclipse on the night of Sept. 27-28, 2015, a newly dubbed Mega Hemorrhaging Eclipse. Here is info on what lunar eclipses are and how to observe the eclipse.

Read More »

Mars conjunction today: Cool SOHO/SDO video

Posted by Emily Lakdawalla on 2011/02/04 11:41 CST

Today Mars made its closest approach to the Sun -- as seen from Earth, that is. Why is this important?

Read More »

Making eclipse magic

Posted by Emily Lakdawalla on 2012/05/16 09:55 CDT | 2 comments

How to enjoy a solar eclipse with your kids, making shadow magic with a pinhole viewer.

Read More »

Intro Astronomy Class 1: Tour of the Solar System

Posted by Bruce Betts on 2014/02/11 05:53 CST | 1 comment

Take a tour of the Solar System in the video of class 1 of Bruce Betts' Introduction to Planetary Science and Astronomy class.

Read More »

Items 21 - 25 of 41  Previous123456789Next
Facebook Twitter Email RSS AddThis

Essential Advocacy

Our Advocacy Program provides each Society member a voice in the process.

Funding is critical. The more we have, the more effective we can be, translating into more missions, more science, and more exploration.



Beyond The Horizon, There's More To Explore!

Become a member of The Planetary Society and together we will create the future of space exploration.

Join Us

Space in Images

Pretty pictures and
awe-inspiring science.

See More

Join The Planetary Society

Let’s explore the cosmos together!

Become a Member

Connect With Us

Facebook, Twitter, YouTube and more…
Continue the conversation with our online community!