Our sun is ever-changing, and a satellite called
the Solar Dynamics Observatory has a front-row seat.
On February 11, 2010, we launched the Solar Dynamics
Observatory, also known as SDO. SDO keeps a constant eye on the sun, helping us
track everything from sunspots to solar flares to other types of space weather
that can have an impact on Earth.
After seven years in space, SDO has had a chance to do what few
other satellites have been able to do – watch the sun for the majority of a
solar cycle in 11 types of light.
The sun’s activity rises and falls in a pattern that lasts
about 11 years on average. This is called the solar cycle.
Solar activity can influence Earth. For
instance, it’s behind one of Earth’s most dazzling natural events – the aurora.
One of the most common triggers of the aurora is
a type of space weather called a coronal mass ejection, which is a billion-ton
cloud of magnetic solar material expelled into space at around a million miles
When these clouds collide with Earth’s magnetic field, they
can rattle it, sending particles down into the atmosphere and triggering the
auroras. These events can also cause satellite damage and power grid strain in
The sun is in a declining activity phase, so coronal mass
ejections will be less common over the next few years, as will another one of
the main indicators of solar activity – sunspots.
Sunspots are created by twisted knots of magnetic field. Solar
material in these tangled regions is slightly cooler than the surrounding areas,
making them appear dark in visible light.
The tangled magnetic field that creates sunspots also causes
most solar activity, so more sunspots means more solar activity, and vice
versa. Humans have been able to track the solar cycle by counting sunspots
since the 17th century.
The peak of the sun’s activity for this cycle,
called solar maximum, was in 2014.
Now, we’re heading towards the lowest solar
activity for this solar cycle, also known as solar minimum. As solar activity
declines, the number of sunspots decreases. We sometimes go several days
without a single visible sunspot.
But there’s much more to the story than sunspots
– SDO also watches the sun in a type of light called extreme ultraviolet. This
type of light is invisible to human eyes and is blocked by our atmosphere, so
we can only see the sun this way with satellites.
Extreme ultraviolet light reveals different layers of the
sun’s atmosphere, helping scientists connect the dots between the sunspots that
appear in visible light and the space weather that impacts us here on Earth.
SDO keeps an eye on the sun 24/7, and you can see near real-time
images of the sun in 11 types of light at sdo.gsfc.nasa.gov/data.
There is a bicycle light on the market that substantially increases the side visibility and clearly identifies the cyclist. It is called the Revolights Bike Lighting System, and it is mounted on the bicycle wheels with the help of special hardware. These are actually LED ring lights which ensure 360° visibility for bikes thus increasing cyclists’ safety. And they are perfectly legal. Men’s Journal called them “the best bike lighting system in the world”.
20 Out Of This World Facts About The Universe That Will Sweep You Off Your Feet
We’ve compiled a list of the 20 most incredible facts about the universe you will ever come across. The infinite expanse of stars and galaxies are riddled with mysteries which leading scientists and experts are yet to explore. In their quest to unearth the hidden secret of the universe, startling facts and information have emerged - 20 of which we’ve featured below.
1. When you look into the night sky, you are looking back in time.
When we gaze at stars in the night sky, we are actually looking into the past. This happens because light emitted from a star has to travels many light years ahead to actually become visible to our eyes. For example, Orion is 640 light-years away, so the light left the star around 1370 is what we are seeing now.
2. The Hubble telescope allows us to look back billions of years into the past
NASA releases some incredible images of space, from time to time, and it’s made possible with The Hubble Telescope. Here’s an image which is a collection of 10,000 images captured by The Hubble.
3. You can watch the Big Bang on your television
Cosmic background radiation is an after effect of the Big Bang, the event that allegedly gave birth to the universe. This can actually be seen on television where the old fuzzy noise we saw contains 1% of the same radiation.
4. There’s a giant cloud of alcohol in Sagittarius B
Sagittarius B, is a huge cloud of vinyl alcohol whizzing in space near the Milky Way. It’s important as it leaves crucial information for scientists about how early life forms originated in space.
5. There’s a planet-sized diamond in Centaurus named after a Beatles song
A planet , made completely of diamond, which has been called Lucy by scientists after the Beatles song, “Lucy in the Sky with Diamonds,” can be found 50 light years away in Centaurus and weighs in a mind boggling 10 billion-trillion-trillion carats.
6. It takes 225 million years for our Sun to travel around the galaxy
While our planets in the solar system circumnavigate the Sun, the star itself it on a orbit around the Milky Way. And if we’re counting in humans years, it takes 225 million years to complete the journey.
7. Our solar system’s biggest mountain is on Mars
The tallest mountain in our solar system is Olympus Mons, located on Mars. It’s calculated to be three times taller than Everest, spanning 600 kilometers across and 26 kilometers in height.
8. Uranus spins on its side, with some rather strange results
Uranus is not just unique because of its strange spinning, but the consequences of that effect results in 42 consecutive years of summer sunlight followed by another 42 consecutive winter darkness.
9. A year on Venus is shorter than its day
Venus is the slowest rotating planet in our solar system - it takes longer to finish a rotation on its axis than orbit the entire Sun!
10. Neutron stars are the fastest spinning objects known in the universe
The fastest spinning known pulsar, a neutron star which emits a radiation beam as light, cycles on a whopping 70,000 km per hour speed.
11. A spoonful of a neutron star weighs about a billion ton
Neutron stars are unimaginably dense, in fact one spoonful of one such star would weigh around a billion tons!
12. The Voyager 1 spacecraft is the most distant human-made object from Earth
In 1977, the Voyager 1 and Voyager 2 were released into space as an ambitious project and are still cruising the outskirts of our galaxy and maybe beyond to help us explore space even further.
13. Voyager 1 captured the most distant photograph of Earth
The same spacecraft, Voyager 1, took the most distant photograph of Earth: Voyager 1 took a shot of the Earth from the far reaches of space in 1990, and the small speck at the end of the image that is the world we’re living on right now became known as the Pale Blue Dot. Astronomer Carl Sagan noted,“From this distant vantage point, the Earth might not seem of any particular interest. But for us, it’s different. Consider again that dot. That’s here. That’s home. That’s us.”
14. Scientists are looking for evidence of extraterrestrial life on Earth
One of the most exciting mysteries of the universe is a quest to find aliens, or as termed by scientists a project called The Search for Extra-Terrestrial Intelligence (SETI), where they are pulling n all data about extraterrestrial life on other planets through evidence they have at their hands.
15. It is estimated there are 400 billion stars in our galaxy
Our own Sun is one of 400 billion others, some astoundingly larger, some smaller, in the Milky Way alone.
16. There could be 500 million planets capable of supporting life in our galaxy
“Goldilocks Planets” are habitable planets which fall into a specific zone around the star to make life sustainable on it. Many factors come into play to get this perfect distance such as temperature, atmospheric content, water, chemical compounds on the surface etc.
17. There are probably more than 170 billion galaxies in the observable universe
Based on extensive calculations, using data from the Hubble Telescope and as far as it can see into space, there’s a probable 170 billion galaxies besides our own Milky Way.
18. There could be an infinite number of universes
Speculative theories in advanced branches of science such as mathematics, quantum mechanics and astrophysics have summed up that we could be living in a “multiverse”- a convergence of an infinite number of universes.
19. The human brain is the most complex object in the known universe
Our brain is a blueprint for the most complex network in the universe, with over a hundred billion neurons and quadrillion connections- this system isn’t even the tip of the iceberg which we know about what our brains have the potential to achieve.
20. We are all made of stardust
Carl Sagan beautifully summarises this fact, “The nitrogen in our DNA, the calcium in our teeth, the iron in our blood, the carbon in our apple pies were made in the interiors of collapsing stars. We are made of starstuff.” In fact, every element on Earth transpired from a burning heart of a star.