Great mysteries of the Universe

[jw5]

Are we alone?​

In this artist's impression, the planetary system around the red dwarf, Gliese 581, is pictured showing what astronomers believe is another as yet unnamed Earth-like planet found outside our solar system, a planet that could have water running on its surface. And it's a lot nearer to us, a mere 20.5 light-years away, in the constellation Libra. Suddenly, the potential for extraterrestrial life seems a lot more real.

 

[jw5]

Red dwarf​

A red dwarf is the most common star type in the Universe. It's also the smallest and coolest kind. Not one red dwarf is visible from Earth, even though they account for 50 of the 60 nearest stars to our planet, and make up three-quarters of the stars in the Milky Way.

 

[jw5]

Titan​

Titan is the largest moon of Saturn and the second-largest natural satellite in the solar system. Titan is the only moon wrapped in a thick atmosphere and has a surface of rock-hard water ice. Intriguingly, it also likely has a liquid water ocean beneath its surface. Image: NASA/JPL-Caltech/Space Science Institute

 

[jw5]

Dark clouds​

A dark cloud in space is a cloud of gas and dust that blocks light from the regions of space behind it. Pictured are newborn stars peeking out from beneath their natal blanket of dust in this dynamic image of the Rho Ophiuchi dark cloud from NASA's Spitzer Space Telescope. Located near the constellations Scorpius and Ophiuchus, the nebula is about 407 light-years away from Earth.

 

[jw5]

Sunspots​

Sunspots are caused by disturbances in the Sun's magnetic field welling up to the photosphere, the Sun's visible 'surface.' The number of sunspots on our Sun typically ebbs and flows, with each sunspot lasting a few days to a few months, and the total number peaking every 11 years.

 

[MaximiLian]

Please watch ze Ancient Aliens series for answers

 

[jw5]

Cosmic rays​

Cosmic rays are high-energy protons and atomic nuclei that zap through space at nearly the speed of light. They most likely originate from the Sun, from outside of the solar system in our own galaxy, and from distant galaxies. This ionizing radiation is harmless to us because it bounces off the Earth's atmosphere. However, cosmic rays have been blamed for electronic circuit problems and data crashes in satellites and other machinery. Image: NASA

 

[jw5]

Solar flare​

Similarly, a solar flare is an intense eruption of electromagnetic radiation in the Sun's atmosphere. The phenomenon is associated with sunspots. Flares are our solar system's largest explosive events, and can last from minutes to hours.

 

[jw5]

Callisto​

Callisto is possibly the most highly cratered body in the solar system. It's the second-largest moon of Jupiter, after Ganymede, and thought to be a long dead world, with hardly any geologic activity on its surface. It's one of the oldest landscapes in the Cosmos, dated back to at least four billion years. Image: NASA

 

[jw5]

Space roar​

A mysterious screen of extra-loud radio noise permeates the Cosmos. Scientists discovered this when they launched an instrument called the Absolute Radiometer for Cosmology, Astrophysics, and Diffuse Emission (ARCADE), fixed to a huge balloon that was sent to space. ARCADE was designed to pick up radio waves from distant stars, but the signal received was much louder than expected, something cosmologists term "space roar." Image: NASA

 

[jw5]

Fermi Bubble​

Discovered by cosmologists as recently as 2010, Fermi Bubbles are massive, mysterious structures that emanate from the Milky Way center and extend roughly 20,000 light-years above and below the galactic plane. They emit high-energy gamma rays and X-rays, invisible to the naked eye.

 

[jw5]

Magnetic field of the Moon​

When Apollo astronauts brought back Moon rock, scientists were surprised to learn that some of them were magnetic. Researchers believe the magnetism may be a relic of a 193-km-wide (120 mi) asteroid that collided with the Moon's southern pole about 4.5 billion years ago, scattering magnetic material across some parts of the lunar surface.

 

[jw5]

Pulsar​

A pulsar is a highly-magnetized rotating neutron star so named because it emits beams of electromagnetic radiation out of its magnetic poles at regular intervals. But no one is quite sure why. Even more puzzling is that occasionally these stars stop pulsing.

 

[jw5]

Miranda​

The 11th of Uranus' moons and the fifth largest, Miranda has a surface unlike anything in the solar system. Its broken, haphazard terrain features the Verona Rupes range—10,058 m (33,000 ft) tall and thought to be the highest cliffs in the solar system. They are visible at the bottom of this photograph. Image: NASA/JPL-Caltech

 

[jw5]

Atlas​

Saturn's flying saucer moon, Atlas is another solar system oddball. An inner satellite discovered in 1980, Atlas appears like a deep space UFO. Image: NASA/Jet Propulsion Lab-Caltech/Space Science Institute

 

[jw5]

Phobos​

Phobos, the inner and larger of Mars' two moons (the other being Deimos), is thought by scientists to be in a "death spiral" in that it's slowly orbiting toward the surface of Mars. The natural satellite is named after the Greek god Phobos, the personification of fear and panic, and the origin of the world phobia. Image: NASA/JPL-Caltech/University of Arizona

 

[jw5]

Is space infinite?​

The current width of the observable Universe is about 90 billion light-years. But what lies beyond? The short answer is cosmologists aren't sure. Presumably, there's a bunch of other random stars and galaxies. If the Universe is perfectly geometrically flat, then it can be infinite. If it's curved, like Earth's surface, then it has finite volume. But no one knows.