As of 2019, only five space probes are leaving the solar system: Pioneer 10, Pioneer 11, Voyager 1, Voyager 2 and New Horizons. The Voyagers already left the solar system and entered the interstellar space (Voyager 1 on August 25, 2012, and Voyager 2 on November 5, 2018. The others also will leave the heliosphere Notes 1 and reach the interstellar space in a few years.
All of these spacecraft are launched by NASA.
Continue reading Five space probes leaving the solar system (for now)
The speed of light is the Universal speed limit – nothing can travel faster than light. In the vacuum (commonly denoted c), its exact value is 299,792,458 meters per second (around 186,000 miles per second). In other words, if you could travel at the speed of light, you could go around the Earth 7.5 times in one second.
Continue reading Speed of Light – See how torturously slow it is
Launched by NASA on September 5, 1977, to study the outer solar system, the Voyager 1 is the furthest human-made object from Earth. As of January 10, 2019, the space probe is more than 13,491,481,615 miles (21,712,434,988 km) away from our home planet. It is also moving away at a speed of 38,026.77 mph (61,198.15 km/h) relative to the Sun. But, thanks to NASA’s Deep Space Network (DSN) Notes 1, we can still communicate with it (also with its sister, Voyager 2). But how far can Voyager 1 go before we lose communication?
The video published by the Primal Space channel below looks at how we communicate with Voyager and when it will eventually stop receiving our signals.
Continue reading Watch: How far can Voyager 1 go before we lose contact?
We only see one side of the moon, because it is tidally locked to the planet Earth (tidal locking the situation when an object’s orbital period matches its rotational period). What if the Earth was tidally locked to the Sun?
Continue reading What if the Earth was tidally locked to the Sun?
A beautiful Ultima Thule image, taken by the Long Range Reconnaissance Imager (LORRI) aboard NASA’s New Horizons spacecraft in original context against a starry background (i.e., not zoomed in).
Continue reading Ultima Thule image against a starry background
NASA Goddard Planetary Scientist James O’ Donoghue created a nice animation showing the sidereal days and axial tilts of the solar system planets.
Continue reading The sidereal days and axial tilts of the Planets
Researchers discovered the farthest known object in our solar system and named it “Farout” (far-out-there). It is about 120 times farther than Earth is from the Sun (120 AU Notes 1). For comparison, the most distant planet, Neptune is about 30 AU from the Sun. At its most distant, once upon a time the ninth planet, now a dwarf planet, Pluto, can be 49 AU (7.29 billion km, or 4.53 billion miles) from the Sun. Currently, Pluto is at about 34 AU, making Farout more than three-and-a-half times more distant than the Solar System’s most-famous dwarf planet.
Continue reading Farout: the most-distant body ever observed in Solar System
Previously I posted articles titled “If The Moon Were Only 1 Pixel – A Tediously Accurate Map Of The Solar System” and “A Scale Model Of Solar System Drawn In The Desert And The Result Is Stunning”. Since the human brain cannot deal with the really large numbers, these articles provide amazing ways to understand how big actually our Solar System is.
Now, in his YouTube channel, The Science Asylum, physicist Nick Lucid provides yet another scale model of the solar system. A very nice video conceptualizing how mind-bogglingly big our solar system (and space) is.
Continue reading Watch: Yet Another Scale Model of the Solar System
This size comparison of the Sun and the planets in our solar system is going around frequently, but it’s still amazing to see it. Created by the San Francisco-based artist Roberto Ziche,
Continue reading Size comparison of the Sun and the planets
The Moon is completely uninhabitable and lifeless today – a dusty, dry rock. It has no atmosphere, there is no liquid water on the surface, and, maybe the most important, it has no magnetosphere to protect its surface from solar wind and cosmic radiation. But, according to a new study published in Astrobiology, it may have looked quite different around four billion years ago: its surface was not as dry as it is today, and conditions to support simple life on the Moon existed twice during the early years.
Continue reading Life on the Moon? New study suggests there was a habitability window 4 billion years ago