No, we shouldn’t get too excited by the prospect that an Earth-like exoplanet circles the star nearest to us. Earth-like it may be, but make no mistake, Centauri b, that orbits red dwarf star Proxima Centauri, is not like Earth. For one thing, the planet is so close to its host star, it is tidally locked. This means it does not rotate on its axis as Earth does.
Therefore it is perpetually day time on one side of the side of the planet, while the other hemisphere is forever cloaked in darkness. One side would be rather warm, the other quite chilly. Only the border between the two, a veritable twilight zone, might be a little Earth-like. On that basis then, it may not be too bad…
There will be three different climate zones. The side always facing its star will be consistently sun-baked, receiving scorching, direct sunlight without ever getting a break from it. Similarly, the side facing away from the star will experience eternal night, and should be dark and frozen, but with spectacular views of the Universe. The border between the night and day sides – a “ring” around the planet – will experience an eternal dawn/sunset, with perhaps the most Earth-like conditions.
US astronaut Jeff Williams has spent five hundred and thirty-four days in space, during the course of his career. That includes a one hundred and seventy-two day stint aboard the International Space Station (ISS), as part of Expedition 47/48. He had been aboard the ISS for two previous expeditions. All up, that’s quite some time to be away from Earth.
The closest star to Earth is Proxima Centauri, a red dwarf that may, or may not, be part of the Alpha Centuari binary star system. If Proxima Centauri were found to be gravitationally bound to the binary star, then Alpha Centuari would become known as a trinary, or triple, star system.
But in what may prove to be the most exciting find to date, the German weekly Der Spiegel announced recently that astronomers have discovered an Earth-like planet orbiting Proxima Centauri, just 4.25 light-years away. Yes, in what is an apparent trifecta, this newly-discovered exoplanet is Earth-like, orbits within its sun’s habitable zone, and is within our reach. But is this too good to be true?
As an aside. With the Sun halfway through its ten billion year lifespan, we’ll be on the look out for a new home eventually, and it’s thought that relocating to a planet orbiting a red dwarf might be a good move. Red dwarf stars live for trillions of years, so our descendants wouldn’t need to think about moving again for a long, long, time.
If a habitable planet were found to be orbiting Proxima Centauri, might it one day become our new residence?
The Mars Reconnaissance Orbiter (MRO) has been in orbit around the red planet since March 2006, where it has been taking photos of the surface ever since. Recently NASA released just over one thousand of these images, taken in the last few months.
I think its fair to say the photos reveal a planet with an incredibly diverse surface. A case in point has to be both of these photos. The top picture is of a region near the North Pole. The second is of an area in the Southern Highlands. More images can be seen here.
Gorgeous galaxies and stunning stars make up this selection of pictures from the shortlisted entries for this year’s Insight Astronomy Photographer of the Year award. The winners will be announced on 15 September, and an exhibition of the winning images will be will be displayed in a free exhibition at the Royal Observatory Greenwich’s Astronomy Centre from 17 September.
Having spent five years travelling to Jupiter, via the scenic route, NASA’s space probe Juno, will, next week, place itself in a polar orbit around the solar system’s largest planet, and spend the next eighteen months learning more about Jupiter’s formation, composition, and its gravitational and magnetic fields.
At the end of its mission, Juno will be sent into Jupiter’s atmosphere, to ensure its destruction, lest it end up crash landing on, and contaminating, Europa, a Jovian moon that some scientists think may host marine life of some sort.
Even if you don’t want to go there yourself – it’s cold, you’d need to live underground, mail can takes years to get through, and so on – you can help with the effort to explore Mars, by pinning up these promotional posters, encouraging others to emigrate to the red planet.
The solar system is host to eight regular planets, any number of dwarf planets, and now, possibly, an exoplanet. That’s if the planetary body, known as Planet 9, that is said to orbit on the far fringes of the solar system, can be shown to have originated elsewhere, something mathematical modelling suggests is possible.
Through a computer-simulated study, astronomers at Lund University in Sweden show that it is highly likely that the so-called Planet 9 is an exoplanet. This would make it the first exoplanet to be discovered inside our own solar system. The theory is that our sun, in its youth some 4.5 billion years ago, stole Planet 9 from its original star.
It’s one thing to lose your job, but to lose your job in a place you cannot possibly leave, is another matter all together. This is the predicament that an explorer of Mars – who was sent to the red planet on a one way, no return trip ever, sort of undertaking – finds himself in. Thus you have the premise for Fired on Mars, a short film by Nick Vokey and Nate Sherman.