One of the greatest mysteries that life on Earth holds is, “Are we alone?”
At NASA, we are working hard to answer this question. We’re scouring the universe, hunting down planets that could potentially support life. Thanks to ground-based and space-based telescopes, including Kepler and TESS, we’ve found more than 4,000 planets outside our solar system, which are called exoplanets. Our search for new planets is ongoing — but we’re also trying to identify which of the 4,000 already discovered could be habitable.
Unfortunately, we can’t see any of these planets up close. The closest exoplanet to our solar system orbits the closest star to Earth, Proxima Centauri, which is just over 4 light years away. With today’s technology, it would take a spacecraft 75,000 years to reach this planet, known as Proxima Centauri b.
How do we investigate a planet that we can’t see in detail and can’t get to? How do we figure out if it could support life?
This is where computer models come into play. First we take the information that we DO know about a far-off planet: its size, mass and distance from its star. Scientists can infer these things by watching the light from a star dip as a planet crosses in front of it, or by measuring the gravitational tugging on a star as a planet circles it.
We put these scant physical details into equations that comprise up to a million lines of computer code. The code instructs our Discover supercomputer to use our rules of nature to simulate global climate systems. Discover is made of thousands of computers packed in racks the size of vending machines that hum in a deafening chorus of data crunching. Day and night, they spit out 7 quadrillion calculations per second — and from those calculations, we paint a picture of an alien world.
While modeling work can’t tell us if any exoplanet is habitable or not, it can tell us whether a planet is in the range of candidates to follow up with more intensive observations.
One major goal of simulating climates is to identify the most promising planets to turn to with future technology, like the James Webb Space Telescope, so that scientists can use limited and expensive telescope time most efficiently.
Additionally, these simulations are helping scientists create a catalog of potential chemical signatures that they might detect in the atmospheres of distant worlds. Having such a database to draw from will help them quickly determine the type of planet they’re looking at and decide whether to keep observing or turn their telescopes elsewhere.
On this day, 12 November 1977, the first Reclaim The Night march took place in the UK in Leeds, York, Bristol, Manchester, Newcastle, Brighton and London. They were called by the Leeds Revolutionary Feminist Group, who were inspired by news of co-ordinated women-only ‘Take Back The Night’ marches against sexual harassment, held across towns and cities in West Germany on the 30th April 1977. This was particularly significant to women in the area because of the serial murders by Peter Sutcliffe, dubbed by the press as the ‘Yorkshire Ripper’, who sexually attacked and murdered thirteen women across Yorkshire between 1975 and 1980. Women in the area were angry that the police response to these murders seemed slow and that the press barely reported on them when it was mainly women involved in sex work who were murdered. But when a young female student was murdered, the press and the police seemed to take more notice. The police response was to tell women not to go out at night, effectively putting them under curfew. This was not a helpful suggestion for any women, those working late shifts or night shifts, or those involved in sex work who often had no choice about whether they went out at night or not. Despite the fact that the Ripper was known to be white, police used the opportunity of the investigation to harass Asian youths. Learn more about this in our podcast: https://workingclasshistory.com/2019/09/18/e28-29-asian-youth-movements-in-bradford/https://www.facebook.com/workingclasshistory/photos/a.296224173896073/1261401684044979/?type=3
