Institute of Astronomy PUBLIC OPEN EVENING outreach — 17 January 2017 — A

Clean water ice hiding just below TONIGHT’S SPEAKER the surface of Mars The talk schedule for can be viewed this term at:

Matt Bothwell The biggest galaxy in the Universe?

Our weekly welcome ELCOME to our weekly public Wopen evenings for the 2017/18 season. Each night there will be a half-hour talk which begins promptly Erosion on Mars has uncovered large, steep cross-sections of clean, subterranean ice. In this at 7.15pm: tonight Matt Bothwell will false color image captured by NASA’s HiRISE camera, one of eight recently discovered stripes be giving us his talk The biggest appears dark blue against the Martian terrain. Credit: NASA/JPL/Uni. Of Arizona/USGS galaxy in the Universe? The talk is followed by an oppor- IT’S GOOD news for future Martian scientists have discovered this in no tunity to observe if (and only if!) the www.ast.cam.ac.uk/public/public_observing/current colonists – NASA has just discovered less than eight different places across weather is clear. The IoA’s historical plenty of easy-to-access water just Mars, in both hemispheres. Northumberland and Thorrowgood under Mars’s surface. The new photographs were taken by Astronomers have known for ‘HiRISE’, a powerful camera attached telescopes, along with our modern decades that water exists on Mars, but to NASA’s Mars Reconnaissance Orbit- 16-inch telescope, will be open just how easy it is to get at (and use) er, and the purity of the hidden water for observations. In addition, the has long been a mystery. Water that is was confirmed by taking spectra. Cambridge Astronomical Association buried too deep, or is too sparse, will The new findings may lead to many will provide a floorshow outdoors on be of little use to any future Martian exciting possibilities: the new findings the Observatory lawns, relaying live visitors. The difficulty has been the suggest that we might be able to take images from their telescopes and rocks and dirt on Mars’ surface. Our ‘ice cores’, which will allow us to study providing a commentary. If we’re un- robotic Martian landers (such as Curi- Martian climate change much as we lucky and it’s cloudy, we’ll offer you a osity) can dig down a few centimetres, do on Earth. And of course the exist- conciliatory cup of tea after the talk and we can use radar scanning tech- ence of a source of pure water, easily (with perhaps some more astro-in- nology to reach far below the surface. accessible from the surface, will be formation in the lecture theatre for But what lies in between these depths very exciting news to anyone planning – just a few metres below the surface – for human visitors: “It’s looking more those who want to stay on). is relatively unknown. encouraging that water ice could be Luckily, a very down-to-Earth available at depths shallow enough process has come to our aid: erosion. that could be used as resources for By wearing away the surface of cliffs, human missions to Mars,” says Angel If you have any questions, suggestions or erosion has revealed large deposits of Abbud-Madrid, the director of the comments about the IoA Open Evenings nearly pure water ice lying just one or Center for Space Resources at the please contact Carolin Crawford at two metres below Mars’ surface. And Colorado School of Mines. [email protected] or Matt Bothwell at this isn’t just in one isolated spot – [email protected].

@cambridge_astro facebook.com/InstituteOfAstronomy 2 — IOA PUBLIC OPEN EVENING — 17 January 2017

Amateur astronomers team up to Mystery Radio find multi-planetary system Bursts From Space A NEW discovery may have shed light on Fast Radio Bursts, one of the most perplexing astronomical mysteries of the last decade. Since their discovery in 2007, This artist concept shows K2-138, the first astronomers have witnessed several multi-planet system discovered by citizen of these powerful, short-lived radio scientists. Credit: NASA/JPL-Caltech bursts, which generally last just a few milliseconds. Many explana- tions have been offered, including FOR the first time ever, a team of ama- “Zooniverse”, and using data taken by exploding stars, collapsing black teur astronomers has discovered a dis- NASA’s ‘Kepler’ space telescope. Kepler holes, or alien messages (of course!). tant star system. The newly-discovered works by measuring the brightness of These bursts come from billions planetary system is called “K2-138”, stars. The tell-tale sign of exoplanets of light years away, and can be and is 620 light-years away. K2-138 is are small dips in brightness, caused hundreds of millions of times more made up of 5 or 6 rocky planets orbiting by the planets passing in front of their powerful than our Sun. And we are around an orange dwarf star about half star. Kepler has currently looked at lucky that they are so distant: a Fast the mass of our Sun. All of the planets nearly 300,000 stars – a lot of data Radio Burst even on the other side are in very close orbits around their to sort through! That’s where the of our own galaxy could play havoc parent star, taking between 2.4 and 12.8 Exoplanet Explorers come in to help. with our phone communications. days to complete one orbit. The planets Founded in 2017, the group has attract- Now, new observations taken are rocky ‘super-Earths’, scaled-up ed thousands of citizen scientists to with the Arecibo Observatory and versions of our rocky home planet. Bad their cause, helping to sort through the the Green Bank Telescope may have news though for anyone hoping for masses of data collected by Kepler. provided us a clue to the origin of habitable planets: their proximity to Another batch of Kepler data has these extreme events. A new Burst, their parent star means they are almost recently been made available for the known as FRB 121102, was studied definitely too hot for life to survive. Exoplanet Explorers to search through and astronomers found something The system was discovered by a – fingers crossed for some exciting surprising: hidden within the radio group called the Exoplanet Explorers, planetary systems in store for us. waves was the tell-tale fingerprint of working as part of the online project a strong magnetic field. Whatever is causing these bursts, it must be very Ingredients for life found in meteorites magnetic. This narrows down the search for the origin of the bursts: a WHERE did we come from? The origin ents include carbon, nitrogen, oxygen, supermassive black hole seems most of life on Earth has fascinated scientists alongside amino acids (the building likely, though the aftermath of a for centuries. And a new analysis of two blocks of our proteins). supernova is also a candidate. meteorites might have got us one step By studying the material trapped closed to the answer. within the meteorites, scientists have The two meteorites, called Mona- also been able to estimate where the hans and Zag, originally crashed to meteorites originally came from. It is Earth in 1998 (in Texas and Morocco, likely that the organic matter within respectively). A new X-ray analysis of the meteorites came from an ocean the two meteorites has revealed an world in the early Solar System – possi- abundance of liquid water, along with bly the dwarf planet Ceres. the organic ingredients needed for life. Though this new finding isn’t proof “This is really the first time we have of life beyond Earth, it is an exciting found abundant organic matter also snapshot of the Solar System’s deep associated with liquid water that is past – “like a fly in amber”, according to One of the salt crystals sampled from the Zag really crucial to the origin of life and the scientists. And it shows that the in- meteorite which contain organic matter. the origin of complex organic com- gredients required for life were plentiful Credit: Queenie Chan/The Open University pounds in space”, said lead researcher in the early days of our Solar System. Dr. Queenie Chan. “We’re looking at the “Everything leads to the conclusion Joke of the Week organic ingredients that can lead to the that the origin of life is really possible origin of life.” These organic ingredi- elsewhere,” says Chan. Orion’s Belt is a big waist of space.