In the show this time, we talk to Chris Flynn about Observing Fast Radio Bursts, plus using the Moon to study climate change and Gaia to weigh the Milky Way, George Bendo rounds up the latest news, and we find out what we can see in the January night sky from Ian Morison, Haritina Mogosanu, and Samuel Leske.
In the news this month: the 50th anniversary of the Apollo 8 mission, the recent New Horizons fly-by, and the Chinese Moon landing.
First, the 21st of December marked the 50th anniversary of the launch of the Apollo 8 mission. Apollo 8 did not land people on the Moon, but it was an important step to an eventual Moon landing.
The mission was a general part of the Space Race in the 1960s, where the United States and the Soviet Union vied to demonstrate which country could produce the grandest achievements in space exploration. The Soviet Union had been the first nation to orbit a satellite around the Earth in 1957 and the first to send a person into space in 1961. Earlier in 1968, the Soviet Union had been the first to launch unmanned missions that had returned from the Moon. These missions were seen as preparation steps by the Soviet Union to send a manned mission to the Moon. NASA had been planning to use Apollo 8 to test their lunar spacecraft in orbit around the Earth, but plans were changed to send the spacecraft to the Moon and back.
The mission was an overall success. Frank Borman, Jim Lovell, and William Anders became the first people to travel to another body in space. They also took multiple photos of both the Moon and the Earth, including a very famous Earthrise photos from when the orbiter had passed around the far side of the Moon. The lessons from the mission were applied to later missions, including Apollo 11, which was the first to land people on the Moon.
Next in the news, on the 1st of January, the New Horizons spacecraft flew by a Kuiper Belt object given the official name of 2014 MU69 but nicknamed Ultima Thule. The Kuiper Belt is a collection of icy bodies found in orbit just outside the orbit of Neptune and is thought to be the source of many short-period comets like Halley's Comet. Pluto, which New Horizons flew by in 2015, is the largest of the Kuiper Belt objects. Ultima Thule is thought to be more representative.
Ultima Thule was revealed to consist of two spheroidal bodies of slightly different sizes that combined have a width of about 31 kilometers across. The two separate parts of the object are thought to have come together very gently during the very early stages of the Solar System. Since then, the object has changed relatively little. Because the density of objects in the Kuiper Belt is very low, Ultima Thule has not been affected by impacts or gravitational interactions with other objects. Because Ultima Thule is very far from the Sun, the ices have not melted or sublimated over time. Additionally, because Ultima Thule is so small, it has not undergone any type of geological or geothermal activity as seen on planets. Hence, Ultima Thule is similar to what objects from the early formation of the Solar System look like. However, the surface object has been exposed to large numbers of cosmic rays over time, and this has transformed the ices on the surface of the object into a very dark coating of organic material with a reddish hue. While the first images have been released to the general public, more scientific analyses are likely to be published on the data in the upcoming months and years.
Finally, on the 3rd of January, the Chinese probe Chang'e-4 landed on the far side of the Moon. This was the first science mission to the surface of far side of the Moon. Most other spacecraft have landed on the near side of the Moon, although a few other spacecraft have crashed onto the far side either deliberately or accidentally. This also marks the first time that China's space agency has been able to do something that no other nation's space agency has done.
The landing is not just a symbolic achievement. The far side of the Moon is geologically different from the near side. The surface is more heavily cratered, and the far side has fewer of the smooth maria areas. The probe actually landed within the Von Karman Crater, which is one of the few smooth locations on the far side. A scientific analysis of the surface may reveal differences in the chemistry or history of the surface compared to the near side of the Moon.
Interview with Chris Flynn
In this interview Chris Flynn talks about observing Fast Radio Bursts, plus using the Moon to study climate change and Gaia to weigh the Milky Way.
The Night Sky
Ian Morison tells us what we can see in the northern hemisphere's night sky during January 2019.
- Jupiter.Jupiter starts the month rising around 5 a.m., and brightens from magnitude -1.9 to -1.9 as the month progresses whilst its angular size increases slightly from 31.8 to 33.6 arc seconds. The highlights show how it combines with Venus to give us some wonderful views in the East before dawn.
- Saturn.Saturn passes behind the Sun on the 2nd of January so will not be visible in the pre-dawn eastern sky until around the third week of the month shining with a magnitude of +0.6. With a disk of ~15 arc seconds across and with rings spanning over twice this, it will rise one and a half hours before the Sun by month's end.
- Mercury.Mercury might just be glimpsed in the first few days of the month very low in the southeast just before sunrise shining at magnitude -0.4. Binoculars could well be needed as this reduces the background glare, but please do not use them after the Sun has risen.
- Mars.Mars, though fading from +0.5 to +0.9 magnitudes during the month remains prominent in the southern sky after sunset at an elevation of ~36 degrees, increasing to 41 degrees during January as it moves north-eastwards across the constellation of Pisces. (If only it could have been at this elevation when at closest approach last year!) Its angular size falls from 7.5 arc seconds to 6 arc seconds during the month so one will not be able to spot any details on its salmon-pink surface.
- Venus.Venus reaches greatest elongation west some 47 degrees away from the Sun on January 6th so dominates the eastern sky rising some 3 hours before the Sun. It begins January with a dazzling magnitude of -4.6. Its angular size reduces from 26.3 to 19.4 arc seconds during the month as it moves away from the Earth but, at the same time, the percentage illuminated disk (its phase) increases from 47% to 62% - which is why the brightness only reduces from -4.6 to -4.3 magnitudes. See the highlight above when it lies close to Jupiter.
- January 3rd - before dawn: Jupiter below a very thin crescent Moon.
- Around the 6th of January (with no Moon in the sky): find M31 - The Andromeda Galaxy - and perhaps M33 in Triangulum.Around new Moon (6th Jan) - and away from towns and cities - you may also be able to spot M33, the third largest galaxy after M31 and our own galaxy in our Local Group of galaxies. It is a face on spiral and its surface brightness is pretty low so a dark, transparent sky will be needed to spot it using binoculars (8x40 or, preferably, 10x50). Follow the two stars back from M31 and continue in the same direction sweeping slowly as you go. It looks like a piece of tissue paper stuck on the sky just a bit brighter than the sky background. Good Hunting!
- January12th - evening: Mars above a waxing Moon.Looking south in the evening if clear, Mars will be seen lying above a waxing crescent Moon.
- January 21st - a Total Eclipse of the Moon.If clear in the hours before dawn, we should be able to see a Total Eclipse of the Moon as it moves through the Earth's shadow at times indicated on the chart. It will be fully eclipsed from 04:41 to 05:43. A nice photo opportunity.
- January 31st - just before dawn: a thin crescent Moon lies between Jupiter and Venus.If clear just before dawn, and given a low horizon towards the southeast, one should be able to see a thin waning crescent Moon lying between Jupiter (on its right) and Venus shining brightly to its left. A nice photo opportunity.
- January 13th and 26th evening: The Hyginus Rille.For some time a debate raged as to whether the craters on the Moon were caused by impacts or volcanic activity. We now know that virtually all were caused by impact, but it is thought that the Hyginus crater that lies at the centre of the Hyginus Rille may well be volcanic in origin. It is an 11 km wide rimless pit - in contrast to impact craters which have raised rims - and its close association with the rille of the same name associates it with internal lunar events. It can quite easily be seen to be surrounded by dark material. It is thought that an explosive release of dust and gas created a vacant space below so that the overlying surface collapsed into it so forming the crater.
- The Shining Ones.
- Kia Ora from New Zealand. Hi everyone, We are here at Space Place at Carter Observatory holding Galactic Conversations from the heart of Wellington in the Southern Hemisphere, my favourite place to be, with the music of the amazing Rhian Sheehan, our Wellingtonian star composer, and we are Haritina Mogosanu and Samuel Leske. Space Place is our historical astronomy icon here in New Zealand and we are located right at the heart of our capital city. And we are so lucky to be among the capital cities in the world from where you can still see the Milky Way.
- Summary. This time of the year we are looking straight into the edge of our galaxy, the Milky Way, as Orion is the main feature out there in the sky. While everyone in the Northern Hemisphere celebrates through the mid-winter festivities, here in the South we have the longest days and the shortest nights while roasting in sunshine. We have to wait all the way to 9 PM for the Sun to set. There is one planet visible with the naked eye in the early night sky, Mars. But if you are an early riser, you're in luck, all the other naked eye planets are in the morning sky. As for deep sky objects, the month is perfect for observing Orion and some of the objects from the Northern Hemisphere that sit below Orion in the Southern Sky, such as the fabulous Rosette Nebula and the elusive M74. Back to the south celestial region, we can still see the Magellanic Clouds and some awesome circumpolar objects, check out our videos on how to find them on Milky-Way. And did you know that this time of the year you can see the brightest, second brightest and third brightest star in the sky from here from Wellington? If you have a solar telescope you can admire a very quiet Sun. Almost no spots adorn the Sun but we will be watching it closely to see if any appear. (Do NOT look at the sun with a telescope, binoculars or even the naked eye without protection!) Watch for the Moon, it new on the first Sunday of the month, which means that's a good week for deep sky observations, and full on the third week, the 21st of January.
Haritina Mogosanu and Samuel Leske tell us what we can see in the southern hemisphere's night sky during January 2019.
Odds and Ends
|Interview:||Chris Flynn and Emma Alexander|
|Night sky:||Ian Morison, Haritina Mogosanu, and Samuel Leske|
|Presenters:||Emma Alexander, George Bendo, Naomi Asabre Frimpong, Samuel Leske, Ian Morison, Haritina Mogosanu, Michael Wright and Duncan Zerafa|
|Editors:||George Bendo and Tom Scragg|
|Segment Voice:||Iain McDonald|
|Website:||Naomi Asabre Frimpong and Stuart Lowe|
|Producer:||Naomi Asabre Frimpong|
|Cover art:||Apollo 8 launch CREDIT: NASA|