May 2019: Seeing the Invisible

In the show this time, we talk to Syksy Räsänen about black holes as dark matter candidates and the future of scientific publishing, Hongming Tang rounds up the latest news, and we find out what we can see in the May night sky from Ian Morison, Haritina Mogosanu and Samuel Leske.

The News

This month in the news: the updated LIGO is back, TESS found its first Earth-sized exoplanet and Israel's plan for the Beresheeft 2 lunar lander.

Firstly, LIGO and Virgo have been updated and are now finding a black hole merger every week.

A little over a year ago, LIGO and Virgo triggered their upgrade procedures. After the upgrade, the instrument sensitivity of LIGO and Virgo increased by 40%. It was expected that this could possibly allow for weekly event detection. After the upgrade finished on April 1st, the observatory detected two probable gravitational wave events in two weeks.

LIGO and Virgo Collaborations sent the first public alert of an event they detected on April 8th and announced it 3 days later. On April 12th, the detectors caught a second signal. The two events were observed thanks to the collaboration between LIGO and Virgo Observatories. They are both believed to be the result of black holes merging. The announcement also marked that the new observation period O3 has begun and will last for about a year.

Now they are making their third observation run, a new public alert system was applied to benefit the community. The LIGO team will send out alerts when a detection is made, and observatories around the world then can point their telescopes at the sources. Multi-messenger astronomy would allow scientists to learn more about the cause of GW events, and also the dynamics behind them. The improved sensitivity also motivated scientists to study not only pulsar-pulsar merging and black hole- black hole merging, but also black hole-neutron star merging.

Also, the LIGO public alerts include a sky-map that provides the possible location of the source in the sky, the time when an event is detected, and what kind of the event it is believed to be. In the future, more detailed information on the candidates will be given once proper study of them is done. If you would like to hear about alerts in the future, you can download the alert app at Gravitational Wave Events iPhone App.

Next up, TESS just found its first Earth-sized exoplanet.

After the Kepler telescope's retirement, NASA's new planet-hunting telescope, TESS (Transiting Exoplanet Survey Satellite) just found its first Earth-sized exoplanet. This observation was taken in January this year, but it was not until April 15th they confirmed their status with follow-up observations and had the discovery published.

The newly discovered Earth-size planet is orbiting an orange main-sequence star called HD 21749. The solar system is about 53 light years from earth, and 70% the mass of the Sun. The Earth-size exoplanet is called HD 21947c, and the system also has a hot sub-Neptune planet called HD 21749b. The discovery of this sub-Neptune contributes to the TESS Level 1 Science Requirement of providing 50 transiting planets smaller than 4 times of earth radius with measured masses.

TESS was expected to discover about 300 Earth-like exoplanets in 2 years, which made this discovery significant. The idea behind TESS is to discover small Earth-size exoplanets, as its predecessor, the Kepler telescope, mostly found exoplanets with way larger sizes than Earth. Without a doubt, TESS will become a game-changing space telescope in the field of exoplanet studies in the next few years.

Finally, the plan of Israel's Beresheet2 lunar craft has been released.

Earlier last month, the Beresheet, Israel's moon lander, crashed into the Moon. The historic project is the first ever private funded moon landing project, and Israel became the fourth country attempted to land on the moon. The Beresheet lander started as an entry to the Google Lunar XPRIZE, and cost 200 million dollars to build, which made it one of the cheapest lunar landings in human history. The Google Lunar X Prize committee announced that it would award SpaceIL a 1 million dollar worth "Moonshot Award" for its achievements. As said by the XPRIZE founder Peter Diamandis, "SpaceIL's mission not only touched the Moon, it touches the lives and hearts of an entire world that was watching."

Fortunately, the failure of Beresheet is not the end of the project. Morris Kahn, Israeli billionaire entrepreneur and founder of SpaceIL, announced on April 13th that they are going to send the second lander to the moon, and use the failure of Beresheet as a building block. With the announcement of Beresheet2, SpaceIL might make Israel not only the fourth country to try to land on the moon, but the fourth to succeed.

Extended interview with Syksy Räsänen

Dr. Syksy Räsänen (University of Helsinki) came to us at an opportune moment - at the time of recording this interview, The Jodcast had just covered his guest post on the future of scientific publishing. We return to this subject in more depth, including the impact of the Plan S open access initiative and what role society publishing arms might take in the future. Beyond this, Syksy works on Higgs inflation, and how this might offer a pathway to miniature black holes as a dark matter candidate.

The Night Sky

Northern Hemisphere

Ian Morison tells us what we can see in the Northern Hemisphere night sky during May 2019.

The Planets

• Jupiter, starts the month shining at magnitude -2.5 which increases to to -2.6 as the month progresses. At the same time, its angular size increases from 43 to 46 arc seconds. As May begins it rises by midnight UT so will be due south around 3 am UT whilst at month's end it rises at ~9:30 pm UT so due south at ~01:30 UT. See the highlights fro when the Great Red Spot faces the Earth. Sadly it is heading towards the southernmost part of the ecliptic and currently lies in the southern part of Ophiuchus just above Scorpius so, as it crosses the meridian, it will only have an elevation of ~ 14 degrees. It lies just above the centre of the Milky Way. Atmospheric dispersion will thus take its toll and an atmospheric dispersion corrector would greatly help to improve our views of the giant planet.
  
  
• Saturn, shining with a magnitude increasing from +0.5 to +0.3 during the month, rises around midnight during the month so crosses the meridian just before dawn. Its disk is ~18 arc seconds across and its rings - which are still nicely tilted from the line of sight - spanning 40 arc seconds across. Morning twilight is the best time to observe it but, sadly, now in Sagittarius and lying on the southern side of the milky way, it is at the lowest point of the ecliptic and will only reach an elevation of ~10 degrees. As with Jupiter, an atmospheric dispersion corrector will help improve our view.
  
  
• Mercury, passes through superior conjunction (behind the Sun) on May 21st and will only be visible, low in the west-northwest, on the last few days of the month. One will need a very low horizon and binoculars could well be needed to reduce the Sun's background glare, but please do not use them until after the Sun has set.
  
  
• Mars, though fading from +1.6 to +1.8 magnitudes during the month, is still visible in Taurus in the south western sky after sunset lying half way between Betelgeuse, in Orion, and Capella, in Auriga. Mars sets some three hours after the Sun at the start of May (with an elevation as darkness falls of ~20 degrees) but less than two and a half hours by month's end. Its angular size falls from 4.2 arc seconds to less than 4 arc seconds during the month so one will not be able to spot any details on its salmon-pink surface.
  
  
• Venus, has a magnitude of -3.8 in May with its angular size reducing from 11.5 to 10.8 arc seconds during the month as it moves away from the Earth. However, at the same time, the percentage illuminated disk (its phase) increases from 88% to 92% - which is why the brightness remains constant at 3.8 magnitudes. It rises about an hour before the Sunbut its elevation is only ~4 degrees at sunrise so a very low horizon in the East is required and binoculars may well be needed to spot it through the Sun's glare - but please do not use them after the Sun has risen.
  
  

Highlights

• May 7th - after sunset: Mars lies above a thin crescent Moon. Given a low horizon looking towards the west after sunset one should, if clear, be able to spot Mars lying halfway between Betelgeuse and Capella above a very thin crescent Moon.
  
  
• April 12th - evening: The Moon in Leo Looking southwest in the evening a first quarter Moon will be seen lying close to Regulus in Leo.
  
  
• May 19th - early evening: Mars above M35 in Gemini. Looking west in early evening if clear, and using binoculars or a small telescope one could see Mars lying just above the open cluster, M35, in Gemini. Perhaps a last chance to see Mars at the very end of its apparition.
  
  
• May20th - midnight: Jupiter and the Moon. During the night of the 20 May, Jupiter will lie over to the right of the waning gibbous Moon.
  
  
• May 23rd - early morning: Saturn and the Moon. In the early Morning of the 23rd of May, Saturn will lie up to the right of the waning gibbous Moon.
  
  
• May 28th - around midnight: spot asteroid 1, Ceres. On the 28th May, Ceres is at its closest approach to Earth lying over to the right of Jupiter. It will have a magnitude of 7 so binoculars should enable you to spot it and the chart will help you find it. A planetarium program such as Stellarium will show you its position in the days before and after its closest approach. Ceres is the largest of the minor planets and is now classified as a 'Dwarf Planet'.
  
  

Southern Hemisphere

Haritina Mogosanu and Samuel Leske from the Carter Science Centre in New Zealand speak about the Southern Hemisphere night sky during May 2019.

• The rise of the Galaxy Kia Ora from New Zealand, we are here at Space Place at Carter Observatory holding Galactic Conversations from the heart of Wellington in the Southern Hemisphere, with the music of the amazing Rhian Sheehan, our Wellingtonian star composer. This month we have a very special guest, one of our own Milky Way Kiwi - from far across the Cook Strait and The Southern Alps, from Lake Tekapo - Holly. We have again instructions for looking up, we talk a little bit about the month of May, we look at what the Sun is up to, the Milky Way, Orion and Scorpius, we talk about the brightest stars visible and finally some favourite binocular and telescope objects, circumpolar objects and planets.
  
  
• A bit about May is the fifth month of the year in the Julian and Gregorian Calendars a month of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. It is named after the Greek goddess, Maia or Roman goddess of fertility, Bona Dea. Old English - Maius, Latin name - Maius mensis - Month of Maia, Old French - Mai. Maia was one of the Pleiades and the mother of Hermes. Maia is the daughter of Atlas and Pleione the Oceanid and is the oldest of the seven Pleiades. Because they were daughters of Atlas, they were also called the Atlantides. For the Romans, it embodied the concept of growth and as her name was thought to be related to the comparative adjective maius, maior "larger, greater". Convallaria majalis, the Lily of the Valley, one of my favourite flowers - is named after it and it is the flower of May in Europe.
  
  
• What's the Sun up to? The Sun rises from 7 to 7:30AM throughout the month and sets from around 5:30 to 5:00 PM. Beautiful and long nights are here.In May, the Sun transits first the zodiacal constellations of the Ram (Aries) and after 14th of May is in Taurus. This means that Scorpius is on the other side of the zodiacal wheel and visible starting after sunset.
  
  
• The Milky Way We are now looking towards the centre of our galaxy, which rises in the South East just after sunset and reaches meridian after 3 AM at the beginning of the month and 2 am towards the end.
  
  
• Bright stars in the Milky Way Starting from the West after sunset is Betelegeuse, then in zig-zag to the North is Procyon, the Little Dog alpha star. Zig-zagging again is Sirius, and Adhara, in the Big Dog, and Suhail al Muhlif and Avior in Vela, the beautiful stars of the Southern Cross, the two pointers, Alpha and Beta Centauri then later on in the night after the centre of the Milky Way rises, is Antares and Shaula in Scorpius, Nunki in Sagittarius and last but not least, after midnight, Altair and last but not least, Vega grazing the northern horizon.
  
  
• Orion and Scorpius Orion is very close to Taurus and it will sink further towards the horizon as the month progresses. Enjoy it while it lasts, for the rest of this month.
  
  
• Bright stars on the ecliptic Then Regulus in Leo (which is extremely close to the ecliptic) then Spica, the blue giant in Virgo, Zubenelgenubi, another star grazing the ecliptic and Zubeneschamali just beneath it. Zubenelgenubi means the northern claw and Zubeneschamali the southern claw, alluding to these two stars that have been the claws of Scorpius before they were chopped off and turned into the current constellation of Libra. They are followed by Antares which is the last very bright star visible on the ecliptic before sunrise.
  
  
• Circumpolar Objects to New Zealand The beautiful Southern Cross and the pointers are high in the sky. Gacrux and Acrux are crossing the meridian around 10 PM at the beginning of the month and just after 8PM at the end of it. Omega Centauri is in a great position to observe, as well as Musca, Vela, Carina and their Diamond Cross, and False Cross and the Large Magellanic Cloud and its Tarantula Nebula.
  
  
• Binocular Objects in May Binoculars come in many shapes and forms, a great size for stargazing is 7 x 50 or 10 x 50. The first number is a measure of power, it means how much these binoculars magnify, in this case the 7 and the 10. The second number is the diameter of the objective (the big lenses at the front) in millimetres, in this case the 50. I really like binoculars, they are my favourite aids to observing the night sky because they are light, you can take them easily with you on trips, they don't really require assembly and disassembly, no polar alignment, and visually are better than telescopes! With a tripod attached they are truly magnificent. Comets and some open star clusters are sometimes better observed with binoculars. We have two eyes, so binocular views are more spectacular in many regards than telescopic, because our brains interpret what we see, binoculars give depth of view as they engage both eyes in the process.
  There are a few great objects that you could admire in binoculars. On the ecliptic, M44 (the Praesepe) is an open cluster in Cancer. Known as the beehive, the open cluster swarms with stars. It's really fuzzy when you look at it with the naked eye and binoculars reveal a beautiful lace of stars. Praesepes are as far as 577 light years and estimated to be about 730 million years old with an average magnitude of 3.5. Also in Cancer, M37, is another open cluster, one of the oldest known, almost 3.2 billion years.
  You can get a map and look for all these objects. Or, if everything else fails, simply take your binoculars and swipe the Milky Way from one edge to the other. You might not figure out exactly which objects you are looking at but you would definitely find amazing sights, especially in the region close to Carina. You will find there IC2602, NGC3114, NGC353, NGC2516 that are all open clusters then in Crux NGC4755 which is another open cluster, NGC2451 in Puppis, and IC2391 in Vela. Lower down, Omega Centauri, is a globular cluster in Centaurus and in Scorpius, there are the Butterfly Cluster, M7 open cluster and NGC6231 open cluster.
  
  
• Telescope Objects in May A fantastic night in central Wellington where the Large Magellanic Cloud is only visible with averted vision, still, not bad for a capital city. We looked at the Southern Beehive NGC 2516, Gem Cluster NGC 3293, Southern Pleiades IC 2602, Wishing Well NGC 3532, Jewel Box NGC 4755, Omicron Velorum IC 2391, Omega Centauri NGC 5139, Alpha Centauri and Acrux, Tarantula NGC 2070.
  
  
• Planets Jupiter is in the sky just after 7:30 followed by Saturn two hours later and Venus is in the morning sky.
  
  
• Clear skies from New Zealand.
  
  

Odds and Ends

Shaking things up this episode, we hear about the first recorded "Marsquake". On April 6th NASA's InSight lander measured this expected phenomenon which was among its key science goals. Unlike Earth, Mars does not have tectonic plates; however, seismic activity can still occur as a consequence of stress caused by the slow cooling of the red planet. This had been expected for some time, and similar effects have been measured on the moon previously, but this is the first time seismic tremors have been measured on another planet. This was a weak quake, however if further stronger Marsquakes are detected it is the hope of the scientists working on the project to begin analysis of the interior structure of Mars.

The LHCb collaboration found a new source of matter-antimatter symmetry in the charm quark sector in the form violation of CP (Charge conjugation and Parity) symmetry. This shows that we perhaps haven't found all of the possible symmetry violations possible in Nature. The amount discovered is still not enough to explain why the Universe is made of matter and not equal amounts of both matter and antimatter, but indicates that there may be much more asymmetry we haven't found yet out there!

We discuss the first astrophysical detection of the helium hydride molecular ion (HeH⁺) in interstellar space, thought to be the earliest type of molecule to form in the Universe. Using SOFIA, the Stratospheric Observatory for Infrared Astronomy, astronomers spotted the signature of this molecule in planetary nebula NGC 7027, confirming a key aspect of our understanding of the Universe's evolution. More information can be found in the SOFIA release and the published paper (Güsten et al. in Nature, open access version on arXiv).

Show Credits