A Standard Candle in the Dark

Show notes for Episode 192, April 7, 2014
Hosts: Paul, Rob C., Jesse
Title: A Standard Candle in the Dark
This week, we traversed the Solar System discussing a new way to age our own Moon, checking in on the “swimming pool” suspected by Cassini gravity measurements to exist beneath the south pole of Enceladus (satellite of Saturn) and finally meandering out to the realm of the Trans Neptunian Objects.  We then set sail for the gamma ray signatures in our own galaxy (dark matter anyone) before charging off to the distant shores of AGNs and the possible (and exciting) new standard candle method involving accretion disks and dust disks around massive central black holes.

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The Matt, Pat, and Paul Travelling Universe Show!

Show notes for Episode 190, March 24th 2014
Hosts: Paul, Pat, Matt (Guest)
Title: The Matt, Pat and Paul Traveling universe show!

Tonight’s show will feature some local devastation (on Jupiter from comet SL9) not to mention a quick summary of the changing appearance of nearly planets (gullies on Mars, volcanoes on Venus).  However, the real excitement is way back in the past with Matt Johnson (YorkU and Perimeter Institute) as we examine in some detail the announcement of the detection of B-mode polarization and its implications for inflation in the early universe and the Big Bang cosmology.

This week in space/astronomy history:
1. Comet Shoemaker Levy 9 March 24 1993 discovery.  It was a “rubble train” at this point, the most unusual comet that either Eugene (or Carolyn) Shoemaker or David Levy had ever seen.  Tidally disrupted by Jupiter in 1992, Comet SL9 (formerly D/1993 F2) would rain rocks into the Jovian atmosphere in a spectacular manner in July 1994.
2. March 24 1975 marked the end of the Mariner 10 mission, first mission to extensively map the planet Mercury.  A lack of onboard fuel to allow teh spacecraft to orient its radio antenna towards Earth finally closed off the scientific flow from Mariner 10.
3. Mercury RD-BD unmanned Mercury flight that COULD have flown Alan Shepard into a sub-orbital flight prior to Yuri Gagarin’s flight of April 12 1961.  However, the mission remained unmanned and flew successfully.
4. Birthday shoutout to Joseph Hooton Taylor, born March 29 1941.  Nobel Prize for work on pulsars, shared with Russell Hulse in 1980.  taylor is synonymous with pulsar research and the uses pulsars (rotating neutron stars) have in testing aspects of teh theory of relativity.
5. Christian Huygens discovered the largest moon of Saturn,  Titan in March 25 1655.

Guest:  Matt Johnson (of York University and the Perimeter Institute) will discuss with the YorkUniverse Team the announcement last Monday March 17 2014 of the B-mode polarization detection and its implications for the Inflation model of the Big Bang cosmology.
Matt intro:

  • Bachelor’s in Liberal Arts (Physics specialization) at Evergreen State College, Olympia Washington USA

  • PhD Physics at UC Santa Cruz

  • Postdoc at CalTech

  • Postdoc at Perimeter Institute

  • Assistant Professor at York University and Associate Faculty Member at Perimeter

Large gravitational wave signal in the CMBR is good news!  Other existing (and planned) instruments can check if it’s real, and if so, study it in detail to gain new information about inflation. Will the B-mode polarization be found at other wavelengths?  If not, does this suggest the interpretation of gravity waves as the cause of the B mode polarization needs to be revisited or indeed discarded?  Pat is suggesting that new observations will cast doubt on the current interpretation of the B mode observations.  A $10 bet is “on” with Matt!  Stay tuned.

News:
1. Active volcanoes on Venus?  New data from ESA’s Venus Express suggests that 3 recent volcanic eruptions may have occurred.  While the notion of Venusian volcanism dates back to the Pioneer Venus days of the late 1970s, no definitive proof has yet been established.  venus is tough to observe even with orbiting spaceprobes.  Smrekar et al from JPL have measured 3 “hot spots” on the Venusian surface that they conclude are very recent.  While the article is soon to be published in Nature, the  data from Visible and Infrared Thermal Imaging Spectrometer (VIRTIS), is very suggestive of three eruptions last year.  Sulphur dioxide measurements are often cited as evidence of such eruptions but that is not considered definitive.
2. Next crew to launch to the ISS March 25, 5:17 PM EDT.  Expedition 39, despite the ongoing crisis in Ukraine seems to be business as usual with 2 Russian and 1 NASA astronaut.
3. Very few observations of the Regulus Occultation by 163 Erigone from March 19-20.  It would appear that almost the entire observation path was clouded out.  A real disappointment to the IOTA team members not to mention those of us planning to witness this once in a lifetime “disappearance’ of one of the brightest stars in the night sky.

Major Topics Discussed:

1. New gully on Mars (but probably not from water):
http://www.universetoday.com/110483/new-gully-appears-on-mars-but-its-likely-not-due-to-water/#more-110483
Images from NASA’s Mars Reconnaissance Orbiter show a new channel in the southern hemisphere region of Terra Siernum that appeared between November 2010 and May 2013.
The pair of images that shows material at the base of a gully broke out of an older route and eroded a new channel.
This particular feature is likely not due to water.
“Before-and-after HiRISE pairs of similar activity at other sites demonstrate that this type of activity generally occurs in winter, at temperatures so cold that carbon dioxide, rather than water, is likely to play the key role,” the agency said.
Last week, the agency also announced that MRO recovered from an unplanned computer swap that put the spacecraft into safe mode. Incidents of this nature have happened four times before, the agency noted.

2. 360-degree Milky Way panorama from Spitzer:
http://www.universetoday.com/110525/360-degrees-of-milky-way-at-your-fingertips/#more-110525
More than 2 million infrared photos taken by NASA’s Spitzer Space Telescope were jigsawed into a 20-gigapixel click-and-zoom mosaic.
Named GLIMPSE360 (Galactic Legacy Mid-Plane Survey Extraordinaire project), the deep infrared survey captures only about 3% of the sky, but because it focuses on the plane of the Milky Way, where stars are most highly concentrated, it shows more than half of all the galaxy’s 300 billion suns.
In this mosaic you can see jets from young stars, bubbles blown around massive stars, and emission nebulae lit up by the light from stars.
Unlike visual light, infrared light is not stopped by dust, and thus is used by astronomers to view structures in the plane of our galaxy that are obscured in the optical.
http://www.spitzer.caltech.edu/glimpse360/

 

Thanks for listening!
-YorkUniverse Team
_________
YorkUniverse is a co-production of Astronomy.FM and the York University Astronomical Observatory. For more information on us, check out the following links:
webpage: www.yorkuniverse.com
twitter: @YorkUniverse
AFM page: astronomy.fm/yorkuniverse
Observatory webpage: www.yorkobservatory.com
Observatory twitter: @YorkObservatory

Cosmos YES, Congress NO

Show notes for Episode 188, April 10th 2014
Hosts: Paul, Rob C, Hugh, Julie(background)
Title: Cosmos YES, Congress NO

Tonight’s show is full of people!  Starting with the birthday shout-out to Yuri Gagarin (first man in space)  we progress quickly to all the amazing women who have contributed so significantly to modern astronomy (celebrating International Women’s Day).  On the downside, we lament the cuts in the NASA budget and the impact that a world crisis can have on astronomy and space science.  On the upside, we revel in the reboot of Cosmos, commenting upon the opening episode this past week.

This week in space/astronomy history:
1. March 7th, 1962 – Launch of OSO 1 (Orbiting Solar Observatory), first astronomy satellite; main mission was to study the Sun but also to look at celestial sources of UV light, X-rays and gamma-radiation (Suggested by Jen) NASA, wiki
2. March 10th, 1977 – The rings of Uranus were discovered (Suggested by Jen) – although William Herschel apparently observed them in 1789, it is debated whether or not he could have seen them because they are so faint wiki
3. March 10th, 1814 – Spectral Analysis – first observed by Joseph von Fraunhofer (Suggested by Jen) DW, wiki
4. March 9 1934 birthday for Yuri Gagarin, the first man in space, April 12, 1961.

News:
1. International Women’s Day: March 8th, 2014. Shout-out to astronomers past and present:  Jocelyn Bell Burnell (b. 1943), Annie Jump Cannon (1863-1941), Sandra Faber (b. 1944), Caroline Herschel (1750-1848), Helen Sawyer Hogg (1905-1993), Henrietta Swan Leavitt (1868-1921), Cecila Payne-Gaposchkin (1900-1979), Vera Rubin (b. 1929), Carolyn Shoemaker (b. 1929), and Jill Tarter (b. 1944).
2. Asteroids whizzed by Earth.  At distance of roughly 350 000 kilometers, placing its passage inside the orbit of the Moon (385 000 km), th 25-30 metre-wide asteroid DX110 passed the Earth on March 5th, 2014.  DX110 is bigger than the Chelyabinsk meteor (20 metres) but smaller than Tunguska (60 metres). Two other asteroids, 2014 EC and 2014 EF,  also passed even closer, but were slightly smaller at about 10 metres in diameter.  These flybys are not rare, but NASA’s JPL Near-Earth Object Program is constantly watching for these objects. (Suggested Reading: 2014 DX110 Wiki, Bad Astronomy article, NASA)
3. New NASA budget request to the White House. The 2015 NASA Budget proposal has about a 1% cut compared to the 2014 budget; but when your total budget is billions of dollars, as NASA’s is, a 1% cut is 100millions of dollars (in context, the total national budget is trillions of dollars – so NASA’s total budget is less than 0.5% of that).  Areas that may receive more money: space technology (e.g., asteroid capture), commercial spaceflight (e.g., buying launches from SpaceX), heliophysics, new Europa mission (see below).  Areas that may receive cuts: earth science, astrophysics, planetary science, and education.
MER Opportunity and LRO are not on the actual request for funding, they’re on the “wish list” so they’ll probably be gone, CASSINI, CURIOSITY (obviously) and most of the other planetary missions will stay. NASA has committed to a new discovery mission starting in FY15, not sure what it will be these are the “small” 450 million dollar missions like DAWN, GRAIL and Kepler (my favourite!) Pu-238 production will continue to be funded! Yay! This is important for missions to the outer regions of the solar system, so it’s great to see that NASA is going to keep making this. They will be funding 133 million for an asteroid redirect mission, of which details are fairly limited, but 20 million will go to observing near earth objects. SOFIA got mothballed. This is bad! Education funding down by ¼, which is also bad. (Suggested Reading: NASA Fiscal Year Request Summary, Bad Astronomy article,)
Better breakdown from planetary society
Details on SOFIA
4. Ukraine-Crimea influencing astronomy? The impact of the Ukraine-Crimea conflict and a possible “sanctions showdown” with the US could imperil the ISS and indeed other NASA/DoD ;launches.  Soyuz remains the only way for people to reach the ISS and the Atlas 5 main engine is supplied by Russia.  Thus, could US space efforts be a casualty of the current eastern European crisis?
5. Europa Clipper.  One of the missions earmarked for funds in the above budget is the probe to Jupiter’s icy moon, Europa.  The launch date could be as early as the 2020s, and would see the Clipper flyby the moon many times with distance from the surface from 25 km to several thousand kilometres.  Two instruments of particular interest: an infrared spectrometer to study the icy surface, and radar to penetrate the surface ice.  It would also potentially flyby Ganymede and Callisto along the way.  Total estimated cost is about $2 billion.  Europa Clipper follows in the footsteps of Saturn’s Cassini-Huygen’s mission – although there is no mention of a lander for the Clipper.(Suggested Reading: NASA)
6. Mars rock mission. NASA Ames internal study concludes that the SpaceX Dragon capsule would have the capability to perform a sample return mission from Mars. The mission would launch from Earth in 2022, a modified Dragon capsule dubbed the Red Dragon (How cool is that?) would perform a soft landing on the martian surface, collect a sample (possibly a drilled sample!), load it up into a Mars Ascent Vehicle which would ascend out of Mars and come straight back to Earth, landing in a High Earth Orbit where it would be picked up by a second Dragon capsule and delivered safely back to Earth. NASA estimates that the Red Dragon could land up to two metric tonnes of useful payload on Mars (i.e. the equivalent of two Curiosity rovers). (Suggested reading: Space.com article)
In more SpaceX news, next week they’re launching again this time with landing legs. Still landing in the ocean but it’s all progress on the road to reusable rockets.
(Suggested reading: UniverseToday article)
7. Yutu lives! (Sort of)  The YUTU Rover (Jade Rabbit) survived its encounter with the dreaded lunar night and was able to move its instruments around even if the rover itself didn’t move. As we suspected it was an issue with the rover being able to position its solar panels correctly. At night the rover hunkers down around its warm radioactive core to keep sensitive equipment and electronics safe from the harsh environment of the lunar night, however with the disabled mechanical equipment they aren’t able to fold down the sensitive pieces of equipment on the rover’s mast. All this aside, the rover was able to wake up 48 hours behind schedule and while it’s not currently moving it is still able to take panoramic and infrared images and the ground penetrating radar is still functioning normally. They should be just coming out of their third lunar night in the next few days, hopefully everything is still in good shape!
(Suggested reading: UniverseToday article)
8. Using bonded molecules to determine exoplanet atmospheric pressure. Never ceases to amaze me what we can learn just from looking at stuff! They measure the broadening of the 1.06um absorption line corresponding to vibrating and rotating O2-O2 dimers, basically two O2s that are covalently bonded together. The theory goes that as the atmospheric pressure increases you get significantly greater broadening effects from these O2-O2 dimers than you would from a simple O2 monomer. By comparing the relative levels of the two you can determine the effect of atmospheric pressure on the O2, and thereby determine what the atmospheric pressure of the planet is likely to be.
(Suggested reading: UniverseToday article, ArXiV article)
9. Neil deGrasse Tyson’s Cosmos premiered this past week.  A fitting tribute to Carl Sagan’s original series and wonderfully update images and graphics, Cosmos delivered!  Apart from an overcrowded steroid Belt graphic (and an over populated Oort Cloud) there was little to be disappointed in.  For those of us who saw the original series, this promises to be both a ride down memory lane as well as a wonderful modern tribute to teh state of modern astronomy.

Thanks for listening!
-YorkUniverse Team
__________
YorkUniverse is a co-production of Astronomy.FM and the York University Astronomical Observatory. For more information on us, check out the following links:
webpage: www.yorkuniverse.com
twitter: @YorkUniverse
AFM page: astronomy.fm/yorkuniverse
Observatory webpage: www.yorkobservatory.com
Observatory twitter: @YorkObservatory