Messages about Mercury

Courtesy of MESSENGER! (groan)

Sorry, I couldn't resist. Read about it here.

Messages from MESSENGER

NASA's MESSENGER spacecraft recently completed its third flyby of Mercury and the initial science results are available here, here, and here. Imagine what it will accomplish when it is actually in orbit around Mercury!

July 13th Radio Show: The Sun

Slowly working through to backlog of radio shows I need to put online, now available here is the July 13th episode. This program begins my current discussion of recent scientific results concerning the Solar System and, since it lies at its center, I appropriately start with the Sun. And because it is so close to the Sun, I cover Mercury as well. As always, please email me or leave below any questions, comments, or concerns you might have. Thank you for listening!

Description of November 5th Radio Show: Evolution of High-Mass Stars

Already available here, below is a description of the November 5th episode of this radio show, which was devoted to the evolution of high mass stars - stars born with a mass more than eight times that of the Sun. On this program I talked about:

• News: Phoenix Mars Lander hopes to extend lifespan by shutting off some instruments (link), experienced a low power fault brought on by a dust storm; MESSENGER spacecraft images more parts of Mercury never seen before (link); NASA tests prototype lunar rover in Arizona (link); congrats to University of Bremen team for winning ESA rover challenge; first hardware for test flight of NASA's new Ares I-X rocket arrives in Florida; NASA to launch space shuttle Endeavor to International Space Station on November 14th; Hubble Space Telescope servicing mission delayed to give more time to prepare data handling unit to replace the one that failed last month - Hubble now using backup and is thankfully working just fine (link); GALEX - a UV satellite - images galaxy near bright star; GREAT08 PASCAL challenge issued to scientists to figure out how to use weak gravitational lensing to study dark matter (link, by the way - they are already lots of people working on it anyway); new James Bond movie "Quantum of Solace" features scenes filmed at astronomer's guest house at ESO's Paranal Observatory; congrats to Roger Cabana who is now director of NASA's Kennedy Space Center; NASA and South Korea sign statement of intent for future cooperation; congrats to receipient of NASA's Small Business Innovations Research Projects (link); NASA awards contract to support mission controls at Goddard Space Flight Center; ESA adapts technology used for Integral satellite to detect radioactive material in airports; American astronauts vote from space on November 4th (link).
• Wednesday Morning Astronomer (my take on the Astronomy content of this ESPN column): "Ripples in space and time" is not just fluff added to a press release, but does mean something and is a consequence of Einstein's Theory of General Relativity. And even the most diehard string theorists will says that it is a theory that needs to be proven experimentally. They just argue that it is currently the best theory out there.
• Calendar of upcoming Astronomy/science events in the greater Poughkeepsie area
• Evolution of High-Mass Stars: High-mass stars are able to fuse much heavier elements in their core than their lower mass brethern (all the way up to Iron, rather than just Carbon and Oxygen), but as they do so blow off their outer envelopes in powerful winds. The stars with most powerful winds are called Wolf-Rayet stars, and these are believed to be some of the most massive stars in the galaxy, with more than 100 times the mass of the Sun. A binary of such stars was just discovered in the center of the Westerlund 2 star cluster (link). The outer layers of massive stars can be so dense and hot they undergo explosive fusion. Such an event might have powered an outburst observed in 1843 for very nearby massive star eta Carinae - a more powerful outburst than had ever been observed from a star before (link). The outer layers of massive stars aren't stable, and they contract and expands - getting hotter (and looking bluer) when smaller and cooler (and looking red) when larger. They spend most of their time at the extremes, which is why the discovery of a yellow supergiant binary so exciting (link). Integral satellite discovers massive stars orbiting a neutron star or a black hole behind lots of dusts.

Hope you enjoyed and, as always, any and all feedback is greatly appreciated and wanted. Thank you for listening!

Description of October 15th Radio Show: Star Formation, Planet Formation, and Massive Stars

Long available here, below is the detailed description of this radio show:

• News: Evidence that boundaries of sunspots play an important role in the producing the Solar wind (link); NASA's spacecraft MESSENGER completes second flyby of Mercury, images a substantial portion of Mercury's surface never observed before (link); ESA spacecraft Venus Express observes the Earth to use as a template for studying extrasolar planets; Mars Odyssey shifting orbit around Mars to better measure the spectrum of interesting regions of the Martian surface; Phoenix Mars Lander obtains new samples for study (link); asteroid collides with Earth exactly when and where as predicted; Spitzer spacecraft releases images of Comet Holmes obtained after its eruption last year, show large dust grains ejected during this event; Cassini flew by Saturn's moon Enceladus again last week to better study the plumes emanating from its surface (link), recent flyby of Saturn's moon Titan - the largest moon in the Solar system - by Cassini reveals that Titan's atmosphere can hold onto Saturn's magnetic field as it passes through (link), and Cassini images a massive cyclone at Saturn's North Pole similar to the one long seen at Saturn's South Pole (link); IBEX spacecraft to study particle accelerated at the outer boundary of the Solar System ready for launch (link); ESA has delived all of its instruments to the Indian Lunar satellite Chandrayaan-1; new crew departed for International Space Station; congrats to Dr. Ellen Ochoa, deputy director of NASA's Johnson Space Center, for being the first female recipient of the "Engineer of the Year" award given at the Hispanic Engineer National Achievement Awards Conference; research at Queen's University in UK developing a robotic system to repair satellites in space (link); ESA to test Intermediate Experiment Vehicle in 2012; NASA examines heat shield from Apollo mission to help design new lunar crew vehicle (link); NASA studying possibility of putting a large liquid mirror on the Moon; NASA issues 2008 edition of Spinoff magazine, available here.
• Wednesday Morning Astronomer (an Astronomer's response to this ESPN column): I agree that commercial rocket launches are a long, way, away from being a viable alternative. However, the lack of sunspots seen recently from the Sun isn't really a problem, and the reversal of Earth's magnetic field is going to take 100s if not 1000s of year, not occur during 2012.
• Calendar of upcoming events in the greater New York / Poughkeepsie area.
• Molecular Clouds and the Formation of Stars and Planets: Observation of a molecular cloud by astronomers in the Canary Islands discovers naphthalene, a precursor to amino acids (link); Spitzer observations of star forming region W5 show evidence for star formation being triggered by stars which just formed in the area (link); a similar process believed to be occurring in the star forming region NGC 346 located in the Small Magellanic Cloud (link); this is evidence that the Solar System was the result of a shock wave collided with its progenitor gas cloud (link); infrared survey of the Milky Way done using Spitzer space telescope detects stars in all phases of their creation - from the proto-stars created by the collapse of their natal molecular clouds to young stars blowing holes in the interstellar medium after they "turn on" (link; evidence for stars forming in the gas stripped from a galaxy as it collides with another galaxy (link); ESO's Very Large Telescope uses optical interferometry to study the structure of the disk formed by the collapse of a dense cloud of gas into a star(link); evidence for water being formed and destroyed in the outflows of material from this disk as it collapses onto the central star; chemical compositions of comets suggests that material flowed from the inner part of this disk to the outer part as our Sun formed (link 1, link 2); isotopic abundance of Oxygen in early Solar system changed during the formation of the Sun (link); asteroids in the Solar System believed to contain carbon molecules which can survive entry into the Earth's atmosphere and possibly be building blocks for life on the Earth (link); gap observed in the gas and dust disk around a young star believed to be evidence for a planet forming there (link); future telescopes believed might be able to detect disk gaps formed by planets as small as Mars (link); astronomers at University of Toronto might have made an actual picture of a planet orbiting another star (link); bizzare new exoplanet found - not sure if it is a planet or a brown dwarf (link); evidence for recent collision between two planets seen around distant star BD+20 307 (link); most massive star in Milky Way weiged in at over 110 times that of the Sun (link).

Hope you enjoyed this program and, as always, any and all feedback is appreciated. Again, thank you very much for listening.

Description of October 8th Radio Show: Solar System

Already available here, below is a description of the October 8th episode of this radio show:

• News: NASA's Phoenix Mars Lander discovers snow falling in Mars's upper atmosphere, and evidence for liquid past in the soil (link; Eberswalde Crater chosen as preliminary site for NASA's next rover to Mars called Mars Science Laboratory; Mars Science Laboratory to have a computer chip to measure the wind on Mars (link); MESSENGER spacecraft flies by Mercury for a second time on October 6th (link); NASA developing sensor to allow lunar landers to automatically determine a safe landing site for future return to the Moon (link); ESA's SMART-1 mission makes 3D map on Moon's south pole (link); Hubble Space Telescope (HST) enters "safe" mode due to error in device which transmits science data to Earth, resulting in postponement of final servicing mission; 10th anniversary of Hubble Heritage Project, which distributes the prettiest pictures taken by HST; ESA's GOCE satellite has new launch date of 2008 October 27; NASA's IBEX spacecraft ready for launch on October 19; ESA's Planck satellite - the next satellite to study the Cosmic Microwave Background (listen to inteviews with Dr. Gary Hinshaw and Dr. Dan Babich for more infomation on the Cosmic Microwave Background) - almost done with final pre-launch testing; teams behind the three different proposals for NASA/DoE Joint Dark Energy Mission (JDEM) told to work together on a single, joint, design; European astroparticle physics list the seven major experiments they want to build (link); ESO's Very Large Telescope in Chile takes highest-resolution image of Jupiter ever done from the ground; privately developed Falcon 1 rocket finally has successful launch; congratulations to Custer Institute and Observatory for receiving a Break-Thru Mini-Grant for their research and public outreach activities (for more information on their activities, listen to my interview with Dr. Jeffrey Owen Katz); congratulations to Robert Cabana for succeeding William Parsons as head of NASA's Kennedy Space Center; congratulations to teams awarded five-year grants by the NASA Astrobiology Institute (link); NASA issues new challenge for college students to design tools for next generation of Moon rovers (website); new art exhibit at Pasadena, CA's Art Center College of Design inspired by pictures taken by Spitzer Space Telescope.
• Wednesday Morning Astronomer (an Astronomer's response to the astronomy content in this ESPN column): I don't think SCP 06F6, which had 100 day long outburst of optical light, is the result of intergalactic warfare. Sorry.
• Calendar of upcoming Astronomy / Science events in the greater New York City / Poughkeepsie area.
• Solar System: So far during 2008, the Sun has produced many fewer sunspots than any other year in the last 50 years - not that surprising though; NASA's RHESSI satellite finds that Sun not a perfect sphere with the equator wider than the distance between the poles (link); changes in Sun's output of light has very SLIGHT effect on Earth's temperature (link); ESA's Venus Express mission, in orbit around Venus, has made 3D map of Venus's winds over Southern hemisphere (link); observations done by ESA's Mars Express satellites determines why Mars's Southern Polar Cap misplaced in the Martian summer- result of local weather systems; difference between Mars's Northern and Southern hemisphere (e.g. thickness of crust, number of craters) believed to be the result of ancient collision with a meteorite that essentially melted the entire northern hemisphere of Mars (link 1, link 2); astronomers at Armagh Observatory see meteorites striking Mars's surface (link); ancient Moon believed to have been rich in water; same is true for ancient Mars - though it might have lasted only a short period of time (link); might have once rained on Mars as well (link); NASA spacecrafts photograph evidence for avalanches on Mars (link); glaciers on Mars show evidence for recent climate activity (link); Mars has undergone five periods of high amounts of volcanic activity (link); atmospheres of Mars and Venus interact with the Solar wind in a similar fashion (link); graphite found in Solar System meteorites, if graphite exists in interstellar medium, could complicate using supernovae to measure the distance to galaxies - the best evidence for the existence of dark energy (link); meteorites could be the source of all the Platinum and Iridium found on Earth (link); Jupiter and Saturn may have liquid metal helium in their cores (link); Cassini spacecraft makes a 3D image of the region responsible for the low-frequency radio emission emitted by Saturn (link); Saturn's moon Titan keeps some of Saturn's magnetic field when it leaves Saturn's magnetosphere; new Pluto-like object found in outer Solar System (link); "backward-orbiting" comet discovered (link); Taiwanese-American Occultation Survey discovers no objects between 2 miles - 17 miles big inthe Kuiper Belt - suggests they either broke apart in collisions or stuck together to form bigger objects.

Hope you enjoy, and thank you very much for listening!

July 30th Radio Show online: Mercury, Saturn, and the Outer Solar System

The July 30th radio show is now online and available here. This show marked the end of our trip through the Solar System, and I discussed the latest news concerning the innermost planet in the Solar System (Mercury), as well as one of the outer ones (Saturn), and recent measurements concerning the edge of the Solar System. In detail I covered:

• News: Thank you to Home Depot for donating a new and much-needed roof to the Custer Institute and Observatory; Phoenix Mars Lander producing 3D image of surrounding area (link,3D map); NASA starts funding a GPS program for the Moon (link); NASA invites media for a demo of Lunar Surface Manipulator concept on August 1st; NASA to hold media briefing for final Hubble servicing mission September 8-9; NASA and USDA sign an agreement for the USDA to conduct research on the International Space Station; NASA develops a new webpage to show the latest satellite imagery of fires on the Earth; NASA's Kennedy Spaceflight Center hosts a program for Florida high school students to work on challenges related to returning to the Moon; 2008 General Aviation Technology Challenge to be held August 4-10 in Santa Rosa, CA; NASA's 50th Anniversary honored at EAA AirVenture 2008 air show in Oshkosh, WI July 28 - Aug 3; NASA successfully tests a parachute designed to slow down the descent of the first-stage motor from the Ares I rocket, the successor to the space shuttle; congratulations to NASA's programmers on the Data-Parallel Line Relaxation and Adaptive Modified Gerchberg-Saxton Phase Retrieval programs for winning NASA's 2007 Software of the Year award; ongoing dispute between NSF and local residents concerning the Advanced Technology Solar Telescope to be located on top of Mauna Kea; editorial in July 23rd New York Times calling for development of solar power stations in space (link); positive movie review of WALL-E in July 24th edition of Nature magazine (I concur whole-heartedly); new exhibit at Museum of History of Science in Oxford, UK on Ferdinand Verbiest - court astronomer in China in the late 1600s; Perseid Meteor shower to peak on August 12th, expected to be a good one.
• Calendar of upcoming Astronomy events in the greater Poughkeepsie / New York City area
• Mercury: The closest planet to the Sun, it is one of the least studied planets in the Solar System because it is difficult to get space craft there (it takes a lot of fuel to decelerate a space craft launched from the Earth to get so close to the Sun. A space craft launched from the Earth will stay in the Earth's orbit if it doesn't fire rockets.) However, NASA recently launched a space craft called MESSENGER to study Mercury, and while it isn't in orbit around this planet just yet, on January 14th, 2008 it did it's first flyby during which it made some measurements that revealed some exciting new information about this planet that were summarized in the July 4th, 2008 edition of Science magazine. It discovered that the smooth surface in the Caloris Region basin is likely the result of volcanic activity on Mercury - long after such volcanism was expected to end; Mercury's magnetic field is generated by an active dynamo in the core, and not the remnant of a magnetic field formed earlier that was locked into its crust as previously thought; the cooling of Mercury's core shrunk so much that is caused huge wrinkles in the crust; and made the first observations of charged particles around Mercury kicked off the surface by the Solar Wind and sunlight (link 1, link 2, link 3).
• Saturn: In my opinion, one of the most beautiful planets in the Solar System with its extensive ring system and plentiful moons, Saturn and its surroundings have been studied extensively over the passed 4 years by the recently-extended Cassini spacecraft. Recent results include a temporal and altitude temperature variation in Saturn's atmosphere over its equator likely the equivalent of seasonal variations seen on Earth; a vortex over the south pole of Saturn; a secondary aurora on Saturn resulting from charged particles produced by volcanism on its moon (link); extremely powerful lightning on Saturn the source of observed bursts of radio emission seen from this planet (link); Saturn's innermost A-ring absorbs material ejected by geysers on Enceladus; the different velocity between the dust and gas ejected by the geysers on Enceladus (dust slower, gas faster) due to dust bouncing off the walls of the fractures in the surface of Enceladus from which they are produced (link); Cassini flyby through the material ejected from Enceladus detects organic compounds (link) - leading to suggestions that their might be life on this moon (link); common black coating found on the surface of many of Saturn's icy moons; variability and fine structure in Saturn's F-ring caused by moonlets in this ring (link); discovery of partial ring system around Saturn's moon Rhea (article); Saturn's moon Titan believed to more liquid hydrocarbons on its surface than present in the Earth (link) and has a rapidly changing rotation period likely the result of an internal water ocean.
• Pluto: It might not be classified as a planet any longer, but it is still an interesting object to study. NASA launched a space craft a few years ago called New Horizons to study it in detail, and it appears that Pluto's atmosphere will still be around when it arrives.
• Edge of the Solar System: The sun resides in the Milky Way, and one edge of the Solar System is defined where the solar wind - the stream of highly energetic particles produced in the Sun's corona - is decelerated by the surrounding interstellar medium. This region is called a "termination shock", since the wind is suddenly terminated there, about both Voyager spacecraft have crossed this boundary, Voyager 2 most recently on August, 31 2007. Voyager 2 crossed this shock at a distance very different than Voyager 1, suggesting that the termination shock is dented - possibly a result of the Milky Way's magnetic field. It was also able to make measurements of the density structure, composition, and magnetic field in this region - discovering that a lot of the energy in the solar wind is transferred to interstellar material ionized by solar wind particles (link). The STEREO spacecraft has also recently discovered high energy neutral particles from this region (link).

Thanks a lot for listening, hope you enjoyed, and any and all feedback is extremely appreciated.

April 30th Radio Show - Mercury and Venus

The April 30th radio show is now online, available here. Our tour of the Solar System continues with the two innermost planets, Mercury and Venus. I made a mistake on-air when I discussed why it is so hard to get a spacecraft from Earth to Mercury, and have added an errata to the mp3 available above, so even if you heard this show live I strongly encourage you to listen to the mp3 so you can hear the correct information. On this program, I also covered:

• News: Solar flare on Sun observed to trigger a "tsunami"-like shock wave through Sun's atmosphere as well as launch a coronal mass ejection on April 26; congratulation to Dr. Adam Riess (JHU/STScI) for being elected to the American Academy of Arts and Sciences, to the Galaxy Evolution Explorer (GALEX) team for successfully maintaining this UV telescope in space for 5 years; happy birthday to the Hubble Space Telescope, which celebrated 18 years from launch on April 27th - to celebrate, pretty pictures of 59 colliding galaxies were made public (link); assembly of the Herschel telescope, an European space-based infrared telescope, has been completed; DAMA/LIBRA experiment in Italy has claimed to directly detect "dark matter" on Earth again, other groups skeptical; shoulder motor on Mars rover Opportunity experiencing technical difficulties (link); Austria declares intention to join European Organization for Astronomical Research in the Southern Hemisphere (ESO); astronauts interviewed live by students on April 30 (link); NASA's Jet Propulsion Laboratory (JPL) to have an open house May 3-4
• Wednesday Morning Astronomer, a response to the astronomy content in Gregg Easterbrook's column "Tuesday Morning Quarterback" (available here) - yes, Gamma Ray Bursts (GRBs) are absolutely amazing but, no, I don't think a flurry of them were timed to mark the death of Arthur C. Clarke. I know it was a joke, but...
• Calendar of upcoming events in the greater Poughkeepsie/New York City area
• Mercury: Small rocky planets very close to the Sun, very poorly understood relative to many of the other planets in the Solar System since it is hard to observe and hard to send spacecraft to. NASA's recently launched a spacecraft to Mercury called MESSENGER, which has already flown by Mercury once. During this flyby, it imaged several craters which have dark rims, a crater with a shiny bottom, a crater wit radial spokes coming out of its center, and a very weak magnetic field emanating from its surface. The origins of these features are not known, and hopefully with more data obtained by MESSENGER after it enters Mercury's orbit in the March 2011 people will be able to figure it out. Also, scalloped-edge cliffs (called "lobate scarps") on Mercury's surface possible result of very thin mantle underneath Mercury's crust (link)
• Venus: Has, by far, the thickest atmosphere of any of the Rocky Planets in the Solar System. Recent results include the discovery of a variable bright haze layer, likely composed of sulfuric acid, at the top of its atmosphere whose origin is unknown; possible evidence for active volcanos on Venus's surface detected by the European Space Agency's Venus Explorer (link); Carbon Monoxide plays a more important role in atmosphere of Venus and Mars than previously thought (link); eye of a hurricane observed at the south pole of Venus observed to flicker and change shape within a matter of days (link); it is possible that Venus was created from the collision between two very large objects in early Solar System, could explain why - despite similar mass and distance from the Sun - Earth and Venus or so different (link); another possibility for these difference is lake of plate tectonics on Venus (link).

Hope you enjoyed, and thank you very much for listening. As always, please leave below or email any questions, comments, or concerns you might have.

Mercury visible

Since Mercury is so close to the Sun, it is often hidden in the Sun's glare and therefore very difficult to see from the Earth. However, this Tuesday evening, (May 6th), just after sunset the crescent Moon glides by Mercury in the darkening western sky. A sky map and photos are available at http://spaceweather.com, which was the sources of much of this information.