What's up in the solar system, June 2016 edition: Juno approaches Jupiter
The main excitement this month is the impending orbit insertion of Juno, which is coming up on July 4; the press room at the Jet Propulsion Laboratory opens on June 30. It's also a great month to look up at bright planets in the night sky -- Mars just passed opposition and Saturn will be at opposition on June 3 so are up all night long, while Jupiter is still hanging around in the west in the evening sky. Other than that, it's routine science operations for Akatsuki, Lunar Reconnaissance Orbiter, Chang'e 3, possibly Chang'e 5 T1, ARTEMIS, Odyssey, Opportunity, Mars Express, Mars Reconnaissance Orbiter, Curiosity, Mars Orbiter Mission, MAVEN, Dawn, Rosetta, Cassini, New Horizons, and the Voyagers, while Hayabusa2, ExoMars Trace Gas Orbiter, and Juno are cruising toward their destinations. Three astronauts will return to Earth from the space station on June 18. Last month I promised the first public release of data from the Pluto encounter phase of the New Horizons mission, but it hasn't happened yet; keep your fingers crossed that it will happen this month.
Here's Olaf Frohn's chart of active space missions.
What's Up in the Solar System diagram by Olaf Frohn (updated for April 2017)
A diagram, updated once a month, of active space missions traveling beyond Earth orbit. Contains links to past diagrams.
Earth Launches and Landings (contributed by Jason Davis)
Expedition 47 comes to a close June 18, when Tim Kopra (NASA), Tim Peake (ESA) and Yuri Malenchenko (Roscosmos) climb aboard their Soyuz TMA-19M spacecraft and depart from the International Space Station. That will leave the orbital lab's crew complement at three until Kate Rubins (NASA), Takuya Onishi (JAXA) and Anatoli Ivanishin (Roscosmos) launch from Baikonur aboard Soyuz MS-01 on June 24. This will be the first flight of an upgraded Soyuz MS series spacecraft; two uncrewed Progress MS vehicles have already flown to the station. In other June ISS logistics news, Cygnus OA-6 will likely be unberthed this month and sent into the atmosphere for destructive reentry. It has remained attached to the station since March to allow astronauts to stuff it with extra trash.
An Ariane 5 launches a pair of communications satellites on June 8. In addition to Soyuz MS-01, two Russian launches are scheduled this month, according to RussianSpaceWeb.com. Earth science satellite GEO-IK-2 No. 2 heads to orbit June 4, and the communications satellite Intelsat DLA-2 launches atop a Proton on June 8. Finally, Spaceflight Now reports India is scheduled to launch an Earth observation satellite June 10, while China may debut its new Long March 7 rocket on June 26.
Color image of Venus' glowing atmosphere from Akatsuki's 2-micron camera
Akatsuki captured this photo on March 25, 2016. It is composed of images taken at two infrared wavelengths, 1.735μm (red channel) and 2.26μm (blue channel), which are sensitive to two different sizes of particles in Venus' clouds. A green channel was synthesized from a combination of the two. The orange glow around the terminator results from Venus' long twilight in its thick atmosphere.
Mars' northern autumnal equinox is coming up (on July 4), so the days are getting longer and warmer at the southern hemisphere landing sites of the two Mars rovers. Mars just passed through opposition (on May 22), so Earth-Mars distance is at a minimum.
Mars Odyssey's 15th Mars arrival anniversary is coming up on October 24; I don't have any news on mission status, which is generally a good thing. My favorite recent images from the THEMIS website are this one showing a beautiful, fresh Stenheim crater; this one of the lovely, sinuous Buvinda Vallis; and this one of textbook streamlined mid-channel islands in Shalbatana Vallis.
I don't have much news on the Mars Orbiter Mission. The ISRO annual report (PDF) mentioned that the Mars Colour Camera "has acquired more than 440 images so far." It doesn't specify the date when that number was valid, though based on text in the rest of the document I think it is as of February 2016. There is no news on any plans to share the image data with the public. The annual report mentions that "local, national, and even international media continued to provide conspicuous coverage" of Mars Orbiter Mission -- it sounds like ISRO is finding public interest in Mars exploration to be greater than in Earth exploration. Hopefully that will encourage ISRO to increase deep-space exploration activities...and to share image data!
MAVEN's next two deep-dip campaigns are planned for early June and late July of this year. Last month, a data visualization team from Goddard Spaceflight Center won two prizes from the American Association for Advancement of Science, the publishers of Science magazine, for their work to use MAVEN data to explain Martian atmospheric loss.
Throughout May, Opportunity has continued science in Marathon Valley. The Microscopic Imager issue that I discussed last month has been resolved. For most of the month, from sols 4345-4374, Opportunity was at one location, Pierre Pinaut, which allowed the rover the time to capture a nice color panoramic view of the surroundings. The rover continues to generate more than 600 watts of power from its solar panels, but as is expected for this time of year the atmospheric opacity is inching upward, now at 0.6.
NASA / JPL / Cornell / ASU / James Sorenson
View from the head of Marathon Valley, Opportunity sols 4348-4375
Opportunity methodically took the Pancam images for this panorama over a period of a few weeks (April 17-May 15, 2016), while working at a site called "Perre Pinaut."
I rather like this version of the image with a simulated Opportunity dropped into it.
Sean Dorán from NASA / JPL / Cornell / ASU / James Sorenson image and NASA / JPL / Christian A. Lopez rover model
View from the head of Marathon Valley with simulated Opportunity
A simulated view of the Opportunity rover in the position it occupied on sol 4334 has been dropped into a panorama taken by Opportunity on sols 4348-4875.
On the other side of Mars, Curiosity has finally descended the western side of the Naukluft plateau. The rover's current position is probably pretty close to the westernmost limit of its traverse. Now it will head south, keeping isolated dunes on the left side and the Murray buttes on the right side as it crosses the Bagnold dune field at a place where there are large gaps between the dunes. According to Ryan Anderson, there should be a new HiRISE image of Curiosity shortly.
Rosetta had a bit of a scare last weekend. It went into safe mode while only 5 kilometers from the comet. Contact was lost for almost 24 hours. A command in the blind recovered the spacecraft and all is fine now; they are bringing the science instruments back online. These safe modes happen when Rosetta's star trackers confuse comet dust for stars, an event that is more likely when the spacecraft is closer to the comet. What does that mean for the plans for bringing Rosetta very close to the comet near the end of the mission? The ESA report says that the star trackers will actually be taken "out of the loop" during the final descent, and possibly even during the final weeks of the mission. They also mention that the spacecraft will probably brought down "close to Philae's original planned landing site at Agilkia, most likely on 30 September." Meanwhile, Rosetta continues to yield new science results. The latest is a report of the first direct detection of a simple amino acid, glycine, in the comet's coma. As always, check here for the latest NavCam image releases and here for the OSIRIS image of the day.
Dawn recently completed its 1000th orbit of Ceres and continues in its low-altitude mapping orbit, 385 kilometers above the surface. This month, June 2016, will be the final month of Dawn's prime mission, but the spacecraft is expected to continue to operate in an extended mission for as long as its maneuvering fuel lasts. Marc Rayman reports that Dawn completed a six-week-long stereo mapping campaign May 25, and has now begun another one, looking in a different direction; the multiple views of terrain from different angles will allow the calculation of detailed digital elevation models of the asteroid. The infrared channel of its visible and infrared mapping spectrometer is losing the ability to cool itself -- an unsurprising symptom of age in an instrument that has operated far more than originally planned -- but other than that, the instruments are all operating well. Check the Photojournal for the latest images!
Juno is now just 34 days and about 22 million kilometers from Jupiter orbit insertion. As of May 27, it is feeling Jupiter's gravitational pull more strongly than that of the Sun. It's going to begin performing approach imaging with Junocam on June 12; I will be posting a very detailed article about JunoCam imaging plans next week. Beginning in November, you'll be able to vote on targets for future Junocam imaging. But already, you can visit the JunoCam website to discuss features visible in amateur astronomers' Jupiter images, and the JunoCam team really wants you to participate!
Cassini has just passed through periapsis of Rev 236, headed for its 121st flyby of Titan on June 7. Jason Perry's Looking Ahead article for Rev 236 provides details on Cassini's plans. One June 3, it will take photos of a nearly-full Dione from a distance of 950,000 kilometers, and then observe Rhea from somewhat closer. But icy moon observations aren't the point of its current inclined orbit. On June 6, Cassini will take advantage of the orbit inclination to perform a radio occultation of Saturn's main ring system. The Titan flyby will be at an altitude of 975 kilometers and will tip the orbit to an even higher angle, from 35.3 to 42.4 degrees. During its closest approach, Cassini will collect a radar swath across Titan's high southern latitudes -- the last radar swath Cassini will ever get of such southern terrain. On June 11, Cassini will gather color photos of the main ring system and Saturn "as a sort of parting shot for Cassini," Jason writes. Sniff. There are 469 days remaining in the mission. Rev 237 begins on June 17. As seen from here on Earth, Saturn will be at opposition on June 3, and since we're only a year away from northern summer solstice, the rings are wide open to view from Earth. Check the raw images page for the latest views from Cassini's cameras.
The biggest news from New Horizons this month is probably the release of a new set of U.S. postage stamps bearing images of the spacecraft and of Pluto. They also got some photos of another Kuiper belt object, 1994 JR1, discovering (among other things) that the little body has a very fast rotation rate, spinning once in 5.4 hours. Last month's LORRI data downlink has concentrated on the early departure phase, including lots of photos like this one of the diminishing "O" of Pluto's backlit atmosphere. Visit my LORRI data summary page and look for the yellow-highlighted images on the Encounter and DP1 pages to see all the new stuff. I am still waiting to see the first formal release of data from New Horizons to the Planetary Data System; I've been told that they delivered the data in April, but for whatever reason, the Planetary Data System has not released the data yet. First data releases are usually a little late due to various hiccups, but I'm going to be pretty irritated if the first Pluto data release is delayed beyond the first anniversary of the flyby on July 14. New Horizons blog entries last month included one by Henry Throop on being the behind-the-scenes photographer during the flyby, one by Jorge Nuñez on systems engineering the LORRI camera, and one by Veronica Bray on science with crater measurements. Check their science images gallery for the latest interpretation of New Horizons images!
Finally, the Voyagers are still going, going, going. Voyager 1 is at 135.1 AU from the Sun, and Voyager 2 is at 111.3 AU.