31 August 2018
The two science orbiters of the joint ESA-JAXA BepiColombo mission are connected in their launch configuration and the European science orbiter and transport module have been given the go-ahead to be loaded with propellants.
The mission completed its Qualification Acceptance Review in the last week, which confirms it is on track for its 19 October launch. The three-spacecraft mission is currently scheduled to launch on an Ariane 5 at 03:45 CEST (01:45 GMT) on 19 October, or 22:45 local time in Kourou on 18 October, with the launch window remaining open until 29 November.
Following the successful fuelling readiness review on 30 August, the chemical propellants – such as hydrazine – can be added to the European Mercury Transfer Module (MTM) and Mercury Planetary Orbiter (MPO).
“These important reviews represent further key milestone in our launch campaign, bringing us to the final stages of our launch preparations, while in the longer term enabling the journey and operations at Mercury,” says Ulrich Reininghaus, ESA’s BepiColombo project manager.
“With the fueling activities planned for 5–12 September, a technical point of no return will be reached. After mechanical stacking, final electrical health check and transfer to the final assembly building, the launch will be the next major event.”
BepiColombo stack 'fit check'
The transfer module will use both ion propulsion and chemical propulsion, in combination with gravity assist flybys at Earth, Venus and Mercury to bring the two science orbiters close enough to Mercury to be gravitationally captured into its orbit.
There, MPO will use its small thrusters to deliver JAXA’s Mercury Magnetospheric Orbiter (MMO) into its elliptical orbit around Mercury, before separating and descending to its own orbit closer to the planet.
This month the two science modules were arranged in their launch configuration for the first time in over a year; the last occasion was at ESA’s technical centre in the Netherlands during final testing before shipment to Europe’s Spaceport in Kourou, French Guiana.
The MTM will be integrated at the bottom of the stack once the propellant-loading activities have been completed. A test-run of the integration was already exercised last week with the unfueled modules. The sunshield that will protect the MMO from the Sun’s radiation on the seven year journey will also be added much closer to launch.
“The long journey to Mercury has not yet started, but I feel the two science orbiters already have a strong bond between them, thanks to the long history of this mission,” says Go Murakami, JAXA’s BepiColombo project scientist. “I believe they will achieve a very successful mission with their joint science measurements.”
BepiColombo orbits
MMO’s main science goals are to provide a detailed study of the magnetic environment of Mercury, the interaction of the solar wind with the planet, and the diverse chemical species present in the exosphere – the planet’s extremely tenuous ‘atmosphere’.
The MPO will focus more on surface processes and composition, and together with MMO, will help piece together the full picture of the interaction of the solar wind on the planet’s environment and surface. Together they will watch how this interaction at the surface feeds back into what is observed in the exosphere and how that varies both in time and location – something that can only be achieved with two spacecraft in such complementary orbits.
“Seeing the two BepiColombo science orbiters finally attached together and knowing that they will now stay in this configuration for the next seven years is quite emotional,” says Johannes Benkhoff, ESA’s BepiColombo project scientist. “It’s another strong indication that we will start our mission soon and I’m really looking forward to all the science measurements we have planned with instruments on these two orbiters.”
Bepi Colombo timeline
For more images of the launch preparations at Kourou visit the BepiColombo image gallery.
For further information, please contact:
Markus Bauer
ESA Science Communication Officer
Tel: +31 71 565 6799
Mob: +31 61 594 3 954
Email:
markus.bauer@esa.intET,
News | August 30, 2018
Martian Skies Clearing over Opportunity Rover...
A planet-encircling dust storm on Mars, which was first detected May 30 and halted operations for the Opportunity rover, continues to abate.
With clearing skies over Opportunity's resting spot in Mars' Perseverance Valley, engineers at NASA's Jet Propulsion Laboratory in Pasadena, California, believe the nearly 15-year-old, solar-powered rover will soon receive enough sunlight to automatically initiate recovery procedures -- if the rover is able to do so. To prepare, the Opportunity mission team has developed a two-step plan to provide the highest probability of successfully communicating with the rover and bringing it back online.
"The Sun is breaking through the haze over Perseverance Valley, and soon there will be enough sunlight present that Opportunity should be able to recharge its batteries," said John Callas, Opportunity project manager at JPL. "When the tau level [a measure of the amount of particulate matter in the Martian sky] dips below 1.5, we will begin a period of actively attempting to communicate with the rover by sending it commands via the antennas of NASA's Deep Space Network. Assuming that we hear back from Opportunity, we will begin the process of discerning its status and bringing it back online."
The rover's last communication with Earth was received June 10, and Opportunity's current health is unknown. Opportunity engineers are relying on the expertise of Mars scientists analyzing data from the Mars Color Imager (MARCI) aboard NASA's Mars Reconnaissance Orbiter (MRO) to estimate the tau near the rover's position.
"The dust haze produced by the Martian global dust storm of 2018 is one of the most extensive on record, but all indications are it is finally coming to a close," said MRO Project Scientist Rich Zurek at JPL. "MARCI images of the Opportunity site have shown no active dust storms for some time within 3,000 kilometers [about 1,900 miles] of the rover site."
With skies clearing, mission managers are hopeful the rover will attempt to call home, but they are also prepared for an extended period of silence. "If we do not hear back after 45 days, the team will be forced to conclude that the Sun-blocking dust and the Martian cold have conspired to cause some type of fault from which the rover will more than likely not recover," said Callas. "At that point our active phase of reaching out to Opportunity will be at an end. However, in the unlikely chance that there is a large amount of dust sitting on the solar arrays that is blocking the Sun's energy, we will continue passive listening efforts for several months."
The additional several months for passive listening are an allowance for the possibility that a Red Planet dust devil could come along and literally dust off Opportunity's solar arrays. Such "cleaning events" were first discovered by Mars rover teams in 2004 when, on several occasions, battery power levels aboard both Spirit and Opportunity increased by several percent during a single Martian night, when the logical expectation was that they would continue to decrease. These cleaning dust devils have even been imaged by both rovers on the surface and spacecraft in orbit (see
https://mars.nasa.gov/resources/5307/the-serpent-dust-devil-of-mars/).The chances are small that dust accumulation would be the root cause of Opportunity's lack of communication. Nonetheless, each day during the passive phase, JPL's Radio Science group will scour the signal records taken by a very sensitive broadband receiver of radio frequencies emanating from Mars, looking for a sign that the rover is trying to reach out.
Even if the team hears back from Opportunity during either phase, there is no assurance the rover will be operational. The impact of this latest storm on Opportunity's systems is unknown but could have resulted in reduced energy production, diminished battery performance, or other unforeseen damage that could make it difficult for the rover to fully return online.
While the situation in Perseverance Valley is critical, the rover team is cautiously optimistic, knowing that Opportunity has overcome significant challenges during its 14-plus years on Mars. The rover lost use of its front steering -- its left-front in June of 2017, and right front in 2005. Its 256-megabyte flash memory is no longer functioning. The team also knows that everything about the rover is well beyond its warranty period -- both Opportunity and its twin rover, Spirit, were constructed for 90-day missions (Spirit lasted 20 times longer and Opportunity is going on 60 times). The rovers were designed to travel about 1,000 yards, and Opportunity has logged more than 28 miles. Through thick and thin, the team has seen their rover soldier on. Now, Opportunity engineers and scientists of Opportunity are planning, and hoping, that this latest dilemma is just another bump in their Martian road.
"In a situation like this you hope for the best but plan for all eventualities," said Callas. "We are pulling for our tenacious rover to pull her feet from the fire one more time. And if she does, we will be there to hear her."
Updates on the dust storm and tau can be foundhere.
JPL, a division of Caltech in Pasadena, built Opportunity and manages the mission for NASA's Science Mission Directorate, Washington.
For more information about Opportunity, visit:
https://www.nasa.gov/rovershttps://marsrovers.jpl.nasa.govNews Media Contact
DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.govJoAnna Wendel
NASA Headquarters, Washington
202-358-1003
Joanna.r.wendel@nasa.gov2018-206
LES ÂMES TRISTES, L'ORAGE DU TEMPS ET L'HORIZON.
A planet-encircling dust storm on Mars, which was first detected May 30.
https://www.jpl.nasa.gov/news/news.php?feature=7227&utm_source=iContact&utm_medium=email&utm_campaign=nasajpl&utm_content=opportunity20180830-1 …
BepiColombo science orbiters stacked together.
http://www.esa.int/Our_Activities/Space_Science/BepiColombo/BepiColombo_science_orbiters_stacked_together …
GOOD JOB, Y'BECCA.
TAY
WITH,
ALMA Observatory
@almaobs
29 août
#BreakingNews! 📡ALMA observed an unstoppable monster in the early #Universe. Astronomers obtained the most detailed anatomy chart of a monster galaxy located 12.4 billion light-years away. 🌀
http://www.almaobservatory.org/en/press-releaAstronomers obtained the most detailed anatomy chart of a monster galaxy located 12.4 billion light-years away. Using the Atacama Large Millimeter/submillimeter Array (ALMA), the team revealed that the molecular clouds in the galaxy are highly unstable, which leads to runaway star formation. Monster galaxies are thought to be the ancestors of the huge elliptical galaxies in today’s Universe; therefore, these findings pave the way to understand the formation and evolution of such galaxies.
“One of the best parts of ALMA observations is to see the far-away galaxies with unprecedented resolution,” says Ken-ichi Tadaki, a postdoctoral researcher at the Japan Society for the Promotion of Science and the National Astronomical Observatory of Japan, lead author of the research paper published in the journal Nature.
Monster galaxies, or starburst galaxies, form stars at a startling pace; 1000 times higher than the star formation rate in our Galaxy. However, why are they so active? To tackle this problem, researchers need to know the environment around the stellar nurseries. Drawing detailed maps of molecular clouds is one crucial step to scout these cosmic monsters.
Tadaki and the team targeted a chimerical galaxy COSMOS-AzTEC-1. This galaxy was first discovered with the James Clerk Maxwell Telescope in Hawai`i, and later the Large Millimeter Telescope (LMT) in Mexico found an enormous amount of carbon monoxide gas in the galaxy and revealed its hidden starburst. The LMT observations also measured the distance to the galaxy, and found that it is 12.4 billion light-years [1].
Researchers have found that COSMOS-AzTEC-1 is rich with the ingredients of stars, but it was still difficult to figure out the nature of the cosmic gas in the galaxy. The team utilized the high resolution and high sensitivity of ALMA to observe this monster galaxy and obtain a detailed map of the distribution and the motion of the gas. Thanks to the most extended ALMA antenna configuration of 16 km, this is it the highest resolution molecular gas map of a distant monster galaxy.
“We found that there are two distinct large clouds several thousand light years away from the center,” explains Tadaki. “In most distant starburst galaxies, stars are actively formed in the center. So, it is surprising to find off-center clouds.”
Artist’s impression of the monster galaxy COSMOS-AzTEC-1. This galaxy is located 12.4 billion light-years away and is forming stars 1000 times more rapidly than our Milky Way Galaxy. ALMA observations revealed dense gas concentrations in the disk and intense stars formation in those concentrations. Credit: National Astronomical Observatory of Japan.
Artist’s impression of the monster galaxy COSMOS-AzTEC-1. This galaxy is located 12.4 billion light-years away and is forming stars 1000 times more rapidly than our Milky Way Galaxy. ALMA observations revealed dense gas concentrations in the disk and intense stars formation in those concentrations. Credit: National Astronomical Observatory of Japan.
The astronomers further investigated the nature of the gas in COSMOS-AzTEC-1 and found that the clouds throughout the galaxy are very unstable, which is unusual. In a typical situation, the inward gravity and outward pressure are balanced in the clouds. Once gravity overcomes pressure, the gas cloud collapses and forms stars at a rapid pace. Then, stars and supernova explosions at the end of the stellar life cycle blast out gases, which increases the outward pressure. As a result, gravity and pressure reach a balanced state and star formation continues at a moderate pace. In this way star formation in galaxies is self-regulating. However, in COSMOS-AzTEC-1, the pressure is far weaker than the gravity and hard to balance. Therefore, this galaxy shows runaway star formation and morphed into an unstoppable monster galaxy.
The team estimated that the gas in COSMOS-AzTEC-1 will be completely consumed in 100 million years, which is ten times faster than in other star-forming galaxies.
However, why is the gas in COSMOS-AzTEC-1 so unstable? Researchers do not have a definitive answer yet, but galaxy merger is a possible cause. Galaxy collision may have efficiently transported the gas into a small area and ignited intense star formation.
“At this moment, we have no evidence of merger in this galaxy. By observing other similar galaxies with ALMA, we want to unveil the relation between galaxy mergers and monster galaxies,” summarizes Tadaki.
Notes
[1] The measured redshift of COSMOS-AzTEC-1 is z=4.3. A calculation based on the latest cosmological parameters measured with Planck (H0=67.3 km/s/Mpc, Ωm=0.315, Λ=0.685: Planck 2013 Results) yields the distance of 12.4 billion light-years. Please refer to “Expressing the distance to remote objects” for the details.
Additional Information
These observation results appear as Tadaki et al. “The gravitationally unstable gas disk of a starburst galaxy 12 billion years ago” in Natureon August 30, 2018.
The research team members are:
Ken-ichi Tadaki (Japan Society for the Promotion of Science / National Astronomical Observatory of Japan), Daisuke Iono (National Astronomical Observatory of Japan / SOKENDAI), Min S. Yun (University of Massachusetts), Itziar Aretxaga (Instituto Nacional de Astrofísica, Óptica y Electrónica), Bunyo Hatsukade (The University of Tokyo), David H. Hughes (Instituto Nacional de Astrofísica, Óptica y Electrónica), So Ikarashi (University of Groningen), Takuma Izumi (National Astronomical Observatory of Japan), Ryohei Kawabe (National Astronomical Observatory of Japan), Kotaro Kohno (The University of Tokyo), Munju Lee (Nagoya University), Yuichi Matsuda (National Astronomical Observatory of Japan / SOKENDAI), Kohichiro Nakanishi (National Astronomical Observatory of Japan / SOKENDAI), Toshiki Saito (Max Planck Institute for Astronomy), Yoichi Tamura (Nagoya University), Junko Ueda (National Astronomical Observatory of Japan), Hideki Umehata (RIKEN), Grant W. Wilson (University of Massachusetts), Tomonari Michiyama (SOKENDAI), Misaki Ando (SOKENDAI), Patrick Kamieneski (University of Massachusetts).
This research was supported by JSPS KAKENHI (Grant Number 17J04449).
The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).
ALMA construction and operations are led by ESO on behalf of its Member States; by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America; and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.
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