Category Archives: Astrophysics & Space Exploration

Ossiris-REx begins preliminary survey phase ahead of orbital insertion

NASA’s OSIRIS-REx spacecraft after a 2 billion km journey, has reached and is now in orbit around asteroid Bennu.   See previous post.

Below is a series of images taken by OSIRIS-REx at a distance of about 80 km (50 mi.) The images constitute one full revolution of the asteroid.

The spacecraft is now in the Preliminary Survey Phase which began on December 3, 2018, and marks the first time that the OSIRIS-REx spacecraft will operate around the asteroid. The spacecraft will make a total of five passes over the north pole, equator, and south pole at a range of 4.3 miles (7 km). The primary science goals of Preliminary Survey are to estimate Bennu’s mass, refine the asteroid’s spin state model, and generate a global shape model at a resolution of 75-cm.  With this information orbital insertion can be planned and detailed (and close) survey of the asteroid can begin.

SPP-Preliminary-Survey-Poster-12-19-17

Our Star’s sibling – looks like a good candidate

Its 4.5 billion years since our solar system formed in a  gaseous nebula.  These nebula formed from the explosive collapse of stars, larger than Sol, when they have exhausted much of their hydrogen.  These Supernova cast much of their mass into space forming  a gaseous nebula.  These nebula are however large –  much larger than our solar system and are incubators of star formation, sometimes hundreds of stars, much like the glowing nebula in the image below.

NASA, ESA, and the Hubble SM4 ERO Team – http://www.hubblesite.org/newscenter/archive/releases/2009/25/image/e/
Composed of gas and dust, the pictured pillar resides in a tempestuous stellar nursery called the Carina Nebula, located 7500 light-years away in the southern constellation of Carina. Taken in visible light, the image shows the tip of the three-light-year-long pillar, bathed in the glow of light from hot, massive stars off the top of the image. Scorching radiation and fast winds (streams of charged particles) from these stars are sculpting the pillar and causing new stars to form within it. Streamers of gas and dust can be seen flowing off the top of the structure. Hubble’s Wide Field Camera 3 observed the Carina Nebula on 24-30 July 2009. The composite image was made from filters that isolate emission from iron, magnesium, oxygen, hydrogen and sulphur.

Overtime, the varied gravitational environment in the galaxy results in stars formed from the same nebula drifting apart, however they will retain the same composition and have similar spectral characteristics and maybe even be of comparable in size.  Finding these siblings would require a massive star survey.  We would have to know the distance from Earth, the relative speed and direction and the composition.  Given that there are a vast number of stars in our immediate neighborhood –  this is a daunting task.

The Gaia spacecraft is performing just such a  survey of the Milky Way.  Gaia is measuring the distance, velocity and spectral characteristics for a billion stars in our galaxy has now spotted what appears to be a twin (HD186302) of Sol and it has near identical spectral characteristics.  Of the 200,000 stars in the spectral Gaia catalog only one star, HD186302, has near-identical chemistry to Sol.

HD186302 is a G3-Type main sequence star with about same surface temperature as Sol and is about the same age, 4.5 BY.  HD186302 is located 184 light years from Earth,   which sounds like it’s very distant.  However, to achieve this separation if Sol and HB186302 were original 1-2 light-years apart within the nebula it would only require a relative velocity between Sol and HD186302 of 65,000 km/hr since formation to have achieved the current separation.  In galactic terms this is a very realistic relative speed.

 

Osiris meets NEO asteroid bennu on Monday – live stream

After the excitement of the Insight landing on Mars earlier in the week  – there is more space adventure in store next week.  OSIRIS-REx arrives at near-Earth asteroid 101955 Bennu, on Monday.

NASA’s Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) will make contact with Bennu at 1200 EST or 1700 Zulu.

The first image was obtained using one of the three cameras on-board the spacecraft (PolyCam) from a distance of 330 kilometers. Multiple exposures allow for estimation of rotation speed. The scientific team used a super-resolution algorithm to combine eight images and produce a higher resolution view of the asteroid. Although Bennu occupies barely 100 pixels in the detector, it is possible to identify some features on its surface, like large boulders.

There will be a live stream of the event at Nasa Live.

On Dec. 3, OSIRIS-REx will begin operations around the asteroid, passing over its north pole, south pole and equator at an altitude of only 6 km. This will allow the spacecraft to determine its mass, how fast it’s spinning and generate a model of the asteroid prior to retrieving a surface sample and returing it to planet Earth in 2023.

The journey for the asteroid-chasing OSIRIS-REx began back in September 2016 and three years later it’s finally close enough to tag the space rock. The spacecraft is equipped with five instruments and will survey the asteroid for a year, before selecting a site to retrieve a sample. OSIRIS-REx won’t touch down on the asteroid, like Japan’s Hayabusa 2 did earlier this year, instead opting to drop a lower pressure blower on an retractable arm (TAGSAM) onto the surface to suck up a sample for Earth return.

Instruments

The OSIRIS-REx Laser Altimeter (OLA) will provide a 3-D map of asteroid Bennu’s shape, which will allow scientists to understand the context of the asteroid’s geography and the sample location. OLA is provided by the Canadian Space Agency in exchange for Canadian ownership of a portion of the returned asteroid sample. NASA’s OSIRIS-REx spacecraft will travel to the near-Earth asteroid Bennu and bring at least a 60-gram (2.1-ounce) sample back to Earth for study.

The OSIRIS-REx Thermal Emission Spectrometer (OTES) will conduct surveys to map mineral and chemical abundances and to take the asteroid Bennu’s temperature. OTES is the first such instrument built entirely on the Arizona State University (ASU), Tempe campus.

The OSIRIS-REx Visible and Infrared Spectrometer (OVIRS) will measure visible and near infrared light from the asteroid Bennu. The instrument’s observations could be used to identify water and organic materials.

The Regolith X-Ray Imaging Spectrometer (REXIS) instrument designed to image X-ray emission from Bennu in order to provide an elemental abundance map of the asteroid’s surface.

The TAGSAM arm will be responsible for collecting a sample from Bennu’s surface.

 

 

Totally Awesome – A massive game changer

On December 1st, Spaceflight will launch its SSO-A satellite ride share on a Falcon 9 B1046 booster from Vandenberg on the west coast of the USA.  SSO-A integrates 63 satellites into a  single stack –  in a single launch.  

The ability to deploy this many satellites into low earth orbit makes launching small satellites increasing economic.  With costs as low as $295,000 for a 5kg cube-sat –  its simply changes the game.  The pricing ranges from a high of $59k/kg for the smallest form-factor cube-sat of 34cm x 10cm x 10cm to $28k/kg for a 1000 kg 350cm x 200cm satellite.

The multi-satellite payload includes 49 CubeSats and 15 larger micro-satellites. They will be launched into sun-synchronous low-earth orbits.

The satellites belong to 34 government and commercial organizations from 17 countries — including the United States, Australia, India, Thailand, South Korea, Canada, Jordan, Kazakhstan, and nine European states (Italy, Netherlands, Finland, Spain, Switzerland, UK, Germany, Poland, and Brazil).

Before the Big Bang & Conformal Cyclic Cosmology

What was there before the Big Bang?  This is one of the most perplexing contemplations in physics and astronomy.  There are number of theories to glimpse this distant past, however data is likely very scant, but maybe them is evidence of a prior universe in clear sight.

Here is a series of quite remarkable videos to help you contemplate what went before, before the oldest observable photons, 13.5 GA.

While I strongly recommend that you simply watch these videos in series, the last in the series is likely the most remarkable and my opening comments alluded to this.

Conformal Cyclic Cosmology(CCC) is a scheme whereby the universe is seen to be cyclic even though it never recollapse and bounces back out. Instead it undergoes whats called a conformal rescaling. What’s that ? Watch the film, all will be explained. CCC promises to solve many deep mysteries in cosmology such as why was the entropy of the big bang so low? What happened before the big bang? Where does the dark matter in our universe come from? This film addresses both the theory of CCC and the possibility of experimental verification.

Below you will recognise the image of the Cosmic Background Radiation gathered from the COBE Satellite over a  9 year period.

NINE YEAR MICROWAVE SKY http://map.gsfc.nasa.gov/media/121238/index.html Nine Year Microwave Sky The detailed, all-sky picture of the infant universe created from nine years of WMAP data. The image reveals 13.77 billion year old temperature fluctuations (shown as color differences) that correspond to the seeds that grew to become the galaxies. The signal from our galaxy was subtracted using the multi-frequency data. This image shows a temperature range of ± 200 microKelvin. Credit: NASA / WMAP Science Team WMAP # 121238 Image Caption 9 year WMAP image of background cosmic radiation (2012)

While much was made of the homogeneity of the data and the implications of this there are obvious patters in the data and various researchers have found concentric low variance circles in the CMB as can be seen in the image below.

Concentric low variance circles in the CMB data, Adam DeAbreua et al, Journal of Cosmology and Astroparticle Physics

Penrose and Meisner suggest that Conformal Cyclic Cosmology implies that these structures are the product of the collision of supermassive black holes which occurred towards the end (or indeed the infinity) of an earlier universe.  This is a most remarkable suggestion.  In a future universe a similar pattern may be all that is residual from our universe. Conformal Rescaling of gravity at the scale of the singularity could reconcile gravity and quantum mechanics.

Enjoy, I most certainly have.

Jupiter Has Two Magnetic South Poles

Jupiter as seen from the Juno spacecraft.
NASA/JPL-Caltech/SwRI/MSSS/Gabriel Fiset

A complex dynamo inferred from the hemispheric dichotomy of Jupiter’s magnetic field

The Juno spacecraft, which is in a polar orbit around Jupiter, is providing direct measurements of the planet’s magnetic field close to its surface. A recent analysis of observations of Jupiter’s magnetic field from eight (of the first nine) Juno orbits has provided a spherical-harmonic reference model (JRM09) of Jupiter’s magnetic field outside the planet.

The non-dipolar nature of the magnetic field in the northern hemisphere and the dipolar nature in the southern hemisphere is apparent. The equatorial view is centred near the Great Blue Spot and shows the linkage of magnetic field lines that enter through the Great Blue Spot. The contoured surface on which the field lines shown start and end is at r = 0.85RJ, where the density of field lines is proportional to the radial magnetic field strength and is depicted by the colour scale (red outward flux, blue inward flux).

This model is of particular interest for understanding processes in Jupiter’s magnetosphere, but to study the field within the planet and thus the dynamo mechanism that is responsible for generating Jupiter’s main magnetic field, alternative models are preferred.

The authors report maps of the magnetic field at a range of depths within Jupiter. They find that Jupiter’s magnetic field is different from all other known planetary magnetic fields. Within Jupiter, most of the flux emerges from the dynamo region in a narrow band in the northern hemisphere, some of which returns through an intense, isolated flux patch near the equator. Elsewhere, the field is much weaker. The non-dipolar part of the field is confined almost entirely to the northern hemisphere, so there the field is strongly non-dipolar and in the southern hemisphere it is predominantly dipolar. The authors that Jupiter’s dynamo, unlike Earth’s, does not operate in a thick, homogeneous shell, and we propose that this unexpected field morphology arises from radial variations, possibly including layering, in density or electrical conductivity, or both.

Original Research

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Truely Breathtaking

Saturn’s moon Dione hangs in front of Saturn’s rings in this view taken by NASA’s Cassini spacecraft during the inbound leg of its last close flyby of the icy moon. North on Dione is up. The image was acquired in visible light with the Cassini spacecraft narrow-angle camera on 17 August 2015. The view was acquired at a distance of approximately 98,000 miles (158,000 kilometres) from Dione and at a sun-Dione-spacecraft, or phase, angle of 35 degrees. Image scale is 3,100 feet (950 metres) per pixel. Image credit: NASA/JPL-Caltech/Space Science Institute.

This spectacular image of Dione and Saturn’s rings is simply fantastic.  Dione is a small moon with a diameter of 1,120 km, surface gravity of 0.232 m/S2 and semi-major axis similar to that of Earth’s moon.  Its orbital period is only 2.7 days however, 10% of our moon, reflecting the Saturn’s greater mass (95 times that of Earth).

49 Years Ago – Today

Neil Armstrong on the Moon, July 1969: NASA/JPLOn this day 49 years ago , Apollo 11 landed the first two people on the Moon, mission commander Neil Armstrong and pilot Buzz Aldrin.  Our first step into the cosmos?  There are 14,000 stars within 100 light years of Earth, where will we be in 10,000 years?

To put this event into perspective some of the historic documents merit review and provide some understanding of the challenges and the technology of the time.

Reports from the Research Steering Committee on Manned Spaceflight, Space Sciences board etc for the period 1959 through 1971.  From the NASA Historical archives

The Apollo 11 Press Kit, released Sunday July 6, 1969

“The United States will launch a three-man spacecraft toward the Moon on July 16 with the goal of landing two astronaut-explorers on the lunar surface 4 days later.

If the mission –called Apollo 11–is successful, man will accomplish his long-term dream of walking on another celestial body.”

Apollo 11 Mission Report, Manned spaceflight Center, Houston Texas, November 1969

“The purpose of the Apollo 11 mission was to land men on the lunar surface and to return them safely to earth. The crew were Neil A. Arm¬strong, Commander; Michael Collins, Command Module Pilot; and Edwin E. Aldrin, Jr., Lunar Module Pilot.

The space vehicle was launched from Kennedy Space Center, Florida, at 8:32:00 a.m., e.s.t., July 16, 1969. The activities during earth orbit checkout, translunar injection, transposition and docking, spacecraft ejection, and translunar coast were similar to those of Apollo 10. Only one midcourse correction, performed at about 27 hours elapsed time, was required during trans lunar coast.

Neil Armstrong walks on the Moon. July 20, 1969. Image AS11-40-5873 courtesy NASA/JSC

The spacecraft was inserted into lunar orbit at about 76 hours, and the circularization maneuver was performed two revolutions later. Initial checkout of lunar module systems was satisfactory, and after a planned rest period, the Commander and Lunar Module Pilot entered the lunar module to prepare for descent.

The two spacecraft were undocked at about 100 hours, followed by separation of the command and service modules from the lunar module. Descent orbit insertion was performed at approximately 101-l/2 hours, and powered descent to the lunar surface began about 1 hour later. Operation of the guidance and descent propulsion systems was nominal. The lunar module was maneuvered manually approximately 1100 feet downrange from the nominal landing point during the final 2-1/2 minutes of descent. The spacecraft landed in the Sea of Tranquillity at 102:45:40. The landing coordinates were 0 degrees 41 minutes 15 seconds north latitude and 23 degrees 26 minutes east longitude referenced to lunar map ORB-II-6(100), first edition, December 1967. During the first 2 hours on the surface, the two crewmen performed a postlanding checkout of all lunar module systems. Afterwards, they ate their first meal on the moon and elected to perform the surface operations earlier than planned.

Crater 308: This photo was taken by the Apollo 11 astronauts as they circled the far side of the Moon, which is rough with craters and marks. Image AS11-44-6611 courtesy NASA/JSC.

Considerable time was deliberately devoted to checkout and donning of the back-mounted portable life support and oxygen purge systems. The Commander egressed through the forward hatch and deployed an equipment module in the descent stage. A camera in this module provided live television coverage of the Commander descending the ladder to the surface, with first contact made at 109:24:15 (9:56:15 p.m. e.s.t., July 20, 1969). The Lunar Module Pilot egressed soon thereafter, and both crewmen used the initial period on the surface to become acclimated to the reduced gravity and unfamiliar surface conditions. A contingency sample was taken from the surface, and the television camera was deployed so that most of the lunar module was included in its view field. The crew activated the scientific experiments, which included a solar wind detector, a passive seismometer, and a laser retro-reflector. The Lunar Module Pilot evaluated his ability to operate and move about, and was able to translate rapidly and with confidence. Forty-seven pounds of lunar surface material were collected to be returned for analysis. The surface exploration was concluded in the allotted time of 2-l/2 hours, and the crew reentered the lunar module at lll-l/2 hours.

Ascent preparation was conducted efficiently, and the ascent stage lifted off the surface at 124-l/4 hours. A nominal firing of the ascent engine placed the vehicle into a 45- by 9-mile orbit. After a rendezvous sequence similar to that of Apollo 10, the two spacecraft were docked at 128 hours. Following transfer of the crew, the ascent stage was jettisoned, and the command and service modules were prepared for trans earth injection.

The return flight started with a 150-second firing of the service propulsion engine during the 31st lunar revolution at 135-l/2 hours. As in trans lunar flight, only one midcourse correction was required, and passive thermal control was exercised for most of trans earth coast. Inclement weather necessitated moving the landing point 215 miles downrange. The entry phase was normal, and the command module landed in the Pacific Ocean at 19 5-l/4 hours. The landing coordinates, as determined from the onboard computer, were 13 degrees 19 minutes north latitude and 169 de-grees 09 minutes west longitude.

After landing, the crew donned biological isolation garments. They were then retrieved by helicopter and taken to the primary recovery ship, USS Hornet. The crew and lunar material samples were placed in the Mobile Quarantine Facility for transport to the Lunar Receiving Laboratory in Houston. The command module was taken aboard the Hornet about 3 hours after landing.

With the completion of Apollo 11, the national objective of landing men on the moon and returning them safely to earth before the end of the decade had been accomplished.”

First detection of complex organics on an extraterrestrial water-world

200 AMU macromolecular organics detected in plumes on Enceladus

Cassini was intentionally crashed into the atmosphere of Saturn late in 2016, to avoid contamination of any of the moons of the planet.  While that ended data collection from Saturn and its moons, data analysis continues to produce surprises.  Saturn’s moon Enceladus harbours a global ocean beneath an icy crust and above a  rocky core.

Icey crust of Enceladus showing evidence of recent active “tectonism” and an absence of impact structures over large portions of the moon.  Source NASA/JPL

A surprising discovery in 2005 which initiated widespread debate on the potential of Enceladus to harbour life was the observation of active cryo-volcanic plumes ejecting ice and vapour into space.   It was conjectured that hydrothermal activity in the core of the moon was powered by tidal dissipation produced by the strong gravitational field of Saturn.  Studies of the plume in a close fly-by by Cassini revealed the present of simple organic molecules mostly below 50 Atomic Mass Units (AMUs).  In a new study just published in Nature, Frank Postberg et al report the observation of emitted ice grains containing organic material with molecular mass above 200 AMU, complex macromolecular organic matter.

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Plumes From Saturn’s Moon Enceladus Hint That It Could Support Life. Source: CreditNASA/JPL-Caltech, via Space Science Institute

Two mass spectrometers onboard Cassini, the Cosmic Dust Analyser and the Ion and Neutral Mass Spectrometer performed compositional in-situ measurements of material emerging from the surface of Enceladus, both within the plume and Saturn’s E-ring.  the E-ring has been formed by ice grains escaping the moon’s gravity.

The organic fragments, of up to 200 units of molecular mass, are created as the ice grains hit the dust-analysing instrument on Cassini at speeds of about 30 000 kilometres per hour, but the researchers believe that, prior to the collision, the grains contain the original, even larger molecules, which could have molecular weights of thousands of atomic mass units.

Scientists calculate molecular mass, or weight, as the sum of weights of individual atoms contained in the molecule. Previously, Cassini had only detected lightweight organic molecules at Enceladus that were much smaller than the most recently found fragments.

Such large molecules can only be created by complex chemical processes – including those related to life. Alternatively, they could come from primordial material as found in some meteorites or, more likely, be generated by hydrothermal activity.

The authors suggest the presence of a refractory organic rich film at the top of the oceanic water table as the most plausible way to generate the observed grains.  They suggest that this insoluble organic layer would exist at the top of the water layer likely at the base and within the large cracks evident on the surface of the moon.

This discovery is the first ever detection of complex organics on an extraterrestrial body.  In an European space Agency press release, Frank Postberg commented:

“It is the first ever detection of complex organics coming from an extraterrestrial water-world.  We found large molecular fragments that show structures typical for very complex organic molecules. These huge molecules contain a complex network often built from hundreds of atoms of carbon, hydrogen, oxygen and likely nitrogen that form ring-shaped and chain-like substructures.”

“In my opinion the fragments we found are of hydrothermal origin, having been processed inside the hydrothermally active core of Enceladus: in the high pressures and warm temperatures we expect there, it is possible that complex organic molecules can arise,” says Frank.

Be very happy –  it happened in your lifetime.

Macromolecular organic compounds from the depths of Enceladus

Frank Postberg,  Nozair KhawajaBernd AbelGael ChobletChristopher R. GleinMurthy S. GudipatiBryana L. HendersonHsiang-Wen HsuSascha KempfFabian KlennerGeorg Moragas-KlostermeyerBrian MageeLenz NölleMark PerryRené ReviolJürgen SchmidtRalf SramaFerdinand StolzGabriel TobieMario Trieloff & J. Hunter Waite

Abstract

Saturn’s moon Enceladus harbours a global water ocean1, which lies under an ice crust and above a rocky core2. Through warm cracks in the crust3 a cryo-volcanic plume ejects ice grains and vapour into space4,5,6,7 that contain materials originating from the ocean8,9. Hydrothermal activity is suspected to occur deep inside the porous core10,11,12, powered by tidal dissipation13. So far, only simple organic compounds with molecular masses mostly below 50 atomic mass units have been observed in plume material6,14,15. Here we report observations of emitted ice grains containing concentrated and complex macromolecular organic material with molecular masses above 200 atomic mass units. The data constrain the macromolecular structure of organics detected in the ice grains and suggest the presence of a thin organic-rich film on top of the oceanic water table, where organic nucleation cores generated by the bursting of bubbles allow the probing of Enceladus’ organic inventory in enhanced concentrations.

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Solar Activity remains subdued – with the chance of a C-Class Flare. Surface Temp remain at 5778K – largely unchanged for the last 100 Million Years.

Face of the sun 20170324 – Courtesy NASA and the SOHO Mission: https://sohowww.nascom.nasa.gov/sunspots/

“Analysis of Solar Active Regions and Activity from 22/2100Z to 23/2100Z: Solar activity has been at very low levels for the past 24 hours. There are currently 1 numbered sunspot regions on the disk.
IB. Solar Activity Forecast: Solar activity is expected to be very low with a slight chance for a C-class flare on days one, two, and three (24 Mar, 25 Mar, 26 Mar)”

The continues to show little sunspot activity and is very quiet as we enter the solar minimum.

Sun Spot Number Progression during solar cycles 23 and 24 Courtesy NASA: http://www.swpc.noaa.gov/products/solar-cycle-progression

 

Could we now be entering the period prior to the Maunder Minimum cold period

Solar Cycles 3 through 6 compared with Solar Cycles 23 through 24 Courtesy: https://wattsupwiththat.com/2013/03/05/how-long-to-the-2425-solar-minimum/

 

 

 

Solar  cycles 22 and 23 are show very similar trends to SC 03 and 04 which receded a 70 year period when there were no reported sunspots resulting in reduced insolation and a very cold period in northern europe.