Universe Today

August 16, 2017August 17, 2017 by Ken Kremer

Station Crew Grapples SpaceX Dragon Delivering Tons of Science After Thunderous Liftoff: Launch & Landing Gallery

The SpaceX Dragon CRS-12 cargo craft is now attached to the International Space Station after arriving on Aug. 16, 2017. It delivered over 3 tons of science and supplies to the six person Expedition 52 crew. Credit: NASA TV

KENNEDY SPACE CENTER, FL – Following a two day orbital chase and ballet of carefully choreographed thruster firings, the SpaceX Dragon cargo capsule launched at lunchtime on Monday Aug. 14 with tons of science and supplies arrived in the vicinity of the International Space Station (ISS) this morning, Wednesday, Aug 16.

While Dragon maneuvered in ever so slowly guided by lasers, NASA astronaut Jack Fischer and ESA (European Space Agency) astronaut Paolo Nespoli carefully extended the stations robotic arm to reach out and grapple the gumdrop shaped capsule.

They deftly captured the Dragon CRS-12 resupply spacecraft slightly ahead of schedule at 6:52 a.m. EDT with the station’s 57.7-foot-long (17.6 meter-long) Canadian-built robotic arm while working at a robotics work station in the seven windowed domed Cupola module.

The SpaceX Dragon cargo craft is pictured approaching the International Space Station on Wednesday morning Aug. 16, 2017. Credit: NASA

The million pound orbiting outpost was traveling over the Pacific Ocean north of New Zealand at the time of capture.

Liftoff of the SpaceX Falcon 9 took place precisely on time 2 days earlier with ignition of the 9 Merlin 1D first stage engines from seaside pad 39A at NASA’s Kennedy Space Center in Florida today (Aug. 14) at 12:31 p.m. EDT (1631 GMT).

SpaceX launched its 12th resupply mission to the International Space Station from NASA’s Kennedy Space Center in Florida at 12:31 p.m. EDT on Monday, Aug. 14, 2017. Credit: Ken Kremer/Kenkremer.com

The two stage Falcon 9 stands 213-foot-tall (65-meter-tall). The combined output of the 9 Merlin 1D first stage engines generates 1.7 million pounds of liftoff thrust, fueled by liquid oxygen and RP-1 propellants.

See an exciting gallery of launch imagery and videos including the thrilling ground landing of the 156 foot tall first stage booster back at Cape Canaveral at Landing Zone-1 – from this author and several space colleagues.

Monday’s picture perfect lunchtime liftoff of the unmanned SpaceX CRS-12 Dragon cargo freighter bound for the ISS and loaded with over 3 tons of science, research hardware and supplies including a hefty cosmic ray detector named ISS-CREAM, medical research experiments dealing with Parkinson’s disease, lung and heart tissue, vegetable seeds, dozens of mice and much more – came off without a hitch.

Ground controllers then carried out the remainder of the work to berth the SpaceX Dragon cargo spacecraft at the Earth facing port on the Harmony module of the International Space Station at 9:07 a.m. EDT.

This illustration of the International Space Station shows the current configuration with four visiting vehicle spaceships parked at the space station including the SpaceX Dragon CRS-12 cargo craft that arrived Aug. 16, 2017, the Progress 67 resupply ship and two Soyuz crew ships. Credit: NASA

The crew was perhaps especially eager for this Dragons arrival because tucked inside the more than 3 tons of cargo was a stash of delicious ice cream treats.

“The small cups of chocolate, vanilla and birthday cake-flavored ice cream are arriving in freezers that will be reloaded with research samples for return to Earth when the Dragon spacecraft departs the station mid-September,” said NASA.

Indeed the crew did indeed open the hatches today, early than planned, a few hours after arrival and completion of the requisite safety and leak checks.

The SpaceX Dragon cargo craft is pictured approaching the International Space Station on Wednesday morning Aug. 16, 2017. Credit: NASA TV

The whole sequence was broadcast on NASA TV that began live arrival coverage at 5:30 a.m showing numerous stunning video sequences of the rendezvous and grappling often backdropped by our precious Home Planet.

The current multinational Expedition 52 crew serving aboard the ISS comprises of Flight Engineers Paolo Nespoli from ESA, Jack Fischer, Peggy Whitson and Randy Bresnik of NASA and Sergey Ryazanskiy and Commander Fyodor Yurchikhin of Roscosmos.

Launch of SpaceX Falcon on Dragon CRS-12 mission to the ISS from NASA’s Kennedy Space Center in Florida at 12:31 p.m. EDT on Monday, Aug. 14, 2017. Credit: Julian Leek

The Dragon resupply ship dubbed Dragon CRS-12 counts as SpaceX’s twelfth contracted commercial resupply services (CRS) mission to the International Space Station for NASA since 2012.

SpaceX holds a NASA commercial resupply services (CRS) contract that includes up to 20 missions under the original CRS-1 contract.

The 20-foot high, 12-foot-diameter Dragon CRS-12 vessel is carrying more than 6,400 pounds ( 2,900 kg) of science experiments and research instruments, crew supplies, food water, clothing, hardware, gear and spare parts to the million pound orbiting laboratory complex. 20 mice are also onboard. This will support dozens of the 250 research investigations and experiments being conducted by Expedition 52 and 53 crew members.

The Expedition 52 crew poses for a unique portrait. Pictured clockwise from top right are, Flight Engineers Paolo Nespoli, Jack Fischer, Peggy Whitson, Sergey Ryazanskiy, Randy Bresnik and Commander Fyodor Yurchikhin. Credit: NASA/Roscosmos/ESA

Video Caption: CRS-12 launch from Pad 39A on a Falcon 9 rocket. Pad camera views from the launch of the CRS-12 mission carrying 6415 pounds of supplies and equipment to the International Space Station on August 14, 2017. Credit: Jeff Seibert

The SpaceX Falcon 9/Dragon CRS-12 launch was the first of a rapid fire sequence of a triad of launches along the Florida Space Coast over the next 11 days of manmade wonder – Plus a Total Solar ‘Eclipse Across America’ natural wonder sandwiched in between !!

Watch for Ken’s continuing onsite CRS-12, TRDS-M, and ORS 5 and NASA mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

Ground landing of SpaceX Falcon 9 first stage at Landing Zone-1 (LZ-1) after SpaceX launched its 12th resupply mission to the International Space Station from NASA’s Kennedy Space Center in Florida from pad 39A at 12:31 p.m. EDT on Monday, Aug. 14, 2017. Credit: Ken Kremer/Kenkremer.com

………….

Learn more about the upcoming ULA Atlas TDRS-M NASA comsat on Aug. 18, 2017 , SpaceX Dragon CRS-12 resupply launch to ISS on Aug. 14, Solar Eclipse, NASA missions and more at Ken’s upcoming outreach events at Kennedy Space Center Quality Inn, Titusville, FL:

Aug 17-18: “TDRS-M NASA comsat, SpaceX CRS-12 resupply launches to the ISS, Intelsat35e, BulgariaSat 1 and NRO Spysat, SLS, Orion, Commercial crew capsules from Boeing and SpaceX , Heroes and Legends at KSCVC, ULA Atlas/John Glenn Cygnus launch to ISS, SBIRS GEO 3 launch, GOES-R weather satellite launch, OSIRIS-Rex, Juno at Jupiter, InSight Mars lander, SpaceX and Orbital ATK cargo missions to the ISS, ULA Delta 4 Heavy spy satellite, Curiosity and Opportunity explore Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings

Blastoff of SpaceX Dragon CRS12 on its 12th resupply mission to the International Space Station from NASA’s Kennedy Space Center in Florida at 12:31 p.m. EDT on Monday, Aug. 14, 2017 as seen from the VAB roof. Credit: Ken Kremer/Kenkremer.com

August 16, 2017August 17, 2017 by Matt Williams

The Most Distant Massive Galaxy Observed to Date Provides Insight into the Early Universe

A Hubble image of the galaxy cluster Abell 1689, which acts as a lens to focus the light from much more distant galaxies, including some very dusty star-forming galaxies in the early universe (seen as the nearly point-like blue smudges in this image). Credit: NASA-Hubble

In their pursuit of learning how our Universe came to be, scientists have probed very deep into space (and hence, very far back in time). Ultimately, their goal is to determine when the first galaxies in our Universe formed and what effect they had on cosmic evolution. Recent efforts to locate these earliest formations have probed to distances of up to 13 billion light-years from Earth – i.e. about 1 billion years after the Big Bang.

From this, scientist are now able to study how early galaxies affected matter around them – in particular, the reionization of neutral atoms. Unfortunately, most early galaxies are very faint, which makes studying their interiors difficult. But thanks to a recent survey conducted by an international team of astronomers, a more luminous, massive galaxy was spotted that could provide a clear look at how early galaxies led to reionization.

The study which details their findings, titled “ISM Properties of a Massive Dusty Star-forming Galaxy Discovered at z ~ 7“, was recently published in The Astrophysical Journal Letters. Led by researchers from the Max Planck Institute for Radio Astronomy in Bonn, Germany, the team relied on data from the South Pole Telescope (SPT)-SZ survey and ALMA to spot a galaxy that existed 13 billion years ago (just 800 million years after the Big Bang).

*Illustration of the depth by which Hubble imaged galaxies in prior Deep Field initiatives, in units of the Age of the Universe. Credit: NASA and A. Feild (STScI)*

In accordance with Big Bang model of cosmology, reionization refers to the process that took place after the period known as the “Dark Ages”. This occurred between 380,000 and 150 million years after the Big Bang, where most of the photons in the Universe were interacting with electrons and protons. As a result, the radiation of this period is undetectable by our current instruments – hence the name.

Just prior to this period, the “Recombination” occurred, where hydrogen and helium atoms began to form. Initially ionized (with no electrons bound to their nuclei) these molecules gradually captured ions as the Universe cooled, becoming neutral. During the period that followed – i.e. between 150 million to 1 billion years after the Big Bang – the large-scale structure of the Universe began to form.

Intrinsic to this was the process of reionization, where the first stars and quasars formed and their radiation reionized the surrounding Universe. It is therefore clear why astronomers want to probe this era of the Universe. By observing the first stars and galaxies, and what effect they had on the cosmos, astronomers will get a clearer picture of how this early period led to the Universe as we know it today.

Luckily for the research team, the massive, star-forming galaxies of this period are known to contain a great deal of dust. While very faint in the optical band, these galaxies emit strong radiation at submillimeter wavelengths, which makes them detectable using today’s advanced telescopes – including the South Pole Telescope (SPT), the Atacama Pathfinder Experiment (APEX), and Atacama Large Millimeter Array (ALMA).

*NASA’s Spitzer Space Telescope captured this stunning infrared image of the center of the Milky Way Galaxy, where the black hole Sagitarrius A resides. Image: NASA/JPL-Caltech*

For the sake of their study, Strandet and Weiss relied on data from the SPT to detect a series of dusty galaxies from the early Universe. As Maria Strandet and Axel Weiss of the Max Planck Institute for Radio Astronomy (and the lead author and co-authors on the study, respectively) told Universe Today via email:

“We have used light of about 1 mm wavelength, which can be observed by mm telescopes like SPT, APEX or ALMA. At this wavelength the photons are produced by the thermal radiation of dust. The beauty of using this long wavelength is, that for a large redshift range (look back time), the dimming of galaxies [caused] by increasing distance is compensated by the redshift – so the observed intensity is independent of the redshift. This is because, for higher redshift galaxies, one is looking at intrinsically shorter wavelengths (by (1+z)) where the radiation is stronger for a thermal spectrum like the dust spectrum.”

This was followed by data from ALMA, which the team used to determine the distance of the galaxies by looking at the redshifted wavelength of carbon monoxide molecules in their interstellar mediums (ISM). From all the data they collected, they were able to constrain the properties of one of these galaxies – SPT0311-58 – by observing its spectral lines. In so doing, they determined that this galaxy existed just 760 million years after the Big Bang.

“Since the signal strength at 1mm is independent of the redshift (look back time), we do not have an a priori clue if an object is relatively near (in the cosmological sense) or at the epoch of reionization,” they said. “That is why we undertook a large survey to determine the redshifts via the emission of molecular lines using ALMA. SPT0311-58 turns out to be the highest redshift object discovered in this survey and in fact the most distant massive dusty star-forming galaxy so far discovered.”

The Hubble Ultra Deep Field seen in ultraviolet, visible, and infrared light. Image Credit: NASA, ESA, H. Teplitz and M. Rafelski (IPAC/Caltech), A. Koekemoer (STScI), R. Windhorst (Arizona State University), and Z. Levay (STScI)

From their observations, they also determined that SPT0311-58 has a mass of about 330 billion Solar-masses, which is about 66 times as much as the Milky Way Galaxy (which has about 5 billion Solar-masses). They also estimated that it is forming new stars at a rate of several thousand per year, which could as be the case for neighboring galaxies that are dated to this period.

This rare and distant object is one of the best candidates yet for studying what the early Universe looked like and how it has evolved since. This in turn will allow astronomers and cosmologists to test the theoretical basis for the Big Bang Theory. As Strandet and Weiss told Universe Today about their discovery:

“These objects are important to understanding the evolution of galaxies as a whole since the large amounts of dust already present in this source, only 760 million years after the Big Bang, means that it is an extremely massive object. The mere fact that such massive galaxies already existed when the Universe was still so young puts strong constraints on our understanding of galaxy mass buildup. Furthermore the dust needs to form in a very short time, which gives additional insights on the dust production from the first stellar population.”

The ability to look deeper into space, and farther back in time, has led to many surprising discoveries of late. And these have in turn challenged some of our assumptions about what happened in the Universe, and when. And in the end, they are helping scientists to create a more detailed and complete account of cosmic evolution. Someday soon, we might even be able to probe the earliest moments in the Universe, and watch creation in action!

Further Reading: CfA, The Astrophysical Journal Letters

August 16, 2017 by Susie Murph

Carnival of Space #522

Carnival of Space. Image by Jason Major.

This week’s Carnival of Space is hosted by Brian Wang at his Next Big Future blog.

Click here to read Carnival of Space #522
Continue reading “Carnival of Space #522”

August 15, 2017 by Matt Williams

Potentially Habitable, Tidally-Locked Exoplanets May be Very Common, say New Study

Artist's impression of a system of exoplanets orbiting a low mass, red dwarf star. Credit: NASA/JPL

Studies of low-mass, ultra-cool and ultra-dim red dwarf stars have turned up a wealth of extra-solar planets lately. These include the discoveries of a rocky planet orbiting the closest star to the Solar System (Proxima b) and a seven-planet system just 40 light years away (TRAPPIST-1). In the past few years, astronomers have also detected candidates orbiting the stars Gliese 581, Innes Star, Kepler 42, Gliese 832, Gliese 667, Gliese 3293, and others.

The majority of these planets have been terrestrial (i.e. rocky) in nature, and many were found to orbit within their star’s habitable zone (aka. “goldilocks zone”). However the question whether or not these planets are tidally-locked, where one face is constantly facing towards their star has been an ongoing one. And according to a new study from the University of Washington, tidally-locked planets may be more common than previously thought.

The study – which is available online under the title “Tidal Locking of Habitable Exoplanets” – was led by Rory Barnes, an assistant professor of astronomy and astrobiology at the University of Washington. Also a theorist with the Virtual Planetary Laboratory, his research is focused on the formation and evolution of planets that orbit in and around the “habitable zones” of low-mass stars.

*Tidal locking results in the Moon rotating about its axis in about the same time it takes to orbit the Earth (left side). Credit: Wikipedia*

For modern astronomers, tidal-locking is a well-understood phenomena. It occurs as a result of their being no net transfer of angular momentum between an astronomical body and the body it orbits. In other words, the orbiting body’s orbital period matches its rotational period, ensuring that the same side of this body is always facing towards the planet or star it orbits.

Consider Earth’s only satellite – the Moon. In addition to taking 27.32 days to orbit Earth, the Moon also takes 27.32 days to rotate once on its axis. This is why the Moon always presents the same “face” towards Earth, while the side that faces away is known as the “dark side”. Astronomers believe this became the case after a Mars-sized object (Theia) collided with Earth some 4.5 billion years ago.

Aside from throwing up debris that would eventually form the Moon, the impact is believed to have struck Earth at such an angle that it gave our planet an initial rotation period of 12 hours. In the past, researchers have used this 12-hour estimation of Earth’s rotation as a model for exoplanet behavior. However, prior to Barnes’ study, no systematic examinations had ever been conducted.

Looking to address this, Barnes chose to address the long-held assumption that only smaller, dimmer stars could host orbiting planets that were tidally locked. He also considered other possibilities, which included slower or faster initial rotation periods as well as variations in planet size and the eccentricity of their orbits. What he found was that previous studies had been rather limited and only made allowances for one outcome.

*Tidally-locked, rocky planets are common around low-mass, M-type (red dwarf) stars, due to their close orbits. Credit: M. Weiss/CfA*

As he explained in a University of Washington press statement:

“Planetary formation models, however, suggest the initial rotation of a planet could be much larger than several hours, perhaps even several weeks. And so when you explore that range, what you find is that there’s a possibility for a lot more exoplanets to be tidally locked. For example, if Earth formed with no Moon and with an initial ‘day’ that was four days long, one model predicts Earth would be tidally locked to the sun by now.”

From this, he found that potentially-habitable planets that orbit very late M-type (red dwarf) stars are likely to attain highly-circular orbits about 1 billion years after their formation. Furthermore, he found that for the majority, their orbits would be synchronized with their rotation – aka. they would be tidally-locked with their star. These findings could have significant implications for the study of exoplanets formation and evolution, not to mention habitability.

In the past, tidally-locked planets were thought to have extremes climates, thus eliminating any possibility of life. As an example, the planet Mercury experiences a 3:2 spin-orbit resonance, meaning it rotates three times on its axis for every two orbits it completes of the Sun. Because of this, a single day on Mercury lasts as long as 176 Earth days, and temperature range from 100 (-173 °C; -279 °F) to 700 K (427 °C; 800 °F) between the day side and the night side.

For a tidally-locked planets that orbit close to their stars, it was believed this situation would be even worse. However, astronomers have since come to speculate that the presence of an atmosphere around these planets could redistribute temperature across their surfaces. Unlike Mercury, which has no atmosphere and experiences no wind, these planets could maintain temperatures that would be supportive to life.

*Artist’s impression of a “Earth-like” planet orbiting a nearby red dwarf star. Credit: ESO/M. Kornmesser/N. Risinger (skysurvey.org).*

In any case, this study is one of many that is putting constraints on recent exoplanet discoveries. This is especially important given that the detection and study of extra-solar planets is still in its infancy, and limited to largely indirect methods. In other words, astronomers make estimates of a planet’s size, composition and whether or not it has an atmosphere based on transits and the influence these planets have on their stars.

In the coming years, next-generations missions like the James Web Space Telescope and the Transiting Exoplanet Survey Satellites (TESS) are expected to improve this situation drastically. In addition to conducting more detailed observations on existing discoveries, they are also expected to uncover a wealth of more planets. If Barnes’ study is correct, the majority of those found will be tidally-locked, but that need not mean they are uninhabitable.

Prof. Barnes paper was accepted for publication by the journal Celestial Mechanics and Dynamical Astronomy. The research was funded by a NASA grant through the Virtual Planetary Laboratory.

Further Reading: University of Washington, arXiv

August 14, 2017August 15, 2017 by Ken Kremer

Stunning SpaceX Space Station Cargo Blastoff and Cape Landing Kicks Off Sunshine State Liftoff Trio

KENNEDY SPACE CENTER, FL – Todays (Aug. 14) stunning SpaceX Space Station cargo delivery blastoff to the International Space Station (ISS) and flawless first stage landing from the Kennedy Space Center and Cape Canaveral Air Force Station in the Sunshine State kicked off a rapid fire sequence of liftoffs planned for mid August.

All 9 SpaceX Falcon 9 Merlin 1D first stage engines ignited precisely on time from seaside pad 39A at NASA’s Kennedy Space Center in Florida today (Aug. 14) at 12:31 p.m. EDT (1631 GMT).

“It was a gorgeous day and a specular launch,” said Dan Hartman, NASA deputy manager of the International Space Station Program, at the post launch briefing at the Kennedy Space Center press site.

The 9 Merlin 1D’s of the two stage 213-foot-tall (65-meter-tall) Falcon 9 generate 1.7 million pounds of liftoff thrust fueled by liquid oxygen and RP-1 propellants.

“Just greatness to report about the launch,” said Hans Koenigsmann, SpaceX vice president of Flight and Build Reliability at the post launch briefing.

“The second stage deployed Dragon to a near perfect orbit. The first stage was successful and made a perfect landing. From what I’ve heard, it’s right on the bullseye and made a very soft touchdown, so it’s a great pre-flown booster ready to go for the next time.”

So its 1 down and 2 launches to go along the Florida Space Coast over the next 11 days of manmade wonder – Plus a Total Solar ‘Eclipse Across America’ natural wonder sandwiched in between !!

“We’re excited that about three quarters of the payload aboard is science,” noted Hartman. “With the internal and external payloads that we have going up, it sets a new bar for the amount of research that we’ve been able to get on this flight.”

And all 6 astronauts and cosmonauts serving aboard the station are especially looking forward to unpacking and serving up a specially cooled and hefty stash of delicious ice cream!

The ice cream, medical experiments and mice were all part of the late load items added the evening before liftoff – work that was delayed due to thunderstorms and completed just in time to avoid a launch delay.

A huge crowd of delighted locals, tourists and folks flocking in from around the globe, packed local beaches, causeways and parks and the Kennedy Space Center and witnessed a space launch and landing spectacular they will long remember.

The Dragon resupply ship dubbed Dragon CRS-12 counts as SpaceX’s twelfth contracted commercial resupply services (CRS) mission to the International Space Station for NASA since 2012.

The launch and landing of the SpaceX Falcon 9 booster took place just minutes apart under near perfect weather conditions, as the Dragon capsule sped to the heavens on a mission to the High Frontier of Space.

The 22 story Falcon 9 roared off pad 39A on a stream of flames and exhaust into blue skies decorated with artfully spaced wispy clouds that enhanced the viewing experience as the rocket accelerated to orbit and on its way to the 6 person multinational crew.

The triple headed sunshine state space spectacular marches forward in barely 4 days with liftoff of NASA’s amazingly insectoid-looking TDRS-M science relay comsat slated for Friday morning Aug. 18 atop a United Launch Alliance (ULA) Atlas V rocket.

Lastly, a week after TDRS-M and just 11 days after the SpaceX Dragon an Orbital ATK Minotaur 4 rocket is due to blastoff just before midnight Aug. 25 and carry the ORS 5 mission to orbit for the U.S. military’s Operationally Responsive Space program. The Minotaur IV utilizes three stages from decommissioned Peacekeeper ICBMs formerly aimed at the Russians and perhaps the North Koreans.

The Total Solar ‘Eclipse Across America’ takes place on Monday, Aug. 21. It’s the first solar eclipse in 99 years that space the continent from coast to coast and will be at least partially visible in all 48 contiguous states!

20 mice are also onboard from NASA for the Rodent Research 9 (RR-9) experiment and another dozen from Japanese researchers. This will support more than 80 of the 250 research investigations and experiments being conducted by Expedition 52 and 53 crew members.

Dragon reached its preliminary orbit about 10 minutes later and successfully deployed its life giving solar arrays.

Dragon CRS-12 now begins a 2 day orbital chase of the station via a carefully choreographed series of thruster firings that bring the commercial spacecraft to rendezvous with the space station on Aug. 16.

Dragon will be grappled with the station’s 57.7-foot-long (17.6 meter-long) Canadian-built robotic arm at approximately 7 a.m. EDT on Aug. 16 by astronauts Jack Fischer of NASA and Paolo Nespoli of ESA (European Space Agency). It then will be installed on the Harmony module.

The Dragon spacecraft will spend approximately 35 days attached to the space station, returning to Earth in mid-September with over 3000 pounds of science samples and results gathered over many months from earlier experiments by the station crews.

Dragon CRS-12 is SpaceX’s third contracted resupply mission to launch this year for NASA.

The prior SpaceX cargo ships launched on Feb 19 and June 3, 2017 on the CRS-10 and CRS-11 missions to the space station. CRS-10 is further noteworthy as being the first SpaceX launch of a Falcon 9 from NASA’s historic pad 39A.

A fourth cargo Dragon is likely to launch this year in December on the CRS-13 resupply mission under NASA’s current plans.

SpaceX leased pad 39A from NASA in 2014 and after refurbishments placed the pad back in service this year for the first time since the retirement of the space shuttles in 2011.

Previous launches include 11 Apollo flights, the launch of the unmanned Skylab in 1973, 82 shuttle flights and five SpaceX launches.

Cargo Manifest for CRS-12:

TOTAL CARGO: 6415.4 lbs. / 2910 kg
TOTAL PRESSURIZED CARGO WITH PACKAGING: 3642 lbs. / 1652 kg
• Science Investigations 2019.4 lbs. / 916 kg
• Crew Supplies 485 lbs. / 220 kg
• Vehicle Hardware 747.4 lbs. / 339 kg
• Spacewalk Equipment 66.1 lbs. / 30 kg
• Computer Resources 116.8 lbs. / 53 kg

UNPRESSURIZED 2773.4 lbs. / 1258 kg
• Cosmic-Ray Energetics and Mass (CREAM) 2773.4 lbs. / 1258 kg

The CREAM instrument from the University of Maryland will be stowed for launch inside the Dragon’s unpressurized trunk. Astronauts will use the stations robotic arm to pluck it from the trunk and attach it to a US port on the exposed porch of the Japanese Experiment Module (JEM).

CREAM alone comprises almost half the payload weight.

The Cosmic-Ray Energetics and Mass investigation (CREAM) instrument from the University of Maryland, College Park involves placing a balloon-borne instrument aboard the International Space Station to measure the charges of cosmic rays over a period of three years. CREAM will be attached to the Japanese Experiment Module Exposed Facility. Existing CREAM hardware used for balloon flights. Credit: NASA

Here is a NASA description of CREAM:

The Cosmic Ray Energetics and Mass (CREAM) instrument will be attached to the Japanese Experiment Module Exposed Facility on the space station, and measure the charges of cosmic rays. The data collected from its three-year mission will address fundamental questions about the origins and histories of cosmic rays, building a stronger understanding of the basic structure of the universe.

The LRRK2 experiment seeks to grow larger crystals of the protein to investigate Parkinson’s disease and help develop new therapies:

Here is a NASA description of LRRK2:

The Dragon’s pressurized area includes an experiment to grow large crystals of leucine-rich repeat kinase 2 (LRRK2), a protein believed to be the greatest genetic contributor to Parkinson’s disease. Gravity keeps Earth-grown versions of this protein too small and too compact to study. This experiment, developed by the Michael J. Fox Foundation, Anatrace and Com-Pac International, will exploit the benefits of microgravity to grow larger, more perfectly-shaped LRRK2 crystals for analysis on Earth. Results from this study could help scientists better understand Parkinson’s and aid in the development of therapies.

Watch this Michael J. Fox video describing the LRRK2 crystallization experiment:

Watch for Ken’s continuing onsite CRS-12, TRDS-M, and ORS 5 and NASA mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.
Ken Kremer

SpaceX Falcon 9 rocket rests horizontally at Launch Complex 39A at the Kennedy Space Center on 13 Aug. 2017 while being processed for liftoff of the Dragon CRS-12 resupply mission to the International Space Station (ISS) slated for 14 Aug. 2017. Credit: Ken Kremer/Kenkremer.com

August 14, 2017August 15, 2017 by Tammy Plotner

Messier 54 – the NGC 6715 Globular Cluster

Hubble image of Messier 54, a globular cluster located in the Sagittarius Dwarf Galaxy. Credit: ESA/Hubble & NASA

Welcome back to Messier Monday! In our ongoing tribute to the great Tammy Plotner, we take a look at globular cluster known as Messier 54!

During the 18th century, famed French astronomer Charles Messier noted the presence of several “nebulous objects” in the night sky. Having originally mistaken them for comets, he began compiling a list of these objects so others would not make the same mistake he did. In time, this list (known as the Messier Catalog) would come to include 100 of the most fabulous objects in the night sky.

One of these objects is the globular cluster known as Messier 54. Located in the direction of the Sagittarius constellation, this cluster was once thought to be part of the Milky Way, located about 50,000 light years from Earth, In recent decades, astronomers have come to realize that it is actually part of the Sagittarius Dwarf Galaxy, located some 87,000 light-years away.

What You Are Looking At:

Running away from us at a speed of 142 kilometers per second, this compact globe of stars could be as wide as 150 light years in diameter and as far away as 87,400 light years. Wait… Hold the press… Almost 90 thousand light years? Yeah. Messier 54 isn’t part of our own Milky Way Galaxy!

In 1994 astronomers made a rather shocking discovery… this tough to resolve globular was actually part of the Sagittarius Dwarf Elliptical Galaxy. As Michael H. Siegal (et al) said in their study:

“As part of the ACS Survey of Galactic Globular Clusters, we present new Hubble Space Telescope photometry of the massive globular cluster M54 (NGC 6715) and the superposed core of the tidally disrupted Sagittarius (Sgr) dSph galaxy. Our deep (F606W ~ 26.5), high-precision photometry yields an unprecedentedly detailed color-magnitude diagram showing the extended blue horizontal branch and multiple main sequences of the M54+Sgr system. Multiple turnoffs indicate the presence of at least two intermediate-aged star formation epochs with 4 and 6 Gyr ages and [Fe/H]=-0.4 to -0.6. We also clearly show, for the first time, a prominent, ~2.3 Gyr old Sgr population of near-solar abundance. A trace population of even younger (~0.1-0.8 Gyr old), more metal-rich ([Fe/H]~0.6) stars is also indicated. The Sgr age-metallicity relation is consistent with a closed-box model and multiple (4-5) star formation bursts over the entire life of the satellite, including the time since Sgr began disrupting.”

Inside its compact depths lurk at least 82 known variable stars – 55 of which are the RR Lyrae type. But astronomers using the Hubble Space telescope have have also discovered there are two semi-regular red variables with periods of 77 and 101 days. Kevin Charles Schlaufman and Kenneth John Mighell of the National Optical Astronomy Observatory explained in their study:

“Most of our candidate variable stars are found on the PC1 images of the cluster center – a region where no variables have been reported by previous ground-based studies of variables in M54. These observations cannot be done from the ground, even with AO as there are far too many stars per resolution element in ground-based observations.”

The globular cluster Messier 54. Credit: NASA

But what other kinds of unusual stars could be discovered inside such distant cosmic stellar evolutionary laboratory? Try a phenomena known as blue hook stars! As Alfred Rosenberg (et al) said in their study:

“We present BV photometry centered on the globular cluster M54 (NGC 6715). The color-magnitude diagram clearly shows a blue horizontal branch extending anomalously beyond the zero-age horizontal-branch theoretical models. These kinds of horizontal-branch stars (also called “blue hook” stars), which go beyond the lower limit of the envelope mass of canonical horizontal-branch hot stars, have so far been known to exist in only a few globular clusters: NGC 2808, Omega Centauri (NGC 5139), NGC 6273, and NGC 6388. Those clusters, like M54, are among the most luminous in our Galaxy, indicating a possible correlation between the existence of these types of horizontal-branch stars and the total mass of the cluster. A gap in the observed horizontal branch of M54 around Teff = 27,000 K could be interpreted within the late helium flash theoretical scenario, which is a possible explanation for the origin of blue hook stars.”

But with the stars packaged together so tightly, even more has been bound to occur inside of Messier 54. As Tim Adams (et al) indicated in their study:

“We investigate a means of explaining the apparent paucity of red giant stars within post-core-collapse globular clusters. We propose that collisions between the red giants and binary systems can lead to the destruction of some proportion of the red giant population, by either knocking out the core of the red giant or by forming a common envelope system which will lead to the dissipation of the red giant envelope. Treating the red giant as two point masses, one for the core and another for the envelope (with an appropriate force law to take account of the distribution of mass), and the components of the binary system also treated as point masses, we utilize a four-body code to calculate the time-scales on which the collisions will occur. We then perform a series of smooth particle hydrodynamics runs to examine the details of mass transfer within the system. In addition, we show that collisions between single stars and red giants lead to the formation of a common envelope system which will destroy the red giant star. We find that low-velocity collision between binary systems and red giants can lead to the destruction of up to 13 per cent of the red giant population. This could help to explain the colour gradients observed in PCC globular clusters. We also find that there is the possibility that binary systems formed through both sorts of collision could eventually come into contact perhaps producing a population of cataclysmic variables.”

*Messier 54, as imaged by the VLT Survey Telescope at ESO’s Paranal Observatory in northern Chile. Credit: ESO*

But the discoveries haven’t ended yet…. Because 2009 studies have revealed evidence for an intermediate mass black hole inside Messier 54 – the first known to have ever been discovered in a globular cluster.

“We report the detection of a stellar density cusp and a velocity dispersion increase in the center of the globular cluster M54, located at the center of the Sagittarius dwarf galaxy (Sgr). The central line-of-sight velocity dispersion is 20.2 ± 0.7 km s-1, decreasing to 16.4 ± 0.4 km s-1 at 2farcs5 (0.3 pc). Modeling the kinematics and surface density profiles as the sum of a King model and a point-mass yields a black hole mass of ~9400 M sun.” says R. Ibata (et al), “However, the observations can alternatively be explained if the cusp stars possess moderate radial anisotropy. A Jeans analysis of the Sgr nucleus reveals a strong tangential anisotropy, probably a relic from the formation of the system.”

History of Observation:

On July 24, 1778 when Charles Messier first laid eyes on this faint fuzzy, he had no clue that he was about to discover the very first extra-galactic globular cluster. In his notes he writes: “Very faint nebula, discovered in Sagittarius; its center is brilliant and it contains no star, seen with an achromatic telescope of 3.5 feet. Its position has been determined from Zeta Sagittarii, of 3rd magnitude.”

Years later Sir William Herschel would also study M54, and in his private notes he writes: “A round, resolvable nebula. Very bright in the middle and the brightness diminishing gradually, about 2 1/2′ or 3′ in diameter. 240 shews too pretty large stars in the faint part of the nebulosity, but I rather suppose them to have no connection with the nebula. I believe it to be no other than a miniature cluster of very compressed stars.”

Countless other observations would follow as the M54 became cataloged by other astronomers and each would in turn describe it only as having a much brighter core and some resolution around the edges. Have fun trying to crack this one!

Locating Messier 54:

M54 isn’t hard to find… Just skip down to Zeta Sagittarii, the southwestern-most star of Sagittarius “teapot” and hop a half degree south and a finger width (1.5 degrees) west. The problem is seeing it! In small optics, such as binoculars or a finder scope, it will appear almost stellar because of its small size. However, if you just look for what appears like a larger, dim star that won’t quite come into perfect focus, then you’ve found it.

In smaller telescopes, you’ll get no resolution on this class III globular cluster because it is so dense. Large aperture doesn’t fare much better either, with only some individual stars making their appearance at the outer perimeters. Because of magnitude and size, Messier 54 is better suited to dark sky conditions.

*The location of Messier 54 in the Sagittarius constellation. Credit: IAU/Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)*

And here are the quick facts on this Messier Object to help you get started:

Object Name: Messier 54
Alternative Designations: M54, NGC 6715
Object Type: Class III Extragalactic Globular Cluster
Constellation: Sagittarius
Right Ascension: 18 : 55.1 (h:m)
Declination: -30 : 29 (deg:m)
Distance: 87.4 (kly)
Visual Brightness: 7.6 (mag)
Apparent Dimension: 12.0 (arc min)

We have written many interesting articles about Messier Objects here at Universe Today. Here’s Tammy Plotner’s Introduction to the Messier Objects, , M1 – The Crab Nebula, M8 – The Lagoon Nebula, and David Dickison’s articles on the 2013 and 2014 Messier Marathons.

Be to sure to check out our complete Messier Catalog. And for more information, check out the SEDS Messier Database.

Sources:

August 14, 2017June 20, 2020 by Matt Williams

Scientists Discover TRAPPIST-1 is Older Than Our Solar System

Most exoplanets orbit red dwarf stars because they're the most plentiful stars. This is an artist's illustration of what the TRAPPIST-1 system might look like from a vantage point near planet TRAPPIST-1f (at right). Credits: NASA/JPL-Caltech

In February of 2017, a team of European astronomers announced the discovery of a seven-planet system orbiting the nearby star TRAPPIST-1. Aside from the fact that all seven planets were rocky, there was the added bonus of three of them orbiting within TRAPPIST-1’s habitable zone. As such, multiple studies have been conducted that have sought to determine whether or not any planets in the system could be habitable.

When it comes to habitability studies, one of the key factors to consider is the age of the star system. Basically, young stars have a tendency to flare up and release harmful bursts of radiation while planets that orbit older stars have been subject to radiation for longer periods of time. Thanks to a new study by a pair of astronomers, it is now known that the TRAPPIST-1 system is twice as old as the Solar System.

Continue reading “Scientists Discover TRAPPIST-1 is Older Than Our Solar System”

August 12, 2017August 14, 2017 by Ken Kremer

Science Laden SpaceX Dragon Set for Aug. 14 ISS Launch, Testfire Inaugurates Triad of August Florida Liftoffs: Watch Live

KENNEDY SPACE CENTER, FL – A triad of August liftoffs from the Florida Space Coast inaugurates Monday, Aug. 14 with a science laden commercial SpaceX Dragon bound for the International Space Station (ISS) – loaded with over 3 tons of NASA science, hardware and supplies including a cosmic ray detector, medical research experiments dealing with Parkinson’s disease and lung tissue, vegetable seeds, mice and much more, following a successful engine test firing of the Falcon 9 booster on Thursday.

“Static fire test of Falcon 9 complete,” SpaceX confirmed via Twitter soon after completion of the test at 9:10 a.m. EDT, Aug 10. (1310 GMT) “—targeting August 14 launch from Pad 39A for Dragon’s next resupply mission to the @Space_Station.”

Check out our photos & videos herein of the Aug. 10 static first test of the Falcon 9 first stage that paves the path to blastoff – as witnessed live by Ken Kremer and Jeff Seibert.

The triple headed sunshine state space spectacular kicks off with Monday’s lunchtime launch of the next unmanned SpaceX Dragon cargo freighter to the ISS from seaside pad 39A at NASA’s Kennedy Space Center in Florida, now targeted for Aug. 14 at 12:31 p.m. EDT (1631 GMT).

The closely spaced trio of space launches marches forward barely 4 days later with liftoff of NASA’s amazingly insectoid-looking TDRS-M science relay comsat slated for Friday morning Aug. 18 atop a United Launch Alliance (ULA) Atlas V rocket.

Of course getting 3 rockets off the ground from 3 different companies is all highly dependent on Florida’s hugely fickle hurricane season weather and the ever present reality of potential technical glitches, errant boaters and more – possibly resulting in a domino effect of cascading launch scrubs.

And sandwiched in between the Florida Space Coast blastoffs is the Total Solar ‘Eclipse Across America’ on Monday, Aug. 21 – for the first time in 99 years!

Although KSC and central Florida are not within the path of totality, the sun will still be about 85% obscured by the Moon.

So if you’re looking for bang for the space buck, the next two weeks have a lot to offer space and astronomy enthusiasts.

1st Reused SpaceX Dragon cargo craft lifts off from Launch Complex 39A at NASA’s Kennedy Space Center in Florida at 5:07 p.m. June 3, 2017 on CRS-11 mission carrying 3 tons of research equipment, cargo and supplies to the International Space Station. Credit: Ken Kremer/kenkremer.com

The Dragon resupply ship dubbed Dragon CRS-12 counts as SpaceX’s twelfth contracted commercial resupply services (CRS) mission to the International Space Station for NASA since 2012.

SpaceX conducts successful static fire test of the Falcon 9 rocket on Aug. 10, 2017 at Launch Complex 39A on NASA’s Kennedy Space Center, Fl as seen from Playalinda causeway. Liftoff of the uncrewed Dragon CRS-12 resupply mission for NASA to the International Space Station (ISS) is scheduled for Aug. 14, 2017. Credit: Ken Kremer/kenkremer.com

Watch this video of the Aug. 10 static hotfire test:

Video Caption: Hot fire test of the SpaceX Falcon 9 rocket in preparation for it launching the NASA CRS-12 Dragon resupply mission to the International Space Station from Pad 39A at Kennedy Space Center in Florida. Credit: Jeff Seibert/AmericaSpace

If you can’t personally be here to witness the launch in Florida, you can always watch NASA’s live coverage on NASA Television and the agency’s website.

The SpaceX/Dragon CRS-12 launch coverage will be broadcast on NASA TV beginning noon on Aug. 14 with additional commentary on the NASA launch blog.

SpaceX will also offer their own live webcast beginning approximately 15 minutes before launch at about 12:16 p.m. EDT.

You can watch the launch live at NASA TV at – http://www.nasa.gov/nasatv

You can also watch the launch live at SpaceX hosted Webcast at – spacex.com/webcast

In the event of delay for any reason, the next launch opportunity is Tuesday, Aug. 15 with NASA TV coverage starting about 11:30 a.m. EDT.

The weather looks decent at this time with a 70% chance of favorable conditions at launch time according to U.S. Air Force meteorologists with the 45th Space Wing Weather Squadron at Patrick Air Force Base. The primary concerns on Aug. 14 are cumulus clouds and the potential for precipitation in the flight path.

The odds remain at 70% favorable for the 24 hour scrub turnaround day on Aug. 15.

Everything is currently on track for Monday’s noontime launch of the 230 foot tall SpaceX Falcon 9 on the NASA contracted SpaceX CRS-12 resupply mission to the million pound orbiting lab complex.

However since the launch window is instantaneous there is no margin for error. In case any delays arise during the countdown due to technical or weather issues a 24 hour scrub to Tuesday will result.

The lunchtime launch coincidently offers a convenient and spectacular opportunity for fun for the whole family as space enthusiasts flock in from around the globe.

Plus SpaceX will attempt a land landing of the 156 foot tall first stage back at the Cape at Landing Zone 1 some 8 minutes after liftoff – thus a double whammy of space action !!– punctuated by multiple loud sonic booms at booster landing time that will figuratively knock your socks off.

SpaceX Falcon 9 booster deploys quartet of landing legs moments before precision propulsive ground touchdown at Landing Zone 1 on Canaveral Air Force Station barely nine minutes after liftoff from Launch Complex 39A on 3 June 2017 from the Kennedy Space Center in Florida on the Dragon CRS-11 resupply mission to the International Space Station for NASA. Credit: Ken Kremer/Kenkremer.com

To date SpaceX has successfully recovered 13 boosters; 5 by land and 8 by sea, over the past 18 months. It’s a feat straight out of science fiction but aimed at drastically slashing the high cost of access to space.

The recent BulgariaSat-1 and Iridium-2 missions counted as the eighth and ninth SpaceX launches of 2017.

CRS-12 marks the eleventh SpaceX launch of 2017 and will establish a new single year record.

In contrast to the prior CRS-11 mission which flew a recycled Dragon, the CRS-12 Dragon is newly built.

The CRS-12 Dragon will be the last newly built one, says NASA. The remaining SpaceX CRS mission will utilize reused spaceships.

The Falcon 9 is also new and will attempt a land landing back at the Cape at Landing Zone-1 (LZ-1).

If the Aug. 14 launch occurs as scheduled, the Dragon will reach its preliminary orbit about 10 minutes later and deploy its life giving solar arrays. Dragon then begins a 2 day orbital chase of the station via a carefully choreographed series of thruster firings that bring the commercial spacecraft to rendezvous with the space station on Aug. 16.

Dragon will be grappled with the station’s Canadian built robotic arm at approximately 7 a.m. EDT on Aug. 16 by astronauts Jack Fischer of NASA and Paolo Nespoli of ESA (European Space Agency). It then will be installed on the Harmony module.

The Dragon spacecraft will spend approximately one month attached to the space station, returning to Earth in mid-September with results of earlier experiments.

Dragon CRS-12 is SpaceX’s third contracted resupply mission to launch this year for NASA.

SpaceX leased pad 39A from NASA in 2014 and after refurbishments placed the pad back in service this year for the first time since the retirement of the space shuttles in 2011.

Previous launches include 11 Apollo flights, the launch of the unmanned Skylab in 1973, 82 shuttle flights and five SpaceX launches.

Cargo Manifest for CRS-12:

TOTAL CARGO: 6415.4 lbs. / 2910 kg

TOTAL PRESSURIZED CARGO WITH PACKAGING: 3642 lbs. / 1652 kg
• Science Investigations 2019.4 lbs. / 916 kg
• Crew Supplies 485 lbs. / 220 kg
• Vehicle Hardware 747.4 lbs. / 339 kg
• Spacewalk Equipment 66.1 lbs. / 30 kg
• Computer Resources 116.8 lbs. / 53 kg

UNPRESSURIZED 2773.4 lbs. / 1258 kg
• Cosmic-Ray Energetics and Mass (CREAM) 2773.4 lbs. / 1258 kg

The CREAM instrument from the University of Maryland will be stowed for launch inside the Dragon’s unpressurized trunk. Astronauts will use the stations robotic arm to pluck it from the trunk and attach it to the exposed porch of the Japanese Experiment Module (JEM).

Here is a NASA description of CREAM:

The Cosmic Ray Energetics and Mass (CREAM) instrument, attached to the Japanese Experiment Module Exposed Facility, measures the charges of cosmic rays ranging from hydrogen to iron nuclei. The data collected from the CREAM instrument will be used to address fundamental science questions on the origins and history of cosmic rays. CREAM’s three-year mission will help the scientific community build a stronger understanding of the fundamental structure of the universe.

The LRRK2 experiment seeks to grow larger crystals of the protein to investigate Parkinson’s disease and help develop new therapies:

Here is a NASA description of LRRK2:

Crystallization of Leucine-rich repeat kinase 2 (LRRK2) under Microgravity Conditions (CASIS PCG 7) will use the orbiting laboratory’s microgravity environment to grow larger versions of this important protein, implicated in Parkinson’s disease. Developed by the Michael J. Fox Foundation, Anatrace and Com-Pac International, researchers will look to take advantage of the station’s microgravity environment which allows protein crystals to grow larger and in more perfect shapes than earth-grown crystals, allowing them to be better analyzed on Earth. Defining the exact shape and morphology of LRRK2 would help scientists to better understand the pathology of Parkinson’s and aid in the development of therapies against this target.

Watch this Michael J. Fox video describing the LRRK2 crystallization experiment:

Video Caption: ISS National Lab SpaceX CRS-12 Payload Overview: Michael J. Fox Foundation. The Michael J. Fox Foundation is sending an experiment to the ISS National Lab to investigate the LRRK2 protein, a key target in identifying the makeup of Parkinson’s disease.

Watch for Ken’s continuing onsite CRS-12, TRDS-M, and ORS 5 and NASA mission reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station, Florida.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

………….

Learn more about the upcoming SpaceX Dragon CRS-12 resupply launch to ISS on Aug. 14, ULA Atlas TDRS-M NASA comsat on Aug. 18, 2017 Solar Eclipse, NASA missions and more at Ken’s upcoming outreach events at Kennedy Space Center Quality Inn, Titusville, FL:

Aug 12-14: “SpaceX CRS-12 resupply launches to the ISS, Intelsat35e, BulgariaSat 1 and NRO Spysat, SLS, Orion, Commercial crew capsules from Boeing and SpaceX , Heroes and Legends at KSCVC, ULA Atlas/John Glenn Cygnus launch to ISS, SBIRS GEO 3 launch, GOES-R weather satellite launch, OSIRIS-Rex, Juno at Jupiter, InSight Mars lander, SpaceX and Orbital ATK cargo missions to the ISS, ULA Delta 4 Heavy spy satellite, Curiosity and Opportunity explore Mars, Pluto and more,” Kennedy Space Center Quality Inn, Titusville, FL, evenings

Up close view of SpaceX Dragon CRS-11 resupply vessel atop Falcon 9 rocket and delivering 3 tons of science and supplies to the International Space Station (ISS) for NASA. Liftoff occurred 3 June 2017. Credit: Ken Kremer/Kenkremer.com

Inside the Astrotech payload processing facility in Titusville, FL,NASA’s massive, insect like Tracking and Data Relay Satellite, or TDRS-M, spacecraft is undergoing preflight processing during media visit on 13 July 2017. TDRS-M will transmit critical science data gathered by the ISS, Hubble and numerous NASA Earth science missions. It is being prepared for encapsulation inside its payload fairing prior to being transported to Launch Complex 41 at Cape Canaveral Air Force Station for launch on a United Launch Alliance (ULA) Atlas V rocket on 3 August 2017. Credit: Ken Kremer/kenkremer.com

August 11, 2017July 27, 2023 by Matt Williams

NASA Reignites Program for Nuclear Thermal Rockets

Artist's concept of a bimodal nuclear rocket making the journey to the Moon, Mars, and other destinations in the Solar System. Credit: NASA

In its pursuit of missions that will take us back to the Moon, to Mars, and beyond, NASA has been exploring a number of next-generation propulsion concepts. Whereas existing concepts have their advantages – chemical rockets have high energy density and ion engines are very fuel-efficient – our hopes for the future hinge on us finding alternatives that combine efficiency and power.

To this end, researchers at NASA’s Marshall Space Flight Center are once again looking to develop nuclear rockets. As part of NASA’s Game Changing Development Program, the Nuclear Thermal Propulsion (NTP) project would see the creation of high-efficiency spacecraft that would be capable of using less fuel to deliver heavy payloads to distant planets, and in a relatively short amount of time.

As Sonny Mitchell, the project of the NTP project at NASA’s Marshall Space Flight Center, said in a recent NASA press statement:

“As we push out into the solar system, nuclear propulsion may offer the only truly viable technology option to extend human reach to the surface of Mars and to worlds beyond. We’re excited to be working on technologies that could open up deep space for human exploration.”

*Nuclear reactors (like the one pictured here) are being considered by NASA’s Marshall Space Flight Center for possible future missions. Credit: NASA*

To see this through, NASA has entered into a partnership with BWX Technologies (BWXT), a Virginia-based energy and technology company that is a leading supplier of nuclear components and fuel to the U.S. government. To assist NASA in developing the necessary reactors that would support possible future crewed missions to Mars, the company’s subsidiary (BWXT Nuclear Energy, Inc.) was awarded a three-year contract worth $18.8 million.

During this three years in which they will be working with NASA, BWXT will provide the technical and programmatic data needed to implement NTP technology. This will consist of them manufacturing and testing prototype fuel elements and helping NASA to resolve any nuclear licensing and regulatory requirements. BWXT will also aid NASA planners in addressing the issues of feasibility and affordably with their NTP program.

As Rex D. Geveden, BWXT’s President and Chief Executive Officer, said of the agreement:

“BWXT is extremely pleased to be working with NASA on this exciting nuclear space program in support of the Mars mission. We are uniquely qualified to design, develop and manufacture the reactor and fuel for a nuclear-powered spacecraft. This is an opportune time to pivot our capabilities into the space market where we see long-term growth opportunities in nuclear propulsion and nuclear surface power.”

In an NTP rocket, uranium or deuterium reactions are used to heat liquid hydrogen inside a reactor, turning it into ionized hydrogen gas (plasma), which is then channeled through a rocket nozzle to generate thrust. A second possible method, known as Nuclear Electric Propulsion (NEC), involves the same basic reactor converted its heat and energy into electrical energy which then powers an electrical engine.

*Artist’s concept of a Bimodal Nuclear Thermal Rocket in Low Earth Orbit. Credit: NASA*

In both cases, the rocket relies on nuclear fission to generates propulsion rather than chemical propellants, which has been the mainstay of NASA and all other space agencies to date. Compared to this traditional form of propulsion, both types of nuclear engines offers a number of advantages. The first and most obvious is the virtually unlimited energy density it offers compared to rocket fuel.

This would cut the total amount of propellant needed, thus cutting launch weight and the cost of individual missions. A more powerful nuclear engine would mean reduced trip times. Already, NASA has estimated that an NTP system could make the voyage to Mars to four months instead of six, which would reduce the amount of radiation the astronauts would be exposed to in the course of their journey.

To be fair, the concept of using nuclear rockets to explore the Universe is not new. In fact, NASA has explored the possibility of nuclear propulsion extensively under the Space Nuclear Propulsion Office. In fact, between 1959 and 1972, the SNPO conducted 23 reactor tests at the Nuclear Rocket Development Station at AEC’s Nevada Test Site, in Jackass Flats, Nevada.

In 1963, the SNPO also created the Nuclear Engine for Rocket Vehicle Applications (NERVA) program to develop nuclear-thermal propulsion for long-range crewed mission to the Moon and interplanetary space. This led to the creation of the NRX/XE, a nuclear-thermal engine which the SNPO certified as having met the requirements for a crewed mission to Mars.

*Artist’s concept of a bimodal nuclear rocket slowing down to establish orbit around Mars. Credit: NASA*

The Soviet Union conducted similar studies during the 1960s, hoping to use them on the upper stages of of their N-1 rocket. Despite these efforts, no nuclear rockets ever entered service, owing to a combination of budget cuts, loss of public interest, and a general winding down of the Space Race after the Apollo program was complete.

But given the current interest in space exploration, and ambitious mission proposed to Mars and beyond, it seems that nuclear rockets may finally see service. One popular idea that is being considered is a multistage rocket that would rely on both a nuclear engine and conventional thrusters – a concept known as a “bimodal spacecraft”. A major proponent of this idea is Dr. Michael G. Houts of the NASA Marshall Space Flight Center.

In 2014, Dr. Houts conducted a presentation outlining how bimodal rockets (and other nuclear concepts) represented “game-changing technologies for space exploration”. As an example, he explained how the Space Launch System (SLS) – a key technology in NASA’s proposed crewed mission to Mars – could be equipped with chemical rocket in the lower stage and a nuclear-thermal engine on the upper stage.

In this setup, the nuclear engine would remain “cold” until the rocket had achieved orbit, at which point the upper stage would be deployed and the reactor would be activated to generate thrust. Other examples cited in the report include long-range satellites that could explore the Outer Solar System and Kuiper Belt and fast, efficient transportation for manned missions throughout the Solar System.

The company’s new contract is expected to run through Sept. 30th, 2019. At that time, the Nuclear Thermal Propulsion project will determine the feasibility of using low-enriched uranium fuel. After that, the project then will spend a year testing and refining its ability to manufacture the necessary fuel elements. If all goes well, we can expect that NASA’s “Journey to Mars” might just incorporate some nuclear engines!

Further Reading: NASA, BWXT News

August 11, 2017August 11, 2017 by Matt Williams

Cosmic Census Says There Could be 100 Million Black Holes in our Galaxy Alone

Artist's conception shows two merging black holes similar to those detected by LIGO on January 4th, 2017. Credit: LIGO/Caltech

In January of 2016, researchers at the Laser Interferometer Gravitational-Wave Observatory (LIGO) made history when they announced the first-ever detection of gravitational waves. Supported by the National Science Foundation (NSF) and operated by Caltech and MIT, LIGO is dedicated to studying the waves predicted by Einstein’s Theory of General Relativity and caused by black hole mergers.

According to a new study by a team of astronomers from the Center of Cosmology at the University of California Irvine, such mergers are far more common than we thought. After conducting a survey of the cosmos intended to calculate and categorize black holes, the UCI team determined that there could be as many as 100 million black holes in the galaxy, a finding which has significant implications for the study of gravitational waves.

The study which details their findings, titled “Counting Black Holes: The Cosmic Stellar Remnant Population and Implications for LIGO“, recently appeared in the Monthly Notices of the Royal Astronomical Society. Led by Oliver D. Elbert, a postdoc student with the department of Physics and Astronomy at UC Irvine, the team conducted an analysis of gravitational wave signals that have been detected by LIGO.

*LIGO’s two facilities, located in Livingston, Louisiana, and Hanford, Washington. Credit: ligo.caltech.edu*

Their study began roughly a year and a half ago, shortly after LIGO announced the first detection of gravitational waves. These waves were created by the merger of two distant black holes, each of which was equivalent in mass to about 30 Suns. As James Bullock, a professor of physics and astronomy at UC Irvine and a co-author on the paper, explained in a UCI press release:

“Fundamentally, the detection of gravitational waves was a huge deal, as it was a confirmation of a key prediction of Einstein’s general theory of relativity. But then we looked closer at the astrophysics of the actual result, a merger of two 30-solar-mass black holes. That was simply astounding and had us asking, ‘How common are black holes of this size, and how often do they merge?’”

Traditionally, astronomers have been of the opinion that black holes would typically be about the same mass as our Sun. As such, they sought to interpret the multiple gravitational wave detections made by LIGO in terms of what is known about galaxy formation. Beyond this, they also sought to create a framework for predicting future black hole mergers.

From this, they concluded that the Milky Way Galaxy would be home to up to 100 million black holes, 10 millions of which would have an estimated mass of about 30 Solar masses – i.e. similar to those that merged and created the first gravitational waves detected by LIGO in 2016. Meanwhile, dwarf galaxies – like the Draco Dwarf, which orbits at a distance of about 250,000 ly from the center of our galaxy – would host about 100 black holes.

They further determined that today, most low-mass black holes (~10 Solar masses) reside within galaxies of 1 trillion Solar masses (massive galaxies) while massive black holes (~50 Solar masses) reside within galaxies that have about 10 billion Solar masses (i.e. dwarf galaxies). After considering the relationship between galaxy mass and stellar metallicity, they interpreted a galaxy’s black hole count as a function of its stellar mass.

In addition, they also sought to determine how often black holes occur in pairs, how often they merge and how long this would take. Their analysis indicated that only a tiny fraction of black holes would need to be involved in mergers to accommodate what LIGO observed. It also offered predictions that showed how even larger black holes could be merging within the next decade.

As Manoj Kaplinghat, also a UCI professor of physics and astronomy and the second co-author on the study, explained:

“We show that only 0.1 to 1 percent of the black holes formed have to merge to explain what LIGO saw. Of course, the black holes have to get close enough to merge in a reasonable time, which is an open problem… If the current ideas about stellar evolution are right, then our calculations indicate that mergers of even 50-solar-mass black holes will be detected in a few years.”

In other words, our galaxy could be teeming with black holes, and mergers could be happening in a regular basis (relative to cosmological timescales). As such, we can expect that many more gravity wave detections will be possible in the coming years. This should come as no surprise, seeing as how LIGO has made two additional detections since the winter of 2016.

With many more expected to come, astronomers will have many opportunities to study black holes mergers, not to mention the physics that drive them!

Further Reading: UCI, MNRAS