All posts by Tom

The Tea Cup

The Galaxy Zoo project is really great, check it out and you can participate.

Chandra: Fancy a cup of cosmic tea? This one isn’t as calming as the ones on Earth. In a galaxy hosting a structure nicknamed the “Teacup,” a galactic storm is raging.

The source of the cosmic squall is a supermassive black hole buried at the center of the galaxy, officially known as SDSS 1430+1339. As matter in the central regions of the galaxy is pulled toward the black hole, it is energized by the strong gravity and magnetic fields near the black hole. The infalling material produces more radiation than all the stars in the host galaxy. This kind of actively growing black hole is known as a quasar.

Located about 1.1 billion light years from Earth, the Teacup’s host galaxy was originally discovered in visible light images by citizen scientists in 2007 as part of the Galaxy Zoo project, using data from the Sloan Digital Sky Survey. Since then, professional astronomers using space-based telescopes have gathered clues about the history of this galaxy with an eye toward forecasting how stormy it will be in the future. This new composite image contains X-ray data from Chandra (blue) along with an optical view from NASA’s Hubble Space Telescope (red and green).

The “handle” of the Teacup is a ring of optical and X-ray light surrounding a giant bubble. This handle-shaped feature, which is located about 30,000 light-years from the supermassive black hole, was likely formed by one or more eruptions powered by the black hole. Radio emission — shown in a separate composite image with the optical data — also outlines this bubble, and a bubble about the same size on the other side of the black hole.

Previously, optical telescope observations showed that atoms in the handle of the Teacup were ionized, that is, these particles became charged when some of their electrons were stripped off, presumably by the quasar’s strong radiation in the past. The amount of radiation required to ionize the atoms was compared with that inferred from optical observations of the quasar. This comparison suggested that the quasar’s radiation production had diminished by a factor of somewhere between 50 and 600 over the last 40,000 to 100,000 years. This inferred sharp decline led researchers to conclude that the quasar in the Teacup was fading or dying.

New data from Chandra and ESA’s XMM-Newton mission are giving astronomers an improved understanding of the history of this galactic storm. The X-ray spectra (that is, the amount of X-rays over a range of energies) show that the quasar is heavily obscured by gas. This implies that the quasar is producing much more ionizing radiation than indicated by the estimates based on the optical data alone, and that rumors of the quasar’s death may have been exaggerated. Instead the quasar has dimmed by only a factor of 25 or less over the past 100,000 years.

The Chandra data also show evidence for hotter gas within the bubble, which may imply that a wind of material is blowing away from the black hole. Such a wind, which was driven by radiation from the quasar, may have created the bubbles found in the Teacup.

Astronomers have previously observed bubbles of various sizes in elliptical galaxies, galaxy groups and galaxy clusters that were generated by narrow jets containing particles traveling near the speed of light, that shoot away from the supermassive black holes. The energy of the jets dominates the power output of these black holes, rather than radiation.

In these jet-driven systems, astronomers have found that the power required to generate the bubbles is proportional to their X-ray brightness. Surprisingly, the radiation-driven Teacup quasar follows this pattern. This suggests radiation-dominated quasar systems and their jet-dominated cousins can have similar effects on their galactic surroundings.

A study describing these results was published in the March 20, 2018 issue of The Astrophysical Journal Letters and is available online. The authors are George Lansbury from the University of Cambridge in Cambridge, UK; Miranda E. Jarvis from the Max-Planck Institut für Astrophysik in Garching, Germany; Chris M. Harrison from the European Southern Observatory in Garching, Germany; David M. Alexander from Durham University in Durham, UK; Agnese Del Moro from the Max-Planck-Institut für Extraterrestrische Physik in Garching, Germany; Alastair Edge from Durham University in Durham, UK; James R. Mullaney from The University of Sheffield in Sheffield, UK and Alasdair Thomson from the University of Manchester, Manchester, UK.

NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program for NASA’s Science Mission Directorate in Washington. The Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, controls Chandra’s science and flight operations.

Image Credit: NASA/CXC/Univ. of Cambridge/G. Lansbury et al; Optical: NASA/STScI/W. Keel et al.

Opportunity Signing Out

The last image from the Mars Exploration Rover Opportunity. The partial image marks the end of a remarkable mission unless there is some miracle.

The image is from the PanCam on the rover. Thanks to NASA and the rest (NASA/JPL-Caltech/Cornell/ASU ) for sharing.

NASA: Taken on June 10, 2018 (the 5,111th Martian day, or sol, of the mission) this “noisy”, incomplete image was the last data NASA’s Opportunity rover sent back from Perseverance Valley on Mars. The partial, full-frame image from the Panoramic Camera (Pancam) was sent up to NASA’s Mars Reconnaissance Orbiter around 9:45 a.m. PDT (12:45 p.m. EDT) to relay back to Earth as an intense dust storm darkened the skies around the solar-powered rover. The image was received on Earth at around 10:05 a.m. PDT (1:05 p.m. EDT).

Opportunity took this image with the left eye of the Pancam, with its solar filter pointed at the Sun. But since the dust storm blotted out the Sun, the image is dark. The white speckles are noise from the camera. All Pancam images have noise in them, but the darkness makes it more apparent. The transmission stopped before the full image was transmitted, leaving the bottom of the image incomplete, represented here as black pixels.

While this partial full-frame image was the last that Opportunity transmitted, it was not actually the last set of images from Opportunity. This image was taken at around 9:30 a.m. PDT (12:30 p.m. EDT) on June 10, 2018. Another set of images (PIA22930) was taken about three minutes later. The thumbnail versions of the last images taken were transmitted, but the rover lost contact before transmitting the full-frame versions.

NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Exploration Rover Project for NASA’s Science Mission Directorate in Washington.

For more information about Opportunity, visit https://www.nasa.gov/rovers and https://mars.nasa.gov/mer

Bennu Close Up

Here’s a close up of the asteroid Bennu. The image is from NASA’s OSIRIS-REx spacecraft (caption below). You will get a larger version by clicking the image above, however, I encourage you to go to the main image on the NASA page and click that one, it is huge and the detail is amazing. Keep in mind I try to keep the image file size reasonable so people with slower connections don’t have to wait too long and that image is a lot larger in terms of file size – but it’s really good.

NASA: This trio of images acquired by NASA’s OSIRIS-REx spacecraft shows a wide shot and two close-ups of a region in asteroid Bennu’s northern hemisphere. The wide-angle image (left), obtained by the spacecraft’s MapCam camera, shows a 590-foot (180-meter) wide area with many rocks, including some large boulders, and a “pond” of regolith that is mostly devoid of large rocks. The two closer images, obtained by the high-resolution PolyCam camera, show details of areas in the MapCam image, specifically a 50-foot (15 meter) boulder (top) and the regolith pond (bottom). The PolyCam frames are 101 feet (31 meters) across and the boulder depicted is approximately the same size as a humpback whale.

The images were taken on February 25 while the spacecraft was in orbit around Bennu, approximately 1.1 miles (1.8 km) from the asteroid’s surface. The observation plan for this day provided for one MapCam and two PolyCam images every 10 minutes, allowing for this combination of context and detail of Bennu’s surface.

Credit:  NASA/Goddard/University of Arizona

CHEOPS

CHEOPS or Characterising Exoplanet Satellite is steadily moving towards a launch date later this year. Currently the satellite is at Airbus Defence and Space Spain, Madrid and will eventually be shipped to Kourou, French Guiana for launch.

ExoMars Parachute in the Oven

This is one of those strange coincidences. Just a few days ago, Tuesday, I was having a conversation with a friend of mine about the precautions of bacteria from Earth going to other places other than home. “Well they do nothing because bacteria would die in outer-space.” NOT SO I countered. Bacteria can indeed live in “outer-space”, citing bacteria found on the outside of the International Space Station.

Today I saw this from ESA dealing with such issue on the ExoMars parachute and I knew I should have wagered on it (LOL).

ESA: A technician places a nearly 70 kg parachute designed for ESA and Roscosmos’s ExoMars 2020 mission inside the dry heater steriliser of the Agency’s Life, Physical Sciences and Life Support Laboratory, based in its Netherlands technical centre.

Mars is a potential abode of past and perhaps even present-day life. Accordingly, international planetary protection regulations require any mission sent to the Red Planet to undergo rigorous sterilisation, to prevent terrestrial microbes from piggybacking their way there.

The Lab’s Alan Dowson explains: “This is the ‘qualification model’ of the 35-m diameter main parachute for ExoMars 2020, basically a test version which allows us to finalise our sterilisation procedures ahead of the flight model chute’s arrival.

“This version has been threaded with thermal sensors, allowing us to see how long it takes to reach the required sterilisation temperature in all parts of the folded parachute, even in the hardest to heat points. Our target was to sterilise at 125 °C for 35 hours and 26 minutes, and the oven took about 44 hours to reach that temperature to begin with.”

The oven is part of the Lab’s 35 sq. m ‘ISO Class 1’ cleanroom, one of the cleanest places in Europe. All the cleanroom’s air passes through a two-stage filter system. Anyone entering the chamber has to gown up in a much more rigorous way than a hospital surgeon, before passing through an air shower to remove any remaining contaminants.

“If you imagine our clean room as being as big as the entire Earth’s atmosphere, then its allowable contamination would be equal to a single hot air balloon,” adds Alan. “Our ISO 1 rating means we have less than 10 dust particles measuring a tenth of one millionth of a metre in diameter per cubic metre of air.”

The mostly nylon and Kevlar parachute, packed into an 80-cm diameter donut-shaped unit, was delivered by Italy’s Arescosmo company. This qualification model will now be sent back there for testing, to ensure this sterilisation process causes no change to the parachute’s material properties.

Alan explains: “We will receive the parachute flight model later this spring for the same sterilisation process – identical to this version, except without any thermal sensors.”

ExoMars’s smaller first stage 15-m diameter parachute has already gone through sterilisation using the oven. This is the parachute that opens during initial, supersonic atmospheric entry, with the second, larger chute opening once the mission has been slowed to subsonic velocity.

The Lab has also tackled a variety of ExoMars instruments and subsystems, but this second stage subsonic parachute is the single largest item to be sterilised. The sterilisation process aims to reduce the overall mission ‘bioburden’ to a 10 thousandth of its original level.

Image: ESA–M. Cowan

Happy Pi Day!

HAPPY Pi Day!!

Have a look at a Pi Day website. I bet you will want to spend some time there, it’s a fun site.

Stop back later for coverage of the Soyuz MS 12 launch to the International Space Station. Aboard the Soyuz is NASA astronauts Nick Hague and Christina Koch, and cosmonaut Alexey Ovchinin of Roscosmos.

NASA TV coverage starts at 18:00 UT / 14:00 ET with launch time scheduled for 19:14 UT / 15:14 ET.

Image.

Continuing Science

In a great example of studying data we already have NASA has selected teams to study actual physical evidence, moon rocks, from the Apollo missions. Thanks to judicious use of these samples to-date there is enough to use and hopefully more for the future when technology and methods continue to improve in order to gain the most we can. Someday we might replenish our stocks.

The image above is Harrison Schmitt collecting samples at Station 1 during the last of the Apollo mission to the moon. Schmitt as the pilot of the Lunar Module, part of a crew which included Commander Eugene Cernan and Command Module Pilot Ronald Evans. Image credit: NASA/Eugene A. Cernan.

Here’s the story from NASA: NASA has selected nine teams to continue the science legacy of the Apollo missions by studying pieces of the Moon that have been carefully stored and untouched for nearly 50 years. A total of $8 million has been awarded to the teams.

“By studying these precious lunar samples for the first time, a new generation of scientists will help advance our understanding of our lunar neighbor and prepare for the next era of exploration of the Moon and beyond, “ said Thomas Zurbuchen, Associate Administrator for NASA’s Science Mission Directorate in Washington, DC. “This exploration will bring with it new and unique samples into the best labs right here on Earth.”

Six of the nine teams will look at one of the three remaining lunar samples, from Apollo missions 15, 16, and 17, which have never been exposed to Earth’s atmosphere. The particular sample these teams will study came to Earth vacuum-sealed on the Moon by the Apollo 17 astronauts Harrison Schmitt and Gene Cernan in 1972. 

The Apollo 17 sample comprises about 800 grams (1.8 pounds) of material, still encased in a “drive tube” that was pounded into the lunar regolith to collect a core of material. That core preserves not just the rocks themselves but also the stratigraphy from below the surface so today’s scientists can, in a laboratory, study the rock layers exactly as they existed on the Moon. The core has been carefully stored at NASA’s Johnson Space Center in Houston, Texas, since December 1972. 

Other teams will be studying samples that have also been specially curated, some from Apollo 17 that were brought to Earth and then kept frozen, and samples from the Apollo 15 mission which have been stored in helium since 1971.

NASA has only collected samples from a few places on the Moon so far, but NASA knows from the remote sensing data that the Moon is a complex geologic body. From orbit, the agency has identified types of rocks and minerals that are not present in the Apollo sample collection.  

“Returned samples are an investment in the future. These samples were deliberately saved so we can take advantage of today’s more advanced and sophisticated technology to answer questions we didn’t know we needed to ask,” said Lori Glaze, acting director of NASA’s Planetary Science Division in Washington, DC. 

The nine institutions include:

NASA Ames Research Center/Bay Area Environmental Research Institute: A team led by Alexander Sehlke will complete an experiment started 50 years ago by studying the frozen lunar samples from Apollo 17 to see how volatiles like water are stored in the radiation environment of the lunar surface, which is not protected by an atmosphere like Earth. 

NASA Ames – A team led by David Blake and Richard Walrothwill study the vacuum-sealed sample to study “space weathering” or how exposure to the space environment affects the Moon’s surface. 

NASA’s Goddard Spaceflight Center: A team led by Jamie Elsila Cook will study the vacuumed-sealed sample to better understand how small organic molecules—namely, precursors to amino acids—are preserved on the Moon. 

NASA Goddard: A team led by Barbara Cohen and Natalie Curran will study the vacuum-sealed sample to investigate the geologic history of the Apollo 17 site. They’ll specifically be looking at the abundance of noble gases in the sample, which can tell them about the sample’s age. 

University of Arizona:A team led by Jessica Barnes will study how curation affects the amount of hydrogen-bearing minerals in lunar soil, which will help us better understand how water is locked in minerals on the Moon. 

University of California Berkeley: A team led by Kees Welten will study how micrometeorite and meteorite impacts may have affected the geology of the lunar surface.

US Naval Research Laboratory. A team led by Katherine Burgess will look at the frozen samples and the samples stored in helium to study how airless bodies are affected by exposure to the space environment. 

University of New Mexico: A team led by Chip Shearer will look at the vacuum-sealed sample to study the geologic history of the Apollo 17 site. They will be studying samples from a region that had been cold enough for water to freeze—called a “cold trap.” This will be the first time a sample from one of these cold traps will be examined in the lab.

Mount Holyoke College/Planetary Science Institute: A team led by Darby Dyar will look at both the vacuum-sealed samples and samples stored on helium to study volcanic activity on the Moon. They’ll specifically look at tiny glass beads that formed rapidly during an ancient lunar eruption.

The samples won’t be opened right away. First, the teams will work together and with the curation staff at NASA Johnson to determine the best way to open the sample to avoid contaminating them and maximize the science to be gained.

The teams for the Apollo Next-Generation Sample Analysis grants were selected by the Planetary Science Division and will be funded by the Lunar Discovery and Exploration Program. 

Merging Galaxies

Can you image being on a planet in either one of these colliding galaxies? One day in the very far future this might be a good analogy of our merging with the Andromeda galaxy. What would the sky look like, even in the daytime?

ESA: Located in the constellation of Hercules, about 230 million light-years away, NGC 6052 is a pair of colliding galaxies. They were first discovered in 1784 by William Herschel and were originally classified as a single irregular galaxy because of their odd shape. However, we now know that NGC 6052 actually consists of two galaxies that are in the process of colliding. This particular image of NGC 6052 was taken using the Wide Field Camera 3 on the NASA/ESA Hubble Space Telescope.

A long time ago gravity drew the two galaxies together into the chaotic state we now observe. Stars from within both of the original galaxies now follow new trajectories caused by the new gravitational effects. However, actual collisions between stars themselves are very rare as stars are very small relative to the distances between them (most of a galaxy is empty space). Eventually things will settle down and one day the two galaxies will have fully merged to form a single, stable galaxy.

Our own galaxy, the Milky Way, will undergo a similar collision in the future with our nearest galactic neighbour, the Andromeda Galaxy. Although this is not expected to happen for around 4 billion years so there is nothing to worry about just yet.

This object was previously observed by Hubble with its old WFPC2 camera. That image was released in 2015.

Image: ESA/Hubble & NASA, A. Adamo et al.; CC BY 4.0