This week, spacefans, we have have black holes, an update on the James Webb Space Telescope, and what have those ingenious Indians done now!
INDIA JOINS THE SPACEPLANE CLUB
After amazing the world by getting a probe to Mars for, in space agency terms, next to nothing, and what’s more, doing it straight off the bat first time, has to be admired, as was the sight of the control room filled with so many overjoyed, sari-clad, female scientists! Our workhorse satellite launcher, the PSLV rocket, has an excellent success rate. That India can provide the world with the most affordable satellite launch capability has allowed the nation to carve a niche for itself and I’m sure Elon musk will be taking careful notes. It should not be wonder that a lot of countries go to them for their satellite launch needs.
Credit:Getty Images
They are not planning on sitting on their laurels. India has sucessfully sent up a reusable spaceplane that looks unsurprisingly familiar – mechanics are mechanics after all. This first experiment was on the small side, but plans are afoot to build a version that is six times bigger, and which can carry 10 tons of payload, as well as possible manned missions. I wish them the best.
JAMES WEBB SPACE TELESCOPE INSTRUMENTS SUCESSFULLY INSTALLED
The team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland have been very busy installing the science package into the telescope.
“Our personnel were navigating a very tight space with very valuable hardware,” said Jamie Dunn, ISIM Manager (ISIM stands for ‘Integrated Science Instrument Module’). “We needed the room to be quiet so if someone said something we would be able to hear them. You listen not only for what other people say, but to hear if something doesn’t sound right.”
Time lapse video of two dozen engineers and technicians successfully installing the package of science instruments of the James Webb Space Telescope into the telescope structure.
Credits: NASA’s Goddard Space Flight Center/Michael McClare, Nasreen Alkhateeb
Before the procedure, the engineers and technicians had trained with test runs, computer modeling and a mock-up of the instrument package. This is a critical mission operation so they had to ensure they got it right first time.
“This is a tremendous accomplishment for our worldwide team,” said John Mather, James Webb Space Telescope Project Scientist and Nobel Laureate. “There are vital instruments in this package from Europe and Canada as well as the US and we are so proud that everything is working so beautifully, 20 years after we started designing our observatory.”
More tests need to be performed to ensure the telescope and its instruments will be able to safely withstand the stresses of launch now that everything is in place.
“Designing and building something of this magnitude and complexity, with this amount of new technology, is far from routine,” said Dunn. “While every project has their share of ups and downs, the JWST team has had to work through a lot over the life of this project. The character and dedication of this team is extraordinary, they’ve always recovered brilliantly, and they’ve made many personal sacrifices to get us to this point.”
I for one will be holding my breath and praying to the nearest deity that it gets safely off the ground!
OF BLACK HOLES AND DARK MATTER
Dark matter is a mysterious substance comparing most of the material universe, currently widely thought to be some form of massive exotic particle. However, another, intriguing view is that dark matter is in fact made of black holes which formed during the first second of our universe’s existence, known as primordial black holes. Now a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, suggests that this interpretation works well with our current knowledge of cosmic infrared and X-ray background glows and may explain the unexpectedly high masses of merging black holes detected last year.
“This study is an effort to bring together a broad set of ideas and observations to test how well they fit, and the fit is surprisingly good,” said Alexander Kashlinsky, an astrophysicist at NASA Goddard. “If this is correct, then all galaxies, including our own, are embedded within a vast sphere of black holes each about 30 times the sun’s mass.”
Back in 2005, Kashlinky and a team of astronomers explored the cosmic infrared background (CIB) using the Spitzer Space Telescope which observes the Universe via the near-infrared, as this can see through all those inconvenient dust clouds that get in the way. This study showed unexpected patchiness. The CIB glow is more irregular than can be explained by distant unresolved galaxies, and this excess structure is thought to be light emitted when the universe was less than a billion years old. Scientists think it likely originated from the first luminous objects to form in the universe, which includes both the first stars and black holes. These early stars emitted mainly optical and ultraviolet light, which due to the Doppler effect, was stretched in to the red end of the spectrum. The puzzling thing is though, that the same patchiness is found in the cosmic x-ray background (CXV), so the only thing we know of that can be luminous over such a wide range is a black hole.
There are many ideas as to the nature of dark matter, including new types of particle, but nothing so far has ticked all the boxes for solving one of the most headscratching issues in astrophysics.
“These studies are providing increasingly sensitive results, slowly shrinking the box of parameters where dark matter particles can hide,” Kashlinsky said. “The failure to find them has led to renewed interest in studying how well primordial black holes — black holes formed in the universe’s first fraction of a second — could work as dark matter.”
Last September, the first detection of gravitational waves, plus the first direct detection of black holes was captured by the Laser Interferometer Gravitational-Wave Observatory (LIGO) facilities in Hanford, Washington, and Livingston, Louisiana.
“Depending on the mechanism at work, primordial black holes could have properties very similar to what LIGO detected,” Kashlinsky explained. “If we assume this is the case, that LIGO caught a merger of black holes formed in the early universe, we can look at the consequences this has on our understanding of how the cosmos ultimately evolved.”
Primordial black holes, if they exist, could be similar to the merging black holes detected by the LIGO team in 2015. This computer simulation shows in slow motion what this merger would have looked like up close. The ring around the black holes, called an Einstein ring, arises from all the stars in a small region directly behind the holes whose light is distorted by gravitational lensing. The gravitational waves detected by LIGO are not shown in this video, although their effects can be seen in the Einstein ring. Gravitational waves traveling out behind the black holes disturb stellar images comprising the Einstein ring, causing them to slosh around in the ring even long after the merger is complete. Gravitational waves traveling in other directions cause weaker, shorter-lived sloshing everywhere outside the Einstein ring. If played back in real time, the movie would last about a third of a second.
Credits: SXS Lensing
In his new paper, published May 24 in The Astrophysical Journal Letters, Kashlinsky analyzes what might have happened if dark matter consisted of a population of black holes similar to those detected by LIGO. The black holes distort the distribution of mass in the early universe, adding a small fluctuation that has consequences hundreds of millions of years later, when the first stars begin to form.
For much of the universe’s first 500 million years, normal matter remained too hot to coalesce into the first stars. Dark matter was unaffected by the high temperature because, whatever its nature, it primarily interacts through gravity. Aggregating by mutual attraction, dark matter first collapsed into clumps called mini haloes, which provided a gravitational seed enabling normal matter to accumulate. Hot gas collapsed toward the mini haloes, resulting in pockets of gas dense enough to further collapse on their own into the first stars. Kashlinsky shows that if black holes play the part of dark matter, this process occurs more rapidly and easily produces the lumpiness of the CIB detected in Spitzer data even if only a small fraction of mini haloes manage to produce stars.
As cosmic gas fell into the mini haloes, their constituent black holes would naturally capture some of it too. Matter falling toward a black hole heats up and ultimately produces X-rays. Together, infrared light from the first stars and X-rays from gas falling into dark matter black holes can account for the observed agreement between the patchiness of the CIB and the CXB.
Occasionally, some primordial black holes will pass close enough to be gravitationally captured into binary systems. The black holes in each of these binaries will, over eons, emit gravitational radiation, lose orbital energy and spiral inward, ultimately merging into a larger black hole like the event LIGO observed.
“Future LIGO observing runs will tell us much more about the universe’s population of black holes, and it won’t be long before we’ll know if the scenario I outline is either supported or ruled out,” Kashlinsky said.
Kashlinsky leads science team centered at Goddard that is participating in the European Space Agency’s Euclid mission, which is currently scheduled to launch in 2020. The project, named LIBRAE, will enable the observatory to probe source populations in the CIB with high precision and determine what portion was produced by black holes.
LISA PATHFINDER ON ITS WAY TO FIND GRAVITATIONAL WAVES IN SPACE
As we know, gravitation waves were first detected last year by the by the ground-based Laser Interferometer Gravitational-Wave Observatory (LIGO). The ESA’s LISA Pathfinder mission is a space-based observatory that will have the sensitivity to pick up exotic signals impossible to pick up from the ground. The idea is to gently fly around two identical gold-platinum cube test masses which are dense and insensitive to magnetic fields. Scientists have now stated that they have more than exceeded the mission requirements.
“The measurements have exceeded our most optimistic expectations,” said Paul McNamara, the LISA Pathfinder project scientist at ESA’s Directorate of Science, Noordwijk, the Netherlands. “We reached the level of precision originally required for LISA Pathfinder within the first day, and so we spent the following weeks improving the results a factor of five better.”
“LISA Pathfinder was always intended as a stepping stone to the level of performance needed for a full-scale gravitational wave observatory, but these results tell us we’ve nearly made the full jump. A full-scale observatory with LISA Pathfinder’s performance would achieve essentially all of the ultimate science goals,” said Ira Thorpe, a team member at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “That’s amazing in itself, and data from this mission will help us build on an already impressive foundation.”
The LISA Pathfinder mission is an ESA-led effort to demonstrate technologies for a future gravitational wave observatory in space. NASA Goddard astrophysicist Ira Thorpe, a member of the team, discusses the mission and its spectacular results so far.
Credits: NASA’s Goddard Space Flight Center
Essentially, the space craft is moving in formation with the test masses in order to keep them in a drag-free environment. The point of this is to isolate them from outside influences. Even cosmic rays can influence them by transferring electric charge, so the scientists are testing out a way of removing this using ultraviolet light.
“These impressive results show that LISA Pathfinder has successfully demonstrated some of the advanced technologies needed for a future space-based gravitational wave observatory,” said Paul Hertz, director of NASA’s Astrophysics Division in Washington. “ESA is currently planning such a mission for the 2030s, and NASA is working closely with ESA in exploring how we might continue the successful LISA Pathfinder partnership in that mission.”
That’s it till next time spacefans, in the meantime, fly dangerous!
This article originally appeared on TheMittani.com, written by Feiryred.
