Space exploration is the exploration and discovery of outer space by use of space technology and is conducted by both robotic spacecraft and humans. Astronomy, which is the viewing of objects in space from Earth, is thought to predate recorded history, but it was the inspiration to modern space exploration. Humans explore space for many reasons including the survival of humankind if Earth cannot sustain life, uniting nations, and scientific research.
Physical space exploration began in Germany, where scientists developed and tested a V-2 rocket during World War II. This rocket became the first man-made object to enter space, alongside the launch of the A-4 in October of 1942. After the war ended, the United States used rockets captured from the Germans and their scientists to research and study rockets for military and civilian purposes. Although the Germans launched the first man-made object into space, the first exploration of space occurred in May of 1946, when the United States launched a V-2 for an experiment to analyze cosmic radiation.
In 1947, fruit flies became the first animals in space and the first pictures of Earth were taken. Both of these experiments were conducted using American V-2s. The Soviets also launched animal and radiation experiments in 1947, with the help of German scientists. These experiments were conducted using a variant of the V-2 known as the R-1. All of these early space exploration experiments were limited to short flights in sub-orbital space.
The Soviets conducted the first successful orbital mission in October of 1957 after launching the unmanned space vehicle Sputnik 1. This satellite weighed around 184 pounds and transmitted beeps down to radios across the earth, which scientists analyzed to measure the electron density in the ionosphere. The beeps also contained encoded information about the temperature and pressure of Sputnik, which helped researchers know its safety status. Sputnik eventually burned up upon re-entering the atmosphere, but its launch and success paved the way for other missions, including the successful launch of Explorer 1 by America in 1958. The first human flight was launched by Russia in 1961, successfully sending cosmonaut Yuri Gagarin into space for one Earth orbit aboard Vostok 1. America launched Mercury-Redstone 3 about a month later with Alan Shepard on board, but this flight was suborbital.
The next step in space exploration was successfully landing an object on a planetary body. This was accomplished in 1959 when Russia’s Luna 2 landed on the moon. America’s Apollo 11 was the first manned spacecraft to reach the moon. Venera 7 was the first spacecraft to land on another planet, landing in 1970, but this mission lasted less than thirty minutes. Important figures in space exploration include Kerim Kerimov, who was one of the leaders in the Vostok 1 mission, and Christopher C. Kraft, Jr., who was NASA’s first flight director.
Through the 1970s NASA ramped up its space exploration with the launches of several space orbiters, including one would much later make history. NASA launched Voyager 1 on September 5, 1977, an orbiter that was expected to last several years, exploring the outer planets. It visited Jupiter in 1979 and Saturn in 1980. The spacecraft’s primary mission ended on November 20, 1980, however, Voyager 1 is still going strong today, 36 years later.
Space Exploration got a huge lift when NASA launched the first Space Shuttle mission on April 12, 1981. That launch touched off a 30-year manned space program that saw 135 crewed missions into space. In 2000, the International Space Station paved a way for a continuing human presence in space. The Space Shuttle then became utilized as a vehicle to transport humans to and from the orbiting lab. After 11 years of supplying humans and cargo to the ISS, the Shuttle program was retired, leaving Russia as the only space agency capable of launching humans to and from the ISS — aboard its Soyuz spacecraft.
During the 2000s, many plans were announced for space exploration, including China’s plan to build and launch a 60-ton multi-module space station by 2020. NASA announced in the NASA Authorization Act of 2010 that it would build the Space Launch System (SLS), which would carry important equipment for experiments, the Orion Multi-Purpose Crew Vehicle, and other needed cargo. This station would also provide international and commercial transportation services to the International Space Station.
The focus of space exploration has shifted to using automated vehicles because these make missions less expensive to operate and allows researchers to gather information from areas where humans cannot reach. Optimal automated vehicles should be able to operate if something fails, should be able to attain a goal with a given set of actions, and should be able to sense its environment and make choices based on its findings. These types of vehicles would provide space programs throughout the world the ability to explore deep space with great efficiency.
After the retiring of the Space Shuttle program in 2011, NASA began looking for large corporations to fund the future of space travel. Several companies had already been working on space vehicles and were looking to secure contracts with NASA and other agencies to launch vehicles into space.
SpaceX was the first company to move in this direction when it successfully launched its Dragon capsule in 2012 and successfully docked with the ISS. Orbital Sciences has also shown commercial success after launching its Cygnus resupply ship to the orbiting lab in 2013.
Among the most historic feats accomplished in the space exploration field is the deep space exploration that has occurred with NASA’s Voyager 1, which has traveled more than 11 billion miles since its launch in 1977. NASA reported in September 2013 that the orbiter has made history when it left the heliopause, moving out of the Solar System and into interstellar space.
While astronomers have located more than 1,000 verified exoplanets and several thousand other potential candidates, they have yet to find a confirmed exomoon, but now, a new study posted to thearXiv prepublication server could provide evidence of the first such discovery.
According to Engadgetand BBC News, Dr. David Kipping, an assistant professor of astronomy at Columbia University, and his colleagues used data from the Kepler Space Telescope to detect signs of what appears to be a Neptune-sized moon located about 4,000 light years from Earth.
Said exomoon was found orbiting a planet about the same size and approximately 10 times more massive than Jupiter in the Kepler-1625 system, and the authors detected its existence when they noticed a decrease in brightness before and/or after the planet passed in front of its host star.
The Kepler Space Telescope, BBC News explained, hunts for planets by looking for changes in brightness that occur when a planet passes in front of its star. In this study, Dr. Kipping’s group looked for dips in starlight that happened before and/or after the planet passed in front of its sun. Such a signal was detected during three of the planet’s transits, the researchers reported.
Ideally, the researchers told the UK news outlet that they would have liked to have detected more signals, as that would have increased the level of confidence that they had indeed located the first ever verified exomoon. “We would merely describe it at this point as something consistent with a moon,” Dr. Kipping said. “But, who knows, it could be something else.”
Follow-up observations needed to confirm the discovery
The researchers plan to further investigate the potential moon with the Hubble Space Telescope in October, and while the object is – in Engadget’s words – “one of the strongest candidates for an exomoon to date,” those follow-up observations will confirm or dismiss the discovery.
Dr. Kipping and his co-authors have assigned a confidence level of four sigma to their signal, which according to BBC News describes how unlikely that it is that an experimental result is due to pure luck. In this case, it’s like flipping a coin and getting 15 straight heads, they explained.
However, the researcher said that this was not the ideal way to evaluate the potential detection. He said that he and his colleagues were “excited about it… statistically, formally, it’s a very high probability. But do we really trust the statistics? That’s something unquantifiable. Until we get the measurements from Hubble, it may as well be 50-50 in my mind.”
So while there is a fairly good chance that this is indeed an exomoon, the researchers are unable to completely rule out that the object is something else completely – at least, not until manage to take a second look at it with Hubble later on this year. Hubble, Phys.org explained, is capable of collecting better data than Kepler, and if the discovery is confirmed, it would make this not only the first ever confirmed exomoon, but also the largest moon ever observed, they noted.
“I’d say it’s the best [candidate] we’ve had. Almost every time we hit a candidate, and it passes our tests, we invent more tests until it finally dies – until it fails one of the tests,” Dr. Kipping told BBC News. “In this case, we’ve applied everything we’ve ever done and it’s passed all of those tests.”
A pair of solar flares, including the most powerful one in more than a decade, were detected by NASA’s Solar Dynamics Observatory sun-monitoring probe early Wednesday morning, experts at the US space agency confirmed in an announcement released later on in the day.
The first of the two flares was classified as an X2.2 flare and peaked at 5:10 am EDT, while the second was a larger X9.3 flare that peaked at 8:02 am EDT, NASA reported. X-class flares, they noted, are the most intense, while the number reveals more information about their strength.
“An X2 is twice as intense as an X1, an X3 is three times as intense, etc,” the agency explained. The X9.3 flare was the strongest observed since an X9.0 in December 2006 and the eighth most powerful since at least June 1996, according to Smithsonian.com and SpaceWeatherLive.com.
Both of the flares erupted from AR 2673, an active region on the sun which was also responsible for producing a mid-level solar flare on Monday, NASA said. They added that the X9.3 flare was the largest produced thus far during the current solar cycle, an 11 year period of the sun’s waxing and waning activity that began back in December 2008.
Sun Erupts With Monster X9 and X2 Flares - YouTube
Event caused radio blackouts, but should not affect hurricane monitoring
Space.com and the NOAA Space Weather Prediction Center (SWPC) reported that the second, more powerful of the flares resulted in high-frequency radio blackouts over a “wide area,” and that those blackouts caused “loss of contact for up to an hour” over the planet’s sunlit side. Low frequency communication, including that used for navigation, was also affected.
Unfortunately, the solar flares come at a bit of an inopportune time for those of us on Earth (and especially in the US), as many are relying on weather satellites to continue monitoring Hurricane Irma and other Atlantic-based storms. Fortunately, experts do not foresee any disruptions.
“The satellites are designed very specifically to take into account these kinds of events,” SWPC physicist Terry Onsager told LiveScience. While some older satellites could be hampered when hit with charged particles and strong magnetic fields from the sun, the probe which is providing images of Irma – GOES-16 – is new, having just been launched last November, he noted.
The size of the second flare is somewhat usual, according to Smithsonian.com, since the sun is currently at solar minimum, or the period of lowest activity during its 11-year cycle. However, as Onsager told LiveScience, this status is based more on the frequency of flares, not their potential intensity. “We can have large space weather events at any time during the solar cycle,” he said.
For the record, the largest flare ever recorded – at least, dating back to June 1996 – was an X28.0 that occurred on November 4, 2003, according to SpaceWeatherLive.com. It was one of only two flares known to have been categorized at least X20.0, with the other coming in April 2001.\
Astronomers believe that they have discovered an enormous new black hole thought to be nearly 100,000 more massive than the sun near the center of the Milky Way, and it may be the first ever actual detection of a long-hypothesized-but-never-proven type of space-time phenomena.
Writing in the journal Nature Astronomy, a team of researchers led by Tomoharu Oka of Japan’s Keio University explained that they were analyzing a cloud of molecular gas located close to the center of the galaxy when they noticed that the gases were exhibiting unusual behavior.
According to Time and Newsweek, those gases (which moved at different speeds and included molecules such as carbon monoxide and hydrogen cyanide) appeared to be moved by powerful gravitational forces. So, using computer-based simulations, they determined that the most likely cause would be a “gravitational kick” caused by an object similar to a black hole.
Specifically, they found that the molecules were being influenced by an “invisible compact object with a mass of about 105 solar masses,” which would be indicative of an intermediate-mass black hole (IMBH) – a hypothetical class of black hole in the 100 to 1 million solar mass range which would fall in between stellar black holes and their supermassive siblings.
If their discovery can be confirmed, it would be the first ever evidence of an IMBH, which have long been viewed as the “missing link” in the evolution of these massive objects. Their findings could help explain exactly how supermassive black holes actually form, The Guardian noted.
Additional research needed to verify the discovery
The smallest black holes, stellar black holes, form when certain types of stars explode at the end of their life cycles, but scientists are unsure how supermassive black holes form. One theory, The Guardian said, is that smaller black holes eventually merge together to form larger ones.
The problem with that theory is that while astronomers have discovered many, many stellar and supermassive black holes, they had never been able to locate even a lone intermediate-mass one. The newly-detected signal, Time said, may be coming from the core of a one-time dwarf galaxy that was consumed by the Milky Way. If so, that would seem to support the merger-based theory of supermassive black hole formation, but confirmation will require additional analysis.
“That growth should happen in part by mergers with other black holes and in part by accretion of material from the part of the galaxy that surrounds the black hole,” added Simmons, who was not involved in the new study. “Astrophysicists have been collecting observational evidence for both stellar mass black holes and supermassive black holes for decades, but even though we think the largest ones grow from the smallest ones, we’ve never really had clear evidence for a black hole with a mass in between those extremes.”
A longstanding theory describing what happens to matter before it is consumed by a black hole is wrong, according to new experiments conducted at the planet’s most powerful X-ray scanner and detailed in research published earlier this month in the journal Physical Review Letters.
Black holes are regions of spacetime that have gravitational fields so powerful that they prevent anything from escaping, including light and radiation. This, as Newsweekexplained, makes them rather difficult to study and forces scientists to rely on laboratory models to collect new data.
During one such experiment, researchers at Sandia National Laboratories in Albuquerque, New Mexico created a plasma similar to the charged gas found around black holes at the facility’s Z Machine when they made a startling discovery that contradicts a longstanding but never proven assumption about the X-rays that surround a black hole.
As lead author Guillaume Loisel explained in a statement, emissions from black holes cannot be directly observed. Instead, “we see emission from surrounding matter just before it is consumed by the black hole,” he said. “This surrounding matter is forced into the shape of a disk, called an accretion disk.”
These accretion disks radiates in the X-ray spectrum, and as NASAastrophysicist Tim Kallman told Newsweek, they contain a lot of information. “They can have many shapes,” and they have “bumps and wiggles in different parts of the spectra,” he explained. By interpreting those bumps and wiggles, researchers can determine how much gas the accretion disk contains, how hot it is, how many different elements it contains and more.
Findings may invalidate two decades worth of scientific studies
One theory that has stood the test of time, despite never being proven, is known as the Resonant Auger Destruction assumption. This assumption addresses the lack of photons coming from the accretion disk by assuming that a black hole’s powerful gravity and radiation prevents energized iron electrons from returning to lower energy states by emitting photons.
For the last five years, Loisel and his colleagues have used the Z Machine to put this assumption to the test, according to Newsweek. The powerful X-ray scanner allowed them to recreate energy surrounding the black hole and apply said energy to matter. Essentially, Kallman said, they came closer than ever to recreating the conditions found around an actual black hole.
The Sandia researchers applied the X-ray energies found around black holes to tiny silicon pieces to see if they could witness the Auger effect. Even though they precisely recreated the conditions and temperatures found around a black hole, however, they did not find any evidence of photons.
“If Resonant Auger Destruction is a factor, it should have happened in our experiment because we had the same conditions, the same column density, the same temperature. Our results show that if the photons aren’t there, the ions must be not there either,” Loisel told Newsweek. While he added that it is too soon to completely dismissing the Auger effect, he said that their findings “challenge models used to infer how fast black holes swallow matter from their companion star” and could invalidate “many scientific papers published over the last 20 years.”
For decades, astronomers have wondered if the sun’s core spins faster than its surface, and now, thanks to an international team of scientists, they have the answer: the interior makes a complete rotation in one week, which is 3.8 times faster than the middle and outermost layers.
What they did, the researchers explained in a statement, was study surface acoustic waves in the sun’s atmosphere. Some of those waves penetrate to the core and interact with gravity waves that have a “sloshing” motion similar to how water splashes around in a container that is half full.
By detecting these sloshing motions, they were able to measure the acoustic waves and figure out how long it took them to travel from the surface to the core and back again. By applying this new method to 16 years worth of GOLF data, the research team determined that the solar core rotated once per week. Their findings have been reported in the journal Astronomy & Astrophysics.
Data brings a decades-long search to a close
Experts have speculated for more than two decades that the sun’s interior may be spinning faster than the surface, but they had never been able to accurately measure its oscillations before, study co-author Roger Ulrich, a professor emeritus of astronomy at UCLA, said in a statement.
“The most likely explanation is that this core rotation is left over from the period when the sun formed, some 4.6 billion years ago,” Ulrich explained. “It’s a surprise, and exciting to think we might have uncovered a relic of what the sun was like when it first formed.”
The SOHO space observatory has been orbiting the sun for more than 20 years, using its GOLF instrument to conduct solar oscillation measurements once every 10 seconds. Thanks to this data, the authors of the new study were able to definitely conclude that earlier speculation was correct, and that the interior portion of the sun does indeed spin more quickly than the outer parts.
“We’ve been searching for these elusive g-waves [gravity waves] in our Sun for over 40 years, and although earlier attempts have hinted at detections, none were definitive. Finally, we have discovered how to unambiguously extract their signature,” lead author Eric Fossat from the Cote d’Azur Observatory explained in a statement released by the European Space Agency (ESA).
“It is really special to see into the core of our own Sun to get a first indirect measurement of its rotation speed,” he added. “But, even though this decades long search is over, a new window of solar physics now begins.”