2, the Milky Way black belt seen on Earth is the gas dust left over from the formation of the Milky Way. When the Milky Way formed, large tracts of matter were attracted by the giant black hole or black hole in the center, and rotated around them, forming the Milky Way's four spiral arms, and the area between the arms is distributedMore sparse, but these areas are not completely empty, leaving very thin gas, because the units across a wide range, so still can block some of the light. 3. The discovery surprised experts: there is a huge black hole at the center of the Milky Way, and the prevailing theory was that nothing could exist near a black hole. These stars were discovered thanks to the Chandra X-ray space telescope in the United States. They are only 9.5 billion kilometers (less than 1 light year) from the central region of the Milky Way. To be added, the distance from Earth to the black hole at the center of the Milky WayIt's about 60,000 light years. 4. After a star explosion in the Milky Way, if cosmic rays, including gamma rays, reach the Earth, they can cause a sharp drop in temperature and lead to an ice age. Knowledge introduction: The meaning of black hole; Black hole, a special kind of object predicted by general relativity. Its basic feature is that it has a closed horizon. The event horizon is the boundary of the black hole. Foreign matter and radiation can enter the event horizon, and any matter inside the aircraft horizon can not run outside.
5. Black holes were first calculated by the German mathematician Karl Schwarzschild, and anything around a black hole is eitherSignal, light or matter can not escape, space-time here becomes a bottomless hole, such a can not see the touch can not detect the place is called a black hole.
Not in theory. The stewardess will ask everyone to put everything away before take-off. In fact, it is OK, one is that the camera has no radiation, there is no problem, and the second is that the stewardess is in his seat when taking off and landing, and it does not care about you. The reason why it is not allowed to use is that you are afraid of unexpected severe bumps and shocks during takeoff and landing, and then you do not grasp the camera, and your hand may slip the camera, mobile phone or something may call into your face, or hit itOther passengers suffered head injuries.
You want to make sure your digital camera doesn't emit wireless signals. Some new cameras may have features such as Bluetooth or other wireless networking capabilities that can interfere with the aircraft's sophisticated electronics and affect flight safety. If so, for your own safety and the safety of others, do not open it. Taking pictures of cabin crew members, especially stewardesses, will be stopped. Of course, we should consciously respect other people's portraits and privacy.
Yes. At present, domestic airlines are required to turn off all electronic devices, digital cameras and electronic devices during takeoff and landingA thunderstorm cloud is a billowing, fluctuating mass of water, ice crystals and air. When ice crystals in the cloud roll up and down in strong currents, water condenses into layers of ice on the surface of the ice crystals, forming hail. These ice crystals and water droplets, repeatedly torn and hit by strong air currents, are full of static electricity. Thunderstorm clouds often develop from cumulus clouds, which are the mature stage of convective cloud development.
3, generally speaking, the thunderstorm cloud refers to the cumulonimbus cloud, also known as the thunderstorm cloud, is a kind of accumulative cloud. Accumulative clouds are caused by adiabatic cooling of air in the form of convective movement, so that water vapor is saturated and condensed, including light cumulus cloud and concentrated cloudClouds, cumulonimbus, cumulus fragilis. Cumulonimbus cloud is thick and thick, the cloud body is huge like towering mountains, in the shape of steamed bread, which has updraft, making the shape like a flat top of the steamed bread.
3, the reason for the formation of typhoons is that the sea temperature is above 25℃; Certain positive vorticity initial disturbance; The shear of ambient wind in vertical direction is small. Low pressure or cloud disturbance at least a few latitudes from the equator. The initial stage of the typhoon is a tropical depression, from the initial low pressure circulation to the maximum average wind near the center of the eight, generally takes about 2 days, slow to three or four days, fast only a few hours.
4. Typhoon is a classification of tropical cyclones north of the equator and west of the dateline in the Asia-Pacific region. In meteorology, according to the worldThe World Meteorological Organization defines a tropical cyclone with a sustained wind speed of category 12 (64 knots or more, 37 meters per second or more, or 118 kilometers per hour or more) as a Hurricane or other terrestrial term. The closest word used in the Pacific Northwest is typhoon.