Study: Neptune's Disappearing Clouds Linked to Solar Cycle

2023-08-28

00:00 / 00:00
复读宝 RABC v8.0beta 复读机按钮使用说明
播放/暂停
停止
播放时:倒退3秒/复读时:回退AB段
播放时:快进3秒/复读时:前进AB段
拖动:改变速度/点击:恢复正常速度1.0
拖动改变复读暂停时间
点击:复读最近5秒/拖动:改变复读次数
设置A点
设置B点
取消复读并清除AB点
播放一行
停止播放
后退一行
前进一行
复读一行
复读多行
变速复读一行
变速复读多行
LRC
TXT
大字
小字
滚动
全页
1
  • Scientists say they have discovered new evidence that cloud activity on Neptune is linked to atmospheric changes on the planet caused by the sun.
  • 2
  • Researchers say the evidence is based on observations collected by several telescopes over a period of nearly 30 years.
  • 3
  • Data was collected by the Hubble Space Telescope - operated by the American space agency NASA - as well as the W.M. Keck Observatory in Hawaii and the Lick Observatory in California.
  • 4
  • Astronomers recorded atmospheric changes on Neptune as they examined the cloud data.
  • 5
  • The researchers found that the changes followed the sun's natural cycle.
  • 6
  • Each natural cycle, known as the solar cycle, lasts about 11 years.
  • 7
  • During this cycle, the sun's magnetic field completely flips.
  • 8
  • This means the sun's north and south magnetic poles change places.
  • 9
  • They then flip back after another 11 years.
  • 10
  • Before the flip, a major increase in solar activity happens.
  • 11
  • This can send powerful collections of solar particles shooting through space.
  • 12
  • The scientists who examined the telescope data said they found that Neptune appeared brightest in 2002, then dimmed in 2007.
  • 13
  • The planet became bright again in 2015, but then darkened in 2020 to the dimmest level ever observed.
  • 14
  • The team said the observations also showed Neptune lost nearly all of its clouds beginning in 2019.
  • 15
  • Astronomers at the University of California, Berkeley (UC Berkeley) led the research.
  • 16
  • They recently reported their findings in a study in the publication Icarus.
  • 17
  • Imke de Pater is a retired professor of astronomy at UC Berkeley and was the lead writer of the study.
  • 18
  • She said in a statement she was surprised by how quickly clouds disappeared on Neptune.
  • 19
  • She noted cloud activity had dropped sharply "within a few months."
  • 20
  • "Even four years later, the images we took this past June showed the clouds haven't returned to their former levels," said Erandi Chavez.
  • 21
  • She is a student at Harvard University's Center for Astrophysics who took part in the study while at UC Berkeley.
  • 22
  • "This is extremely exciting and unexpected," Chavez said.
  • 23
  • She noted the finding was unusual "since Neptune's previous period of low cloud activity was not nearly as dramatic and prolonged."
  • 24
  • Neptune, about four times wider than Earth, is the eighth and most distant major planet orbiting our sun, NASA says.
  • 25
  • It receives sunlight with only about 0.1 percent intensity of our planet.
  • 26
  • For this reason, the researchers found it surprising that Neptune would be heavily influenced by solar activity.
  • 27
  • The planet also receives intense winds that can blow around clouds.
  • 28
  • The scientists looked at images captured by the different telescopes.
  • 29
  • They discovered clear patterns between seasonal changes in Neptune's cloud cover and the solar cycle.
  • 30
  • The team found that during periods when the sun gave off more intense ultraviolet (UV) light, more clouds appeared on the planet two years later.
  • 31
  • De Pater said the newly discovered data provides "the strongest evidence yet that Neptune's cloud cover correlates with the sun's cycle."
  • 32
  • He added the findings "support the theory that the sun's UV rays, when strong enough, may be triggering a photochemical reaction that produces Neptune's clouds."
  • 33
  • Photochemical is a term relating to how chemicals are affected by light.
  • 34
  • The researchers are continuing to follow cloud activity on Neptune.
  • 35
  • They noted that the latest images taken of the planet, in June 2023, showed clouds started to return.
  • 36
  • The team says this finding further strengthens their evidence.
  • 37
  • This is because the scientists see a link between the increasing cloud cover and the release of intense UV light over the past two years.
  • 38
  • The researchers say further study is needed to confirm their latest results.
  • 39
  • They say the research will be important not only for learning more about Neptune, but can also help scientists gain a better understanding of how similar planets outside our solar system behave.
  • 40
  • I'm Bryan Lynn.