You are viewing the page for May. 28, 2007
  Select another date:
<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Current conditions
Solar wind
speed: 434.0 km/sec
density: 0.8 protons/cm3
explanation | more data
Updated: Today at 2246 UT
X-ray Solar Flares
6-hr max: A0
1710 UT May28
24-hr: A3
1440 UT May28
explanation | more data
Updated: Today at: 2245 UT
Daily Sun: 27 May 07
The sun is blank today--no sunspots. Credit: SOHO/MDI
Sunspot number: 0
What is the sunspot number?
Updated 28 May 2007
Far side of the Sun:
This holographic image reveals no large spots on the farside of the sun. Image credit: SOHO/MDI
Planetary K-index
Now: Kp= 0 Quiet
24-hr max: Kp= 3
explanation | more data
Current Auroral Oval:
Europe, Antarctica, USA
Interplanetary Mag. Field
Btotal: 1.9 nT
Bz: 1.2 nT south
explanation | more data
Updated:Today at 2246 UT
Coronal Holes:
Earth is inside a solar wind stream flowing from the indicated coronal hole. Credit: SOHO Extreme Ultraviolet Telescope
NOAA Forecasts
Updated at: 2007 May 28 2203 UTC
0-24 hr
24-48 hr
01 %
01 %
01 %
01 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2007 May 28 2203 UTC
0-24 hr
24-48 hr
15 %
15 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
20 %
10 %
10 %
01 %
01 %
What's up in Space
May 28, 2007
He already has a neck tie. This year give Dad something truly heavenly for Father's Day: SpaceWeather PHONE.

STORM WARNINGS: Astronauts can breathe a little easier. A scientist using the Solar and Heliospheric Observatory (SOHO) has found a way to predict dangerous solar radiation storms. The new alert system offers as much as one hour advance warning, giving astronauts on EVA extra time to seek shelter and avoid radiation sickness. Get the full story from Science@NASA.

MARS IS COMING: Mars has been gone for a while, far from Earth on the other side of the sun. Good news: It's coming back. On May 26th, Mike Salway of Central Coast, Australia, took this picture through his 12-inch telescope:

"Mars is only 5.7 arcseconds wide, but many details are visible," says Salway. Especially prominent is the southern polar cap of Mars. Made of frozen CO2 or "dry ice," it reflects more sunlight than any other part of the planet. Summer is coming to the south of Mars, and this will cause the polar cap to shrink and fragment in the months ahead--a process worth watching.

Every night the view improves. Mars and Earth are converging for a close encounter in December 2007. By that time, Mars will have swollen three times wider and ten times brighter than it is now. Want a sneak preview? Wake up before dawn, as Salway did, and point your telescope at that red, first-magnitude "star" rising just ahead of the sun: sky map.

IRIDESCENCE: Yesterday in Brazil, at the Curitiba Botanical Garden, photographer Mendonca Jr glanced up from the statuary and beheld a colorful iridescent cloud:

Photo details: Sony H-5, 200mm, ISO 100, 1/1000 sec.

"The silhouette below the cloud is not a real person, but a statue called the Mother," he explains. She is located at the center of a fountain--hence the splashing water.

There is water in the cloud, too. Tiny water droplets diffract sunlight, giving rise to the cloud's soft pink and green colors. The key word is tiny. For diffraction to work properly, the cloud's droplets must be about 1000 times smaller than the ponderous drops we see splashing around the statue. Tiny droplets, big droplets. Altogether, "it was a lovely scene," he says.

Near-Earth Asteroids
Potentially Hazardous Asteroids (PHAs) are space rocks larger than approximately 100m that can come closer to Earth than 0.05 AU. None of the known PHAs is on a collision course with our planet, although astronomers are finding new ones all the time.
On May 28, 2007 there were 863 potentially hazardous asteroids.
May 2007 Earth-asteroid encounters:
Miss Distance
1862 Apollo
May 8
72 LD
2.4 km
2007 JD
May 11
12 LD
100 m
2007 JZ2
May 14
7.0 LD
30 m
Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.
Essential Links
NOAA Space Environment Center
  The official U.S. government bureau for real-time monitoring of solar and geophysical events, research in solar-terrestrial physics, and forecasting solar and geophysical disturbances.
Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  From the NOAA Space Environment Center
Current Solar Images
  from the National Solar Data Analysis Center
  more links...
©2007, -- This site is penned daily by Dr. Tony Phillips.
©2019 All rights reserved.