You are viewing the page for Feb. 18, 2006
  Select another date:
<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Science news and information about the Sun-Earth environment.


Solar Wind
speed: 370.8 km/s
5.6 protons/cm3
explanation | more data
Updated: Today at 2244 UT

X-ray Solar Flares

6-hr max:
A1 2135 UT Feb18
24-hr: A4 0840 UT Feb18
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 18 Feb '06

The sun is blank again. Solar activity should remain low. Credit: SOHO/MDI

Sunspot Number: 23
What is the sunspot number?
Updated: 17 Feb 2006

Far Side of the Sun

This holographic image reveals no sunspots on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 4.8 nT
0.4 nT north
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole should reach Earth on or about Feb. 20th. . Image credit: SOHO Extreme UV Telescope.


Solar Flares: Probabilities for a medium-sized (M-class) or a major (X-class) solar flare during the next 24/48 hours are tabulated below.
Updated at 2006 Feb 18 2204 UTC
FLARE 0-24 hr 24-48 hr
CLASS M 01 % 01 %
CLASS X 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 2006 Feb 18 2204 UTC
0-24 hr 24-48 hr
ACTIVE 20 % 15 %
MINOR 10 % 05 %
SEVERE 05 % 01 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 25 % 20 %
MINOR 10 % 10 %
SEVERE 05 % 05 %

What's Up in Space -- 18 Feb 2006
Subscribe to Space Weather News

The space station is visible in the night sky this month. Would you like to see it? Sign up for Spaceweather PHONE.

JUPITER & THE MOON: Tomorrow morning, Sunday, Feb. 19th, if you happen to be awake at the crack of dawn, look out the window. Jupiter and the Moon are having a pretty close encounter. The pair are so bright you can see them even after the sky turns morning blue: sky map.

NOVA! A few days ago, the star RS Ophiuchi exploded. Not the whole star, just some material dumped onto it by a neighboring red giant. The resulting nuclear conflagration is visible to the naked eye--barely--in the constellation Ophiuchus just before dawn: sky map. Astrophotographer John Chumack snapped this picture of RS Ophiuchi on Feb. 16th:

Normally RS Ophiuchi would be indistinguisable from the scatter of dim background stars in this image, but as a nova, it stands out front and center. The explosion multiplied RS Ophiuchi's brightness by a factor of 1700--from magnitude 12.5 to 4.5. "But, cautions Chumack, "the nova is fading now, currently at mag 5.3, so get out and take a look [before it disappears]."

DOUBLE RAINBOW: Whenever you see one rainbow, look for another, because rainbows always come in pairs. Witness this Feb. 2nd photo from Dan Bush of McFall, Missouri:

"I used a fisheye lens to capture the entire rainbow, which appeared very close to the photographer at one point," says Bush.

The bright inner rainbow is the primary bow, caused by sunbeams reflecting once inside falling raindrops. It's the bow you usually see. The less-bright outer rainbow is the secondary bow, caused by sunbeams reflecting twice inside raindrops. Secondary bows often go unnoticed, because they are usually very faint, but they are always there.

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 18 Feb 2006 there were 772 known Potentially
Hazardous Asteroids

Feb. 2006 Earth-asteroid encounters




2006 BM55

Feb. 5

8.4 LD


~110 m
2006 BX39

Feb. 10

8.2 LD


~225 m
Notes: LD is a "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 Web 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. See also Snow Crystals.

Solar and Heliospheric Observatory -- Realtime and archival images of the Sun from SOHO. (European Mirror Site)

Daily Sunspot Summaries -- from the NOAA Space Environment Center.

Current Solar Images --a gallery of up-to-date solar pictures from the National Solar Data Analysis Center at the Goddard Space Flight Center. See also the GOES-12 Solar X-ray Imager.

Recent Solar Events -- a nice summary of current solar conditions from

SOHO Farside Images of the Sun from SWAN and MDI.

The Latest SOHO Coronagraph Images -- from the Naval Research Lab

Daily images from the sun -- from the Big Bear Solar Observatory

List of Potentially Hazardous Asteroids -- from the Harvard Minor Planet Center.

Observable Comets -- from the Harvard Minor Planet Center.

What is the Interplanetary Magnetic Field? -- A lucid answer from the University of Michigan. See also the Anatomy of Earth's Magnetosphere.

Real-time Solar Wind Data -- from NASA's ACE spacecraft. How powerful are solar wind gusts? Read this story from Science@NASA.

More Real-time Solar Wind Data -- from the Solar and Heliospheric Observatory Proton Monitor.

Lists of Coronal Mass Ejections -- from 1998 to 2001

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1996, 1997, 1998, 1999; 2000; 2001; 2002; 2003; 2004; 2005; Jan-Mar 2006;

Space Audio Streams: (University of Florida) 20 MHz radio emissions from Jupiter: #1, #2, #3, #4; (NASA/Marshall) INSPIRE: #1; (Stan Nelson of Roswell, New Mexico) meteor radar: #1, #2;

Recent International Astronomical Union Circulars


This site is penned daily by Dr. Tony Phillips: email

You are visitor number 33760548 since January 2000.
©2019 All rights reserved.