You are viewing the page for Apr. 19, 2007
  Select another date:
<<back forward>>
SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids

SpaceWeather.com
Science news and information about the Sun-Earth environment.

SPACE WEATHER
Current
Conditions

Solar Wind
speed: 379.7 km/s
density:
6.2 protons/cm3
explanation | more data
Updated: Today at 2245 UT

X-ray Solar Flares
6-hr max:
A0 2245 UT Apr19
24-hr: A0 2245 UT Apr19
explanation | more data
Updated: Today at 2245 UT

Daily Sun: 19 Apr '07

The sun is blank again--no sunspots. Credit: SOHO/MDI


Sunspot Number: 11
What is the sunspot number?
Updated: 18 Apr 2007

Far Side of the Sun

This holographic image reveals one possible sunspot on the far side of the sun. Image credit: SOHO/MDI

Interplanetary Mag. Field
Btotal: 1.9 nT
Bz:
0.4 nT south
explanation | more data
Updated: Today at 2246 UT

Coronal Holes:

A solar wind stream flowing from the indicated coronal hole should reach Earth on April 21st or 22nd. Credit: SOHO Extreme UV telescope


SPACE WEATHER
NOAA
Forecasts

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 2007 Apr 19 2203 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 2007 Apr 19 2203 UTC
Mid-latitudes
0-24 hr 24-48 hr
ACTIVE 30 % 25 %
MINOR 20 % 10 %
SEVERE 05 % 01 %

High latitudes
0-24 hr 24-48 hr
ACTIVE 35 % 30 %
MINOR 25 % 15 %
SEVERE 10 % 05 %

What's Up in Space -- 19 Apr 2007
Subscribe to Space Weather News

Did you miss last night's auroras? Next time get a wake-up call from Spaceweather PHONE.

BLANK SUN: Tiny sunspot 952 has dissolved, leaving the sun blank for the 13th day this month--and it's only April 19th. So many blank suns signals a deep nadir of the solar cycle.

MOON & VENUS: Don't wait until the sky fades to black. Go outside this evening while sunset is still in progress, and look west into the glow. Weather permitting, you'll see Venus and the crescent moon side by side: sky map.

Last night on the eve of the conjunction, P-M Hedén photographed the moon by itself over Vallentuna, Sweden:


Photo details: Canon Digital Rebel XT, 20mm Sigma lens, tripod

Tonight, just add Venus.

more images: from Denis Joye of Boulogne, France; from Oscar Blanco of La Coruna, Spain; from Jan Koeman of Kloetinge, The Netherlands; from Nicolai Wiegand of Schöningen, Germany; from Günther Strauch of Borken, Germany; from Samuel Hawkins of Hitchin, Hertfordshire, UK.

X IN THE SKY: If you live far from city lights, you may be able to see a faint but beautiful spectacle in the western sky tonight--a giant, glowing X. Physics professor Jimmy Westlake took this picture near Stagecoach, Colorado, on April 14th about an hour after sunset:


Photo details:
Fuji Finepix S2, 16mm Nikkor fisheye lens, ISO 800, 2 minutes

"It was spectacular," he says. "The bright, yellowish zodiacal light crossed the blue band of the Milky Way forming a large X in the sky. Venus and the Pleiades were completely immersed in zodiacal glow."

Zodiacal light--sunlight reflected from dust littering the plane of the solar system--is very faint. Even the slender crescent moon can interfere with it; so wait until the moon sets and allow your eyes time to fully adjust to the darkness. Or let your camera do the work: "I used a Fuji FinePix S2 digital camera set at ISO 800," says Westlake. "It was a 2-minute guided exposure with a 16-mm Nikkor fisheye lens at f2.8."



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 19 Apr 2007 there were 858 known Potentially
Hazardous Asteroids

April 2007 Earth-asteroid encounters
ASTEROID

 DATE
(UT)

MISS DISTANCE

MAG.

 SIZE
2006 VV2

Mar. 31

8.8 LD

10

2 km
2007 FY20

Apr. 2

5.3 LD

19

50 m
2007 DS84

Apr. 14

16 LD

15

325 m
2007 GU1

Apr. 16

2.1 LD

16

45 m
2007 HA

Apr. 17

6.5 LD

13

300 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.

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 -- from the National Solar Data Analysis Center

Recent Solar Events -- a summary of current solar conditions from lmsal.com.

What is the Magnetosphere?

The Lion Roars -- visit this site to find out what the magnetosphere sounds like.

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

Observable Comets -- from the Harvard Minor Planet Center.

Real-time Solar Wind Data -- from NASA's ACE spacecraft.

How powerful are solar wind gusts? Not very! 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 1996 to 2006

Mirages: Mirages in Finland; An Introduction to Mirages;

NOAA Solar Flare and Sunspot Data: 1994, 1995, 1996, 1997, 1998, 1999; 2000; 2001; 2002; 2003; 2004; 2005; Jan-Mar 2006; Apr-Jun 2006; Jul-Sep 2006; Oct-Dec 2006.

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


©2019 Spaceweather.com. All rights reserved.