~Space Weather Update~ A CME expected to reach Earth on April 4th is overdue. [1]

AURORA WATCH: A CME expected to reach Earth on April 4th is overdue. The cloud might have missed or maybe it's running late. Mindful of a possible impact, NOAA forecasters estimate a 15% chance of polar geomagnetic storms on April 5th. Aurora alerts: text [2], phone [3].

 

With the arrival of Spring, Arctic nights are growing shorter. "Soon, aurora season will be coming to an end," says Norwegian photographer Thorbjørn Riise Haagensen. "But it's not over yet." Last night Haagensen photographed this scene over Hillesøy, Norway:

 

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"Beginning in the middle of May, the midnight sun brings sunshine all night long," he says. "Already some daylight is visible at the horizon at midnight. There is still enough darkness, though, for the last dance of the auroras."

 

more images: from Bob Conzemius [5] of Grand Rapids, Minnesota; from Gilles Boutin [6] of Ivujivik Nunavik Canada; from Frank Olsen [7] of Blokken in Sortland, Norway; from Helge Mortensen [8] of Kvaløya, Norway; from Ole C. Salomonsen [9] of Sommarøy, Tromsø, Norway; from Thilo Bubek [10] of Tromsø, Norway;

HEAVENLY DEJA VU: At first glance, the picture below looks exactly like thousands of others taken this week as Venus passed [11] through the Pleaides star cluster. Look again. The date in the corner says "April 1972." Richard Keen of Boulder, Colorado, took the picture 40 years ago:

[12]

Talk about deja vu!

"Thanks to its orbit, Venus' appearance in the sky repeats itself almost exactly every 8 years," explains Keen. "Forty years ago, on April 2, 1972, Venus passed by the Pleiades only half a degree from its position two days ago. It's fun to compare this photo I took back in 1972 with this week's wonderful images."

Venus is exiting the Pleiades now, but as Keen's snapshot shows, there will be a next time--eight years from now to be exact. The next Venus-Pleaides conjunction is due in April 2020. Until then....

more images: from Fred Espenak [13] of Portal, Arizona; from Kamila Mazurkiewicz [14] of Puławy, Poland; from Jimmy Westlake [15] of Steamboat Springs, Colorado; from Efe Tuncel [16] of Ankara, Turkey; from Fritz Helmut Hemmerich [17] of Tenerife (Canary Islands); from Marion Haligowski [18] of Phoenix, Arizona; from Aaron Top [19] of Shallow Lake, Ontario; from Marek Nikodem [20] of Szubin, Poland; from M. Raşid Tuğral [21] of Ankara, Turkiye; from Ugur Ikizler [22] of Mudanya - Bursa / Turkey; from Gadi Eidelheit [23] of Givat Shmuel, Israel

Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/POES

Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 4 unsettled
explanation [33] | more data [34]

Interplanetary Mag. Field
B_total: 8.1 nT
B_z: 7.7 nT north
explanation [35] | more data [36]
Updated: Today at 1606 UT

Coronal Holes: 04 Apr 12

[37]

A solar wind stream flowing from this southern coronal hole could brush against Earth's magnetic field on April 7th. Credit: SDO/AIA.